Akiyama K

References (29)

Title : An ancestral function of strigolactones as symbiotic rhizosphere signals - Kodama_2022_Nat.Commun_13_3974
Author(s) : Kodama K , Rich MK , Yoda A , Shimazaki S , Xie X , Akiyama K , Mizuno Y , Komatsu A , Luo Y , Suzuki H , Kameoka H , Libourel C , Keller J , Sakakibara K , Nishiyama T , Nakagawa T , Mashiguchi K , Uchida K , Yoneyama K , Tanaka Y , Yamaguchi S , Shimamura M , Delaux PM , Nomura T , Kyozuka J
Ref : Nat Commun , 13 :3974 , 2022
Abstract : In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants. BSB synthesis is enhanced at AM symbiosis permissive conditions and BSB deficient mutants are impaired in AM symbiosis. In contrast, the absence of BSB synthesis has little effect on the growth and gene expression. We show that the introduction of the SL receptor of Arabidopsis renders M. paleacea cells BSB-responsive. These results suggest that BSB is not perceived by M. paleacea cells due to the lack of cognate SL receptors. We propose that SLs originated as AM symbiosis-inducing rhizosphere signaling molecules and were later recruited as plant hormone.
ESTHER : Kodama_2022_Nat.Commun_13_3974
PubMedSearch : Kodama_2022_Nat.Commun_13_3974
PubMedID: 35803942

Title : A carlactonoic acid methyltransferase that contributes to the inhibition of shoot branching in Arabidopsis - Mashiguchi_2022_Proc.Natl.Acad.Sci.U.S.A_119_e2111565119
Author(s) : Mashiguchi K , Seto Y , Onozuka Y , Suzuki S , Takemoto K , Wang Y , Dong L , Asami K , Noda R , Kisugi T , Kitaoka N , Akiyama K , Bouwmeester H , Yamaguchi S
Ref : Proc Natl Acad Sci U S A , 119 :e2111565119 , 2022
Abstract : SignificanceStrigolactones (SLs) are a group of apocarotenoid hormones, which regulates shoot branching and other diverse developmental processes in plants. The major bioactive form(s) of SLs as endogenous hormones has not yet been clarified. Here, we identify an Arabidopsis methyltransferase, CLAMT, responsible for the conversion of an inactive precursor to a biologically active SL that can interact with the SL receptor in vitro. Reverse genetic analysis showed that this enzyme plays an essential role in inhibiting shoot branching. This mutant also contributed to specifying the SL-related metabolites that could move from root to shoot in grafting experiments. Our work has identified a key enzyme necessary for the production of the bioactive form(s) of SLs.
ESTHER : Mashiguchi_2022_Proc.Natl.Acad.Sci.U.S.A_119_e2111565119
PubMedSearch : Mashiguchi_2022_Proc.Natl.Acad.Sci.U.S.A_119_e2111565119
PubMedID: 35344437

Title : Canonical strigolactones are not the major determinant of tillering but important rhizospheric signals in rice - Ito_2022_Sci.Adv_8_eadd1278
Author(s) : Ito S , Braguy J , Wang JY , Yoda A , Fiorilli V , Takahashi I , Jamil M , Felemban A , Miyazaki S , Mazzarella T , Chen GE , Shinozawa A , Balakrishna A , Berqdar L , Rajan C , Ali S , Haider I , Sasaki Y , Yajima S , Akiyama K , Lanfranco L , Zurbriggen MD , Nomura T , Asami T , Al-Babili S
Ref : Sci Adv , 8 :eadd1278 , 2022
Abstract : Strigolactones (SLs) are a plant hormone inhibiting shoot branching/tillering and a rhizospheric, chemical signal that triggers seed germination of the noxious root parasitic plant Striga and mediates symbiosis with beneficial arbuscular mycorrhizal fungi. Identifying specific roles of canonical and noncanonical SLs, the two SL subfamilies, is important for developing Striga-resistant cereals and for engineering plant architecture. Here, we report that rice mutants lacking canonical SLs do not show the shoot phenotypes known for SL-deficient plants, exhibiting only a delay in establishing arbuscular mycorrhizal symbiosis, but release exudates with a significantly decreased Striga seed-germinating activity. Blocking the biosynthesis of canonical SLs by TIS108, a specific enzyme inhibitor, significantly lowered Striga infestation without affecting rice growth. These results indicate that canonical SLs are not the determinant of shoot architecture and pave the way for increasing crop resistance by gene editing or chemical treatment.
ESTHER : Ito_2022_Sci.Adv_8_eadd1278
PubMedSearch : Ito_2022_Sci.Adv_8_eadd1278
PubMedID: 36322663

Title : Strigolactone biosynthesis catalyzed by cytochrome P450 and sulfotransferase in sorghum - Yoda_2021_New.Phytol_232_1999
Author(s) : Yoda A , Mori N , Akiyama K , Kikuchi M , Xie X , Miura K , Yoneyama K , Sato-Izawa K , Yamaguchi S , Nelson DC , Nomura T
Ref : New Phytol , 232 :1999 , 2021
Abstract : Root parasitic plants such as Striga, Orobanche, and Phelipanche spp. cause serious damage to crop production world-wide. Deletion of the Low Germination Stimulant 1 (LGS1) gene gives a Striga-resistance trait in sorghum (Sorghum bicolor). The LGS1 gene encodes a sulfotransferase-like protein, but its function has not been elucidated. Since the profile of strigolactones (SLs) that induce seed germination in root parasitic plants is altered in the lgs1 mutant, LGS1 is thought to be an SL biosynthetic enzyme. In order to clarify the enzymatic function of LGS1, we looked for candidate SL substrates that accumulate in the lgs1 mutants and performed in vivo and in vitro metabolism experiments. We found the SL precursor 18-hydroxycarlactonoic acid (18-OH-CLA) is a substrate for LGS1. CYP711A cytochrome P450 enzymes (SbMAX1 proteins) in sorghum produce 18-OH-CLA. When LGS1 and SbMAX1 coding sequences were co-expressed in Nicotiana benthamiana with the upstream SL biosynthesis genes from sorghum, the canonical SLs 5-deoxystrigol and 4-deoxyorobanchol were produced. This finding showed that LGS1 in sorghum uses a sulfo group to catalyze leaving of a hydroxyl group and cyclization of 18-OH-CLA. A similar SL biosynthetic pathway has not been found in other plant species.
ESTHER : Yoda_2021_New.Phytol_232_1999
PubMedSearch : Yoda_2021_New.Phytol_232_1999
PubMedID: 34525227

Title : Identification of two oxygenase genes involved in the respective biosynthetic pathways of canonical and non-canonical strigolactones in Lotus japonicus - Mori_2020_Planta_251_40
Author(s) : Mori N , Nomura T , Akiyama K
Ref : Planta , 251 :40 , 2020
Abstract : A cytochrome P450 and a 2-oxoglutarate-dependent dioxygenase genes responsible, respectively, for the biosyntheses of canonical and non-canonical strigolactones in Lotus japonicus were identified by transcriptome profiling and mutant screening. Strigolactones (SLs) are a group of apocarotenoids with diverse structures that act as phytohormones and rhizosphere signals. The model legume Lotus japonicus produces both canonical and non-canonical SLs, 5-deoxystrigol (5DS) and lotuslactone (LL), respectively, through oxidation of a common intermediate carlactone by the cytochrome P450 (CYP) enzyme MAX1. However, the pathways downstream of MAX1 and the branching point in the biosyntheses of 5DS and LL have not been elucidated. Here, we identified a CYP and a 2-oxoglutarate-dependent dioxygenase (2OGD) genes responsible, respectively, for the formation of Lotus SLs by transcriptome profiling using RNA-seq and screening of SL-deficient mutants from the Lotus retrotransposon 1 (LORE1) insertion mutant resource. The CYP and 2OGD genes were named DSD and LLD, respectively, after 5DS or LL defective phenotype of the mutants. The involvements of the genes in Lotus SL biosyntheses were confirmed by restoration of the mutant phenotype using Agrobacterium rhizogenes-mediated transformation to generate transgenic roots expressing the coding sequence. The transcript levels of DSD and LLD in roots as well as the levels of 5DS and LL in root exudates were reduced by phosphate fertilization and gibberellin treatment. This study can provide the opportunity to investigate how and why plants produce the two classes of SLs.
ESTHER : Mori_2020_Planta_251_40
PubMedSearch : Mori_2020_Planta_251_40
PubMedID: 31907631

Title : Hydroxyl carlactone derivatives are predominant strigolactones in Arabidopsis - Yoneyama_2020_Plant.Direct_4_e00219
Author(s) : Yoneyama K , Akiyama K , Brewer PB , Mori N , Kawano-Kawada M , Haruta S , Nishiwaki H , Yamauchi S , Xie X , Umehara M , Beveridge CA , Nomura T
Ref : Plant Direct , 4 :e00219 , 2020
Abstract : Strigolactones (SLs) regulate important aspects of plant growth and stress responses. Many diverse types of SL occur in plants, but a complete picture of biosynthesis remains unclear. In Arabidopsis thaliana, we have demonstrated that MAX1, a cytochrome P450 monooxygenase, converts carlactone (CL) into carlactonoic acid (CLA) and that LBO, a 2-oxoglutarate-dependent dioxygenase, can convert methyl carlactonoate (MeCLA) into a metabolite called [MeCLA + 16 Da]. In the present study, feeding experiments with deuterated MeCLAs revealed that [MeCLA + 16 Da] is hydroxymethyl carlactonoate (1'-HO-MeCLA). Importantly, this LBO metabolite was detected in plants. Interestingly, other related compounds, methyl 4-hydroxycarlactonoate (4-HO-MeCLA) and methyl 16-hydroxycarlactonoate (16-HO-MeCLA), were also found to accumulate in lbo mutants. 3-HO-, 4-HO-, and 16-HO-CL were detected in plants, but their expected corresponding metabolites, HO-CLAs, were absent in max1 mutants. These results suggest that HO-CL derivatives may be predominant SLs in Arabidopsis, produced through MAX1 and LBO.
ESTHER : Yoneyama_2020_Plant.Direct_4_e00219
PubMedSearch : Yoneyama_2020_Plant.Direct_4_e00219
PubMedID: 32399509

Title : Chemical identification of 18-hydroxycarlactonoic acid as an LjMAX1 product and in planta conversion of its methyl ester to canonical and non-canonical strigolactones in Lotus japonicus - Mori_2020_Phytochemistry_174_112349
Author(s) : Mori N , Sado A , Xie X , Yoneyama K , Asami K , Seto Y , Nomura T , Yamaguchi S , Akiyama K
Ref : Phytochemistry , 174 :112349 , 2020
Abstract : Strigolactones (SLs) are a group of plant apocarotenoids that act as rhizosphere signaling molecules for both arbuscular mycorrhizal fungi and root parasitic plants. They also regulate plant architecture as phytohormones. The model legume Lotus japonicus (synonym of Lotus corniculatus) produces canonical 5-deoxystrigol (5DS) and non-canonical lotuslactone (LL). The biosynthesis pathways of the two SLs remain elusive. In this study, we characterized the L. japonicus MAX1 homolog, LjMAX1, found in the Lotus japonicus genome assembly build 2.5. The L. japonicus max1 LORE1 insertion mutant was deficient in 5DS and LL production. A recombinant LjMAX1 protein expressed in yeast microsomes converted carlactone (CL) to 18-hydroxycarlactonoic acid (18-OH-CLA) via carlactonoic acid (CLA). Identity of 18-OH-CLA was confirmed by comparison of the methyl ester derivative of the MAX1 product with chemically synthesized methyl 18-hydroycarlactonoate (18-OH-MeCLA) using LC-MS/MS. (11R)-CL was detected as an endogenous compound in the root of L. japonicus.(13)C-labeled CL, CLA, and 18-OH-MeCLA were converted to [(13)C]-5DS and LL in plant feeding experiments using L. japonicus WT. These results showed that LjMAX1 is the crucial enzyme in the biosynthesis of Lotus SLs and that 18-hydroxylated carlactonoates are possible precursors for SL biosynthesis in L. japonicus.
ESTHER : Mori_2020_Phytochemistry_174_112349
PubMedSearch : Mori_2020_Phytochemistry_174_112349
PubMedID: 32213359

Title : Lotuslactone, a non-canonical strigolactone from Lotus japonicus - Xie_2019_Phytochemistry_157_200
Author(s) : Xie X , Mori N , Yoneyama K , Nomura T , Uchida K , Akiyama K
Ref : Phytochemistry , 157 :200 , 2019
Abstract : Root exudates from Lotus japonicus were found to contain at least three different hyphal branching-inducing compounds for the arbuscular mycorrhizal (AM) fungus Gigaspora margarita, one of which had been previously identified as (+)-5-deoxystrigol (5DS), a canonical strigolactone (SL). One of the two remaining unknown hyphal branching inducers was purified and named lotuslactone. Its structure was determined as methyl (E)-2-(3-acetoxy-2-hydroxy-7-methyl-1-oxo-1,2,3,4,5,6-hexahydroazulen-2-yl)-3-(((R)-4-methyl-5-oxo-2,5-dihydrofuran-2-yl)oxy)acrylate, by 1D and 2D NMR spectroscopy, and HR-ESI- and EI-MS. Although lotuslactone, a non-canonical SL, contains the AB-ring and the enol ether-bridged D-ring, it lacks the C-ring and has a seven-membered cycloheptadiene in the A-ring part as in medicaol, a major SL of Medicago truncatula. Lotuslactone was much less active than 5DS, but showed comparable activity to methyl carlactonoate (MeCLA) in inducing hyphal branching of G. margarita. Other natural non-canonical SLs including avenaol, heliolactone, and zealactone (methyl zealactonoate) were also found to be moderate to weak inducers of hyphal branching in the AM fungus. Lotuslactone strongly elicited seed germination in Phelipanche ramosa and Orobanche minor, but Striga hermonthica seeds were 100-fold less sensitive to this stimulant.
ESTHER : Xie_2019_Phytochemistry_157_200
PubMedSearch : Xie_2019_Phytochemistry_157_200
PubMedID: 30439621

Title : Regulation of biosynthesis, perception, and functions of strigolactones for promoting arbuscular mycorrhizal symbiosis and managing root parasitic weeds - Yoneyama_2019_Pest.Manag.Sci_75_2353
Author(s) : Yoneyama K , Xie X , Nomura T , Takahashi I , Asami T , Mori N , Akiyama K , Kusajima M , Nakashita H
Ref : Pest Manag Sci , 75 :2353 , 2019
Abstract : Strigolactones (SLs) are carotenoid-derived plant secondary metabolites that play important roles in various aspects of plant growth and development as plant hormones, and in rhizosphere communications with symbiotic microbes and also root parasitic weeds. Therefore, sophisticated regulation of the biosynthesis, perception and functions of SLs is expected to promote symbiosis of beneficial microbes including arbuscular mycorrhizal (AM) fungi and also to retard parasitism by devastating root parasitic weeds. We have developed SL mimics with different skeletons, SL biosynthesis inhibitors acting at different biosynthetic steps, SL perception inhibitors that covalently bind to the SL receptor D14, and SL function inhibitors that bind to the serine residue at the catalytic site. In greenhouse pot tests, TIS108, an azole-type SL biosynthesis inhibitor effectively reduced numbers of attached root parasites Orobanche minor and Striga hermonthica without affecting their host plants; tomato and rice, respectively. AM colonization resulted in weak but distinctly enhanced plant resistance to pathogens. SL mimics can be used to promote AM symbiosis and to reduce the application rate of systemic-acquired resistance inducers which are generally phytotoxic to horticultural crops. (c) 2019 Society of Chemical Industry.
ESTHER : Yoneyama_2019_Pest.Manag.Sci_75_2353
PubMedSearch : Yoneyama_2019_Pest.Manag.Sci_75_2353
PubMedID: 30843315

Title : Strigolactone perception and deactivation by a hydrolase receptor DWARF14 - Seto_2019_Nat.Commun_10_191
Author(s) : Seto Y , Yasui R , Kameoka H , Tamiru M , Cao M , Terauchi R , Sakurada A , Hirano R , Kisugi T , Hanada A , Umehara M , Seo E , Akiyama K , Burke J , Takeda-Kamiya N , Li W , Hirano Y , Hakoshima T , Mashiguchi K , Noel JP , Kyozuka J , Yamaguchi S
Ref : Nat Commun , 10 :191 , 2019
Abstract : The perception mechanism for the strigolactone (SL) class of plant hormones has been a subject of debate because their receptor, DWARF14 (D14), is an alpha/beta-hydrolase that can cleave SLs. Here we show via time-course analyses of SL binding and hydrolysis by Arabidopsis thaliana D14, that the level of uncleaved SL strongly correlates with the induction of the active signaling state. In addition, we show that an AtD14(D218A) catalytic mutant that lacks enzymatic activity is still able to complement the atd14 mutant phenotype in an SL-dependent manner. We conclude that the intact SL molecules trigger the D14 active signaling state, and we also describe that D14 deactivates bioactive SLs by the hydrolytic degradation after signal transmission. Together, these results reveal that D14 is a dual-functional receptor, responsible for both the perception and deactivation of bioactive SLs.
ESTHER : Seto_2019_Nat.Commun_10_191
PubMedSearch : Seto_2019_Nat.Commun_10_191
PubMedID: 30643123
Gene_locus related to this paper: arath-AtD14

Title : Low Infection of Phelipanche aegyptiaca in Micro-Tom Mutants Deficient in CAROTENOIDCLEAVAGE DIOXYGENASE 8 - Hasegawa_2018_Int.J.Mol.Sci_19_
Author(s) : Hasegawa S , Tsutsumi T , Fukushima S , Okabe Y , Saito J , Katayama M , Shindo M , Yamada Y , Shimomura K , Yoneyama K , Akiyama K , Aoki K , Ariizumi T , Ezura H , Yamaguchi S , Umehara M
Ref : Int J Mol Sci , 19 : , 2018
Abstract : Strigolactones (SLs), a group of plant hormones, induce germination of root-parasitic plants and inhibit shoot branching in many plants. Shoot branching is an important trait that affects the number and quality of flowers and fruits. Root-parasitic plants, such as Phelipanche spp., infect tomato roots and cause economic damage in Europe and North Africa-hence why resistant tomato cultivars are needed. In this study, we found carotenoid cleavage dioxygenase 8-defective mutants of Micro-Tom tomato (slccd8) by the "targeting induced local lesions in genomes" (TILLING) method. The mutants showed excess branching, which was suppressed by exogenously applied SL. Grafting shoot scions of the slccd8 mutants onto wild-type (WT) rootstocks restored normal branching in the scions. The levels of endogenous orobanchol and solanacol in WT were enough detectable, whereas that in the slccd8 mutants were below the detection limit of quantification analysis. Accordingly, root exudates of the slccd8 mutants hardly stimulated seed germination of root parasitic plants. In addition, SL deficiency did not critically affect the fruit traits of Micro-Tom. Using a rhizotron system, we also found that Phelipanche aegyptiaca infection was lower in the slccd8 mutants than in wild-type Micro-Tom because of the low germination. We propose that the slccd8 mutants might be useful as new tomato lines resistant to P. aegyptiaca.
ESTHER : Hasegawa_2018_Int.J.Mol.Sci_19_
PubMedSearch : Hasegawa_2018_Int.J.Mol.Sci_19_
PubMedID: 30200620

Title : Conversion of carlactone to carlactonoic acid is a conserved function of MAX1 homologs in strigolactone biosynthesis - Yoneyama_2018_New.Phytol_218_1522
Author(s) : Yoneyama K , Mori N , Sato T , Yoda A , Xie X , Okamoto M , Iwanaga M , Ohnishi T , Nishiwaki H , Asami T , Yokota T , Akiyama K , Nomura T
Ref : New Phytol , 218 :1522 , 2018
Abstract : Strigolactones (SLs) are a class of plant hormones which regulate shoot branching and function as host recognition signals for symbionts and parasites in the rhizosphere. However, steps in SL biosynthesis after carlactone (CL) formation remain elusive. This study elucidated the common and diverse functions of MAX1 homologs which catalyze CL oxidation. We have reported previously that ArabidopsisMAX1 converts CL to carlactonoic acid (CLA), whereas a rice MAX1 homolog has been shown to catalyze the conversion of CL to 4-deoxyorobanchol (4DO). To determine which reaction is conserved in the plant kingdom, we investigated the enzymatic function of MAX1 homologs in Arabidopsis, rice, maize, tomato, poplar and Selaginella moellendorffii. The conversion of CL to CLA was found to be a common reaction catalyzed by MAX1 homologs, and MAX1s can be classified into three types: A1-type, converting CL to CLA; A2-type, converting CL to 4DO via CLA; and A3-type, converting CL to CLA and 4DO to orobanchol. CLA was detected in root exudates from poplar and Selaginella, but not ubiquitously in other plants examined in this study, suggesting its role as a species-specific signal in the rhizosphere. This study provides new insights into the roles of MAX1 in endogenous and rhizosphere signaling.
ESTHER : Yoneyama_2018_New.Phytol_218_1522
PubMedSearch : Yoneyama_2018_New.Phytol_218_1522
PubMedID: 29479714

Title : Which are the major players, canonical or non-canonical strigolactones? - Yoneyama_2018_J.Exp.Bot_69_2231
Author(s) : Yoneyama K , Xie X , Kisugi T , Nomura T , Nakatani Y , Akiyama K , McErlean CSP
Ref : J Exp Bot , 69 :2231 , 2018
Abstract : Strigolactones (SLs) can be classified into two structurally distinct groups: canonical and non-canonical SLs. Canonical SLs contain the ABCD ring system, and non-canonical SLs lack the A, B, or C ring but have the enol ether-D ring moiety, which is essential for biological activities. The simplest non-canonical SL is the SL biosynthetic intermediate carlactone. In plants, carlactone and its oxidized metabolites, such as carlactonoic acid and methyl carlactonoate, are present in root and shoot tissues. In some plant species, including black oat (Avena strigosa), sunflower (Helianthus annuus), and maize (Zea mays), non-canonical SLs in the root exudates are major germination stimulants. Various plant species, such as tomato (Solanum lycopersicum), Arabidopsis, and poplar (Populus spp.), release carlactonoic acid into the rhizosphere. These observations suggest that both canonical and non-canonical SLs act as host-recognition signals in the rhizosphere. In contrast, the limited distribution of canonical SLs in the plant kingdom, and the structure-specific and stereospecific transportation of canonical SLs from roots to shoots, suggest that plant hormones inhibiting shoot branching are not canonical SLs but, rather, are non-canonical SLs.
ESTHER : Yoneyama_2018_J.Exp.Bot_69_2231
PubMedSearch : Yoneyama_2018_J.Exp.Bot_69_2231
PubMedID: 29522151

Title : A femtomolar-range suicide germination stimulant for the parasitic plant Striga hermonthica - Uraguchi_2018_Science_362_1301
Author(s) : Uraguchi D , Kuwata K , Hijikata Y , Yamaguchi R , Imaizumi H , Am S , Rakers C , Mori N , Akiyama K , Irle S , McCourt P , Kinoshita T , Ooi T , Tsuchiya Y
Ref : Science , 362 :1301 , 2018
Abstract : The parasitic plant Striga hermonthica has been causing devastating damage to the crop production in Africa. Because Striga requires host-generated strigolactones to germinate, the identification of selective and potent strigolactone agonists could help control these noxious weeds. We developed a selective agonist, sphynolactone-7, a hybrid molecule originated from chemical screening, that contains two functional modules derived from a synthetic scaffold and a core component of strigolactones. Cooperative action of these modules in the activation of a high-affinity strigolactone receptor ShHTL7 allows sphynolactone-7 to provoke Striga germination with potency in the femtomolar range. We demonstrate that sphynolactone-7 is effective for reducing Striga parasitism without impinging on host strigolactone-related processes.
ESTHER : Uraguchi_2018_Science_362_1301
PubMedSearch : Uraguchi_2018_Science_362_1301
PubMedID: 30545887

Title : Carlactone-type strigolactones and their synthetic analogues as inducers of hyphal branching in arbuscular mycorrhizal fungi - Mori_2016_Phytochemistry_130_90
Author(s) : Mori N , Nishiuma K , Sugiyama T , Hayashi H , Akiyama K
Ref : Phytochemistry , 130 :90 , 2016
Abstract : Hyphal branching in the vicinity of host roots is a host recognition response of arbuscular mycorrhizal fungi. This morphological event is elicited by strigolactones. Strigolactones are carotenoid-derived terpenoids that are synthesized from carlactone and its oxidized derivatives. To test the possibility that carlactone and its oxidized derivatives might act as host-derived precolonization signals in arbuscular mycorrhizal symbiosis, carlactone, carlactonoic acid, and methyl carlactonoate as well as monohydroxycarlactones, 4-, 18-, and 19-hydroxycarlactones, were synthesized chemically and evaluated for hyphal branching-inducing activity in germinating spores of the arbuscular mycorrhizal fungus Gigaspora margarita. Hyphal branching activity was found to correlate with the degree of oxidation at C-19 methyl. Carlactone was only weakly active (100 ng/disc), whereas carlactonoic acid showed comparable activity to the natural canonical strigolactones such as strigol and sorgomol (100 pg/disc). Hydroxylation at either C-4 or C-18 did not significantly affect the activity. A series of carlactone analogues, named AD ester and AA'D diester, was synthesized by reacting formyl Meldrum's acid with benzyl, cyclohexylmethyl, and cyclogeranyl alcohols (the A-ring part), followed by coupling of the potassium enolates of the resulting formylacetic esters with the D-ring butenolide. AD ester analogues exhibited moderate activity (1 ng-100 pg/disc), while AA'D diester analogues having cyclohexylmethyl and cyclogeranyl groups were highly active on the AM fungus (10 pg/disc). These results indicate that the oxidation of methyl to carboxyl at C-19 in carlactone is a prerequisite but BC-ring formation is not essential to show hyphal branching activity comparable to that of canonical strigolactones.
ESTHER : Mori_2016_Phytochemistry_130_90
PubMedSearch : Mori_2016_Phytochemistry_130_90
PubMedID: 27264641

Title : LATERAL BRANCHING OXIDOREDUCTASE acts in the final stages of strigolactone biosynthesis in Arabidopsis - Brewer_2016_Proc.Natl.Acad.Sci.U.S.A_113_6301
Author(s) : Brewer PB , Yoneyama K , Filardo F , Meyers E , Scaffidi A , Frickey T , Akiyama K , Seto Y , Dun EA , Cremer JE , Kerr SC , Waters MT , Flematti GR , Mason MG , Weiller G , Yamaguchi S , Nomura T , Smith SM , Beveridge CA
Ref : Proc Natl Acad Sci U S A , 113 :6301 , 2016
Abstract : Strigolactones are a group of plant compounds of diverse but related chemical structures. They have similar bioactivity across a broad range of plant species, act to optimize plant growth and development, and promote soil microbe interactions. Carlactone, a common precursor to strigolactones, is produced by conserved enzymes found in a number of diverse species. Versions of the MORE AXILLARY GROWTH1 (MAX1) cytochrome P450 from rice and Arabidopsis thaliana make specific subsets of strigolactones from carlactone. However, the diversity of natural strigolactones suggests that additional enzymes are involved and remain to be discovered. Here, we use an innovative method that has revealed a missing enzyme involved in strigolactone metabolism. By using a transcriptomics approach involving a range of treatments that modify strigolactone biosynthesis gene expression coupled with reverse genetics, we identified LATERAL BRANCHING OXIDOREDUCTASE (LBO), a gene encoding an oxidoreductase-like enzyme of the 2-oxoglutarate and Fe(II)-dependent dioxygenase superfamily. Arabidopsis lbo mutants exhibited increased shoot branching, but the lbo mutation did not enhance the max mutant phenotype. Grafting indicated that LBO is required for a graft-transmissible signal that, in turn, requires a product of MAX1. Mutant lbo backgrounds showed reduced responses to carlactone, the substrate of MAX1, and methyl carlactonoate (MeCLA), a product downstream of MAX1. Furthermore, lbo mutants contained increased amounts of these compounds, and the LBO protein specifically converts MeCLA to an unidentified strigolactone-like compound. Thus, LBO function may be important in the later steps of strigolactone biosynthesis to inhibit shoot branching in Arabidopsis and other seed plants.
ESTHER : Brewer_2016_Proc.Natl.Acad.Sci.U.S.A_113_6301
PubMedSearch : Brewer_2016_Proc.Natl.Acad.Sci.U.S.A_113_6301
PubMedID: 27194725

Title : Medicaol, a strigolactone identified as a putative didehydro-orobanchol isomer, from Medicago truncatula - Tokunaga_2015_Phytochemistry_111_91
Author(s) : Tokunaga T , Hayashi H , Akiyama K
Ref : Phytochemistry , 111 :91 , 2015
Abstract : A major strigolactone produced by the model legume Medicago truncatula (barrel medic) has been tentatively identified as a didehydro-orobanchol isomer. In this study, a putative didehydro-orobanchol isomer was isolated from root exudates collected from barrel medic grown hydroponically under phosphate-starved conditions. The structure and absolute configurations of this strigolactone, named medicaol, were determined by a combination of spectroscopic analysis and spectral comparison with 4-deoxymedicaol which was synthesized using solvolysis and rearrangement of hydroxymethylhexahydroindenone to tetrahydroazulenone as a key step. Medicaol has a seven-membered cycloheptadiene in the A ring instead of a typical six-membered cyclohexene. Medicaol and 4-deoxymedicaol showed activity comparable to their corresponding six-membered A ring relatives, orobanchol and 4-deoxyorobanchol (ent-2'-epi-5-deoxystrigol), in inducing hyphal branching of germinating spores of an arbuscular mycorrhizal fungus Gigaspora margarita. Plausible biosynthetic pathways from 4-deoxyorobanchol to medicaol are also proposed.
ESTHER : Tokunaga_2015_Phytochemistry_111_91
PubMedSearch : Tokunaga_2015_Phytochemistry_111_91
PubMedID: 25593009

Title : Carlactone is an endogenous biosynthetic precursor for strigolactones - Seto_2014_Proc.Natl.Acad.Sci.U.S.A_111_1640
Author(s) : Seto Y , Sado A , Asami K , Hanada A , Umehara M , Akiyama K , Yamaguchi S
Ref : Proc Natl Acad Sci U S A , 111 :1640 , 2014
Abstract : Strigolactones (SLs) are a class of terpenoid plant hormones that regulate shoot branching as well as being known as root-derived signals for symbiosis and parasitism. SL has tricyclic-lactone (ABC-ring) and methyl butenolide (D-ring), and they are connected through an enol ether bridge. Recently, a putative biosynthetic intermediate called carlactone (CL), of which carbon skeleton is in part similar to those of SLs, was identified by biochemical analysis of three biosynthetic enzymes, DWARF27, CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7), and CCD8 in vitro. However, CL has never been identified from plant tissues, and the conversion of CL to SLs has not been proven in vivo. To address these questions, we chemically synthesized (13)C-labeled CL. We show that (13)C-labeled CL is converted to (-)-[(13)C]-2'-epi-5-deoxystrigol ((-)-2'-epi-5DS) and [(13)C]-orobanchol, endogenous SLs in rice, in the dwarf10 mutant, which is defective in CCD8. In addition, we successfully identified endogenous CL by using liquid chromatography-quadrupole/time-of-flight tandem mass spectrometry in rice and Arabidopsis. Furthermore, we determined the absolute stereochemistry of endogenous CL to be (11R)-configuration, which is the same as that of (-)-2'-epi-5DS at the corresponding position. Feeding experiments showed that only the (11R)-isomer of CL, but not the (11S)-isomer, was converted to (-)-2'-epi-5DS in vivo. Taken together, our data provide conclusive evidence that CL is an endogenous SL precursor that is stereospecifically recognized in the biosynthesis pathway.
ESTHER : Seto_2014_Proc.Natl.Acad.Sci.U.S.A_111_1640
PubMedSearch : Seto_2014_Proc.Natl.Acad.Sci.U.S.A_111_1640
PubMedID: 24434551

Title : Carlactone is converted to carlactonoic acid by MAX1 in Arabidopsis and its methyl ester can directly interact with AtD14 in vitro - Abe_2014_Proc.Natl.Acad.Sci.U.S.A_111_18084
Author(s) : Abe S , Sado A , Tanaka K , Kisugi T , Asami K , Ota S , Kim HI , Yoneyama K , Xie X , Ohnishi T , Seto Y , Yamaguchi S , Akiyama K , Nomura T
Ref : Proc Natl Acad Sci U S A , 111 :18084 , 2014
Abstract : Strigolactones (SLs) stimulate seed germination of root parasitic plants and induce hyphal branching of arbuscular mycorrhizal fungi in the rhizosphere. In addition, they have been classified as a new group of plant hormones essential for shoot branching inhibition. It has been demonstrated thus far that SLs are derived from carotenoid via a biosynthetic precursor carlactone (CL), which is produced by sequential reactions of DWARF27 (D27) enzyme and two carotenoid cleavage dioxygenases CCD7 and CCD8. We previously found an extreme accumulation of CL in the more axillary growth1 (max1) mutant of Arabidopsis, which exhibits increased lateral inflorescences due to SL deficiency, indicating that CL is a probable substrate for MAX1 (CYP711A1), a cytochrome P450 monooxygenase. To elucidate the enzymatic function of MAX1 in SL biosynthesis, we incubated CL with a recombinant MAX1 protein expressed in yeast microsomes. MAX1 catalyzed consecutive oxidations at C-19 of CL to convert the C-19 methyl group into carboxylic acid, 9-desmethyl-9-carboxy-CL [designated as carlactonoic acid (CLA)]. We also identified endogenous CLA and its methyl ester [methyl carlactonoate (MeCLA)] in Arabidopsis plants using LC-MS/MS. Although an exogenous application of either CLA or MeCLA suppressed the growth of lateral inflorescences of the max1 mutant, MeCLA, but not CLA, interacted with Arabidopsis thaliana DWARF14 (AtD14) protein, a putative SL receptor, as shown by differential scanning fluorimetry and hydrolysis activity tests. These results indicate that not only known SLs but also MeCLA are biologically active in inhibiting shoot branching in Arabidopsis.
ESTHER : Abe_2014_Proc.Natl.Acad.Sci.U.S.A_111_18084
PubMedSearch : Abe_2014_Proc.Natl.Acad.Sci.U.S.A_111_18084
PubMedID: 25425668
Gene_locus related to this paper: arath-AtD14

Title : Confirming stereochemical structures of strigolactones produced by rice and tobacco - Xie_2013_Mol.Plant_6_153
Author(s) : Xie X , Yoneyama K , Kisugi T , Uchida K , Ito S , Akiyama K , Hayashi H , Yokota T , Nomura T
Ref : Mol Plant , 6 :153 , 2013
Abstract : Major strigolactones (SLs) produced by rice (Oryza sativa L. cv. Nipponbare) and tobacco (Nicotiana tabacum L. cv. Michinoku No. 1) were purified and their stereochemical structures were determined by comparing with optically pure synthetic standards for their NMR and CD data and retention times and mass fragmentations in ESI-LC/MS and GC-MS. SLs purified from root exudates of rice plants were orobanchol, orobanchyl acetate, and ent-2'-epi-5-deoxystrigol. In addition to these SLs, 7-oxoorobanchyl acetate and the putative three methoxy-5-deoxystrigol isomers were detected by LC-MS/MS. The production of 7-oxoorobanchyl acetate seemed to occur in the early growth stage, as it was detected only in the root exudates collected during the first week of incubation. The root exudates of tobacco contained at least 11 SLs, including solanacol, solanacyl acetate, orobanchol, ent-2'-epi-orobanchol, orobanchyl acetate, ent-2'-epi-orobanchyl acetate, 5-deoxystrigol, ent-2'-epi-5-deoxystrigol, and three isomers of putative didehydro-orobanchol whose structures remain to be clarified. Furthermore, two sorgolactone isomers but not sorgolactone were detected as minor SLs by LC-MS/MS analysis. It is intriguing to note that rice plants produced only orobanchol-type SLs, derived from ent-2'-epi-5-deoxystrigol, but both orobanchol-type and strigol-type SLs, derived from 5-deoxystrigol were detected in tobacco plants.
ESTHER : Xie_2013_Mol.Plant_6_153
PubMedSearch : Xie_2013_Mol.Plant_6_153
PubMedID: 23204500

Title : Lupin pyranoisoflavones inhibiting hyphal development in arbuscular mycorrhizal fungi - Akiyama_2010_Phytochemistry_71_1865
Author(s) : Akiyama K , Tanigawa F , Kashihara T , Hayashi H
Ref : Phytochemistry , 71 :1865 , 2010
Abstract : White lupin (Lupinus albus L.), a non-host plant for arbuscular mycorrhizal (AM) fungi in the typically mycotrophic family Fabaceae, has been investigated for root metabolites that inhibit hyphal development in AM fungi. Four known pyranoisoflavones, licoisoflavone B (1), sophoraisoflavone A (2), alpinumisoflavone (3) and 3'-hydroxy-4'-O-methylalpinumisoflavone (4), together with three previously unknown pyranoisoflavones, lupindipyranoisoflavone A (5), 10'-hydroxylicoisoflavone B (6) and 10'-hydroxysophoraisoflavone A (7) were isolated from the root exudates of white lupin as an inhibitor of germ tube growth in the AM fungus Gigaspora margarita. Pyranoisoflavones 1, 2 and 3 strongly inhibited germ tube growth at 0.63, 1.25 and 0.63 microg/disc, respectively. The remaining compounds 4-7 were either moderate or weak inhibitors that inhibited germ tube growth at concentrations higher than 10 microg/disc. Licoisoflavone B (1) and sophoraisoflavone A (2) completely inhibited hyphal branching induced by a lupin strigolactone, orobanchyl acetate, in G. margarita at 0.16 and 0.63 microg/disc, respectively.
ESTHER : Akiyama_2010_Phytochemistry_71_1865
PubMedSearch : Akiyama_2010_Phytochemistry_71_1865
PubMedID: 20813384

Title : Strigolactones, host recognition signals for root parasitic plants and arbuscular mycorrhizal fungi, from Fabaceae plants - Yoneyama_2008_New.Phytol_179_484
Author(s) : Yoneyama K , Xie X , Sekimoto H , Takeuchi Y , Ogasawara S , Akiyama K , Hayashi H
Ref : New Phytol , 179 :484 , 2008
Abstract : Both root parasitic plants and arbuscular mycorrhizal (AM) fungi take advantage of strigolactones, released from plant roots as signal molecules in the initial communication with host plants, in order to commence parasitism and mutualism, respectively. In this study, strigolactones in root exudates from 12 Fabaceae plants, including hydroponically grown white lupin (Lupinus albus), a nonhost of AM fungi, were characterized by comparing retention times of germination stimulants on reverse-phase high-performance liquid chromatography (HPLC) with those of standards and by using tandem mass spectrometry (LC/MS/MS). All the plant species examined were found to exude known strigolactones, such as orobanchol, orobanchyl acetate, and 5-deoxystrigol, suggesting that these strigolactones are widely distributed in the Fabaceae. It should be noted that even the nonmycotrophic L. albus exuded orobanchol, orobanchyl acetate, 5-deoxystrigol, and novel germination stimulants. By contrast to the mycotrophic Fabaceae plant Trifolium pratense, in which phosphorus deficiency promoted strigolactone exudation, neither phosphorus nor nitrogen deficiency increased exudation of these strigolactones in L. albus. Therefore, the regulation of strigolactone production and/or exudation seems to be closely related to the nutrient acquisition strategy of the plants.
ESTHER : Yoneyama_2008_New.Phytol_179_484
PubMedSearch : Yoneyama_2008_New.Phytol_179_484
PubMedID: 19086293

Title : Inhibition of shoot branching by new terpenoid plant hormones - Umehara_2008_Nature_455_195
Author(s) : Umehara M , Hanada A , Yoshida S , Akiyama K , Arite T , Takeda-Kamiya N , Magome H , Kamiya Y , Shirasu K , Yoneyama K , Kyozuka J , Yamaguchi S
Ref : Nature , 455 :195 , 2008
Abstract : Shoot branching is a major determinant of plant architecture and is highly regulated by endogenous and environmental cues. Two classes of hormones, auxin and cytokinin, have long been known to have an important involvement in controlling shoot branching. Previous studies using a series of mutants with enhanced shoot branching suggested the existence of a third class of hormone(s) that is derived from carotenoids, but its chemical identity has been unknown. Here we show that levels of strigolactones, a group of terpenoid lactones, are significantly reduced in some of the branching mutants. Furthermore, application of strigolactones inhibits shoot branching in these mutants. Strigolactones were previously found in root exudates acting as communication chemicals with parasitic weeds and symbiotic arbuscular mycorrhizal fungi. Thus, we propose that strigolactones act as a new hormone class or their biosynthetic precursors in regulating above-ground plant architecture, and also have a function in underground communication with other neighbouring organisms.
ESTHER : Umehara_2008_Nature_455_195
PubMedSearch : Umehara_2008_Nature_455_195
PubMedID: 18690207

Title : Strigolactones: chemical signals for fungal symbionts and parasitic weeds in plant roots - Akiyama_2006_Ann.Bot_97_925
Author(s) : Akiyama K , Hayashi H
Ref : Ann Bot , 97 :925 , 2006
Abstract : AIMS: Arbuscular mycorrhizae are formed between >80 % of land plants and arbuscular mycorrhizal (AM) fungi. This Botanical Briefing highlights the chemical identification of strigolactones as a host-recognition signal for AM fungi, and their role in the establishment of arbuscular mycorrhizae as well as in the seed germination of parasitic weeds. SCOPE: Hyphal branching has long been described as the first morphological event in host recognition by AM fungi during the pre-infection stages. Host roots release signalling molecules called 'branching factors' that induce extensive hyphal branching in AM fungi. Strigolactones exuded from host roots have recently been identified as an inducer of hyphal branching in AM fungi. Strigolactones are a group of sesquiterpenes, previously isolated as seed germination stimulants for the parasitic weeds Striga and Orobanche. Parasitic weeds might find their potential hosts by detecting strigolactones, which are released from plant roots upon phosphate deficiency in communication with AM fungi. In addition to acting as a signalling molecule, strigolactones might stimulate the production of fungal symbiotic signals called 'Myc factors' in AM fungi. CONCLUSIONS: Isolation and identification of plant symbiotic signals open up new ways for studying the molecular basis of plant-AM-fungus interactions. This discovery provides a clear answer to a long-standing question in parasitic plant biology: what is the natural role for germination stimulants? It could also provide a new strategy for the management and control of beneficial fungal symbionts and of devastating parasitic weeds in agriculture and natural ecosystems.
ESTHER : Akiyama_2006_Ann.Bot_97_925
PubMedSearch : Akiyama_2006_Ann.Bot_97_925
PubMedID: 16574693

Title : Plant sesquiterpenes induce hyphal branching in arbuscular mycorrhizal fungi - Akiyama_2005_Nature_435_824
Author(s) : Akiyama K , Matsuzaki K , Hayashi H
Ref : Nature , 435 :824 , 2005
Abstract : Arbuscular mycorrhizal (AM) fungi form mutualistic, symbiotic associations with the roots of more than 80% of land plants. The fungi are incapable of completing their life cycle in the absence of a host root. Their spores can germinate and grow in the absence of a host, but their hyphal growth is very limited. Little is known about the molecular mechanisms that govern signalling and recognition between AM fungi and their host plants. In one of the first stages of host recognition, the hyphae of AM fungi show extensive branching in the vicinity of host roots before formation of the appressorium, the structure used to penetrate the plant root. Host roots are known to release signalling molecules that trigger hyphal branching, but these branching factors have not been isolated. Here we have isolated a branching factor from the root exudates of Lotus japonicus and used spectroscopic analysis and chemical synthesis to identify it as a strigolactone, 5-deoxy-strigol. Strigolactones are a group of sesquiterpene lactones, previously isolated as seed-germination stimulants for the parasitic weeds Striga and Orobanche. The natural strigolactones 5-deoxy-strigol, sorgolactone and strigol, and a synthetic analogue, GR24, induced extensive hyphal branching in germinating spores of the AM fungus Gigaspora margarita at very low concentrations.
ESTHER : Akiyama_2005_Nature_435_824
PubMedSearch : Akiyama_2005_Nature_435_824
PubMedID: 15944706

Title : Empirical analysis of transcriptional activity in the Arabidopsis genome - Yamada_2003_Science_302_842
Author(s) : Yamada K , Lim J , Dale JM , Chen H , Shinn P , Palm CJ , Southwick AM , Wu HC , Kim C , Nguyen M , Pham P , Cheuk R , Karlin-Newmann G , Liu SX , Lam B , Sakano H , Wu T , Yu G , Miranda M , Quach HL , Tripp M , Chang CH , Lee JM , Toriumi M , Chan MM , Tang CC , Onodera CS , Deng JM , Akiyama K , Ansari Y , Arakawa T , Banh J , Banno F , Bowser L , Brooks S , Carninci P , Chao Q , Choy N , Enju A , Goldsmith AD , Gurjal M , Hansen NF , Hayashizaki Y , Johnson-Hopson C , Hsuan VW , Iida K , Karnes M , Khan S , Koesema E , Ishida J , Jiang PX , Jones T , Kawai J , Kamiya A , Meyers C , Nakajima M , Narusaka M , Seki M , Sakurai T , Satou M , Tamse R , Vaysberg M , Wallender EK , Wong C , Yamamura Y , Yuan S , Shinozaki K , Davis RW , Theologis A , Ecker JR
Ref : Science , 302 :842 , 2003
Abstract : Functional analysis of a genome requires accurate gene structure information and a complete gene inventory. A dual experimental strategy was used to verify and correct the initial genome sequence annotation of the reference plant Arabidopsis. Sequencing full-length cDNAs and hybridizations using RNA populations from various tissues to a set of high-density oligonucleotide arrays spanning the entire genome allowed the accurate annotation of thousands of gene structures. We identified 5817 novel transcription units, including a substantial amount of antisense gene transcription, and 40 genes within the genetically defined centromeres. This approach resulted in completion of approximately 30% of the Arabidopsis ORFeome as a resource for global functional experimentation of the plant proteome.
ESTHER : Yamada_2003_Science_302_842
PubMedSearch : Yamada_2003_Science_302_842
PubMedID: 14593172
Gene_locus related to this paper: arath-AT2G42690 , arath-AT4g30610 , arath-At5g13640 , arath-AT5G20520 , arath-AT5G27320 , arath-CGEP , arath-clh1 , arath-clh2 , arath-CXE12 , arath-CXE15 , arath-SCP25 , arath-F14F8.240 , arath-MES6 , arath-LCAT1 , arath-PLA11 , arath-PLA15 , arath-PLA16 , arath-PLA17 , arath-SCP8 , arath-SCP11 , arath-SCP40 , arath-MES14 , arath-AXR4 , arath-SFGH , arath-B9DFR3 , arath-pae2

Title : Functional annotation of a full-length Arabidopsis cDNA collection - Seki_2002_Science_296_141
Author(s) : Seki M , Narusaka M , Kamiya A , Ishida J , Satou M , Sakurai T , Nakajima M , Enju A , Akiyama K , Oono Y , Muramatsu M , Hayashizaki Y , Kawai J , Carninci P , Itoh M , Ishii Y , Arakawa T , Shibata K , Shinagawa A , Shinozaki K
Ref : Science , 296 :141 , 2002
Abstract : Full-length complementary DNAs (cDNAs) are essential for the correct annotation of genomic sequences and for the functional analysis of genes and their products. We isolated 155,144 RIKEN Arabidopsis full-length (RAFL) cDNA clones. The 3'-end expressed sequence tags (ESTs) of 155,144 RAFL cDNAs were clustered into 14,668 nonredundant cDNA groups, about 60% of predicted genes. We also obtained 5' ESTs from 14,034 nonredundant cDNA groups and constructed a promoter database. The sequence database of the RAFL cDNAs is useful for promoter analysis and correct annotation of predicted transcription units and gene products. Furthermore, the full-length cDNAs are useful resources for analyses of the expression profiles, functions, and structures of plant proteins.
ESTHER : Seki_2002_Science_296_141
PubMedSearch : Seki_2002_Science_296_141
PubMedID: 11910074
Gene_locus related to this paper: arath-CXE15

Title : Identification of Putative M1 Muscarinic Receptors Using [3H]Pirenzepine: Characterization of Binding and Autoradiographic Localization in Human Stellate Ganglia -
Author(s) : Watson M , Roeske WR , Vickroy TW , Akiyama K , Wamsley JK , Johnson PC , Yamamura HI
Ref : Advances in Behavioral Biology , 30 :31 , 1986
PubMedID:

Title : Biochemical and functional basis of putative muscarinic receptor subtypes and its implications. -
Author(s) : Watson M , Roeske WR , Vickroy TW , Smith TL , Akiyama K , Gulya K , Duckles SP , Serra M , Adem A , Nordberg A , Gehlert DR , Wamsley JK , Yamamura HI
Ref : Trends in Pharmacological Sciences , Suppl :46 , 1986
PubMedID: