Al-Babili S

References (25)

Title : New Series of Zaxinone Mimics (MiZax) for Fundamental and Applied Research - Jamil_2023_Biomolecules_13_
Author(s) : Jamil M , Lin PY , Berqdar L , Wang JY , Takahashi I , Ota T , Alhammad N , Chen GE , Asami T , Al-Babili S
Ref : Biomolecules , 13 : , 2023
Abstract : The apocarotenoid zaxinone is a recently discovered regulatory metabolite required for proper rice growth and development. In addition, zaxinone and its two mimics (MiZax3 and MiZax5) were shown to have a remarkable growth-promoting activity on crops and a capability to reduce infestation by the root parasitic plant Striga through decreasing strigolactone (SL) production, suggesting their potential for application in agriculture and horticulture. In the present study, we developed a new series of MiZax via structural modification of the two potent zaxinone mimics (MiZax3 and MiZax5) and evaluated their effect on plant growth and Striga infestation. In general, the structural modifications to MiZax3 and MiZax5 did not additionally improve their overall performance but caused an increase in certain activities. In conclusion, MiZax5 and especially MiZax3 remain the likely most efficient zaxinone mimics for controlling Striga infestation.
ESTHER : Jamil_2023_Biomolecules_13_
PubMedSearch : Jamil_2023_Biomolecules_13_
PubMedID: 37627271

Title : Does zaxinone counteract strigolactones in shaping rice architecture? - Wang_2023_Plant.Signal.Behav_18_2184127
Author(s) : Wang JY , Braguy J , Al-Babili S
Ref : Plant Signal Behav , 18 :2184127 , 2023
Abstract : The cleavage of plant carotenoids leads to apocarotenoids, a group of metabolites including precursors of the hormones strigolactones (SLs) and abscisic acid, regulatory and signaling molecules. Zaxinone is a recently discovered apocarotenoid growth regulator that improves growth and suppress SL biosynthesis in rice (Oryza sativa). To test if zaxinone also counteracts the growth regulatory effects of SLs in rice, we co-supplied zaxinone and the synthetic SL analog rac-GR24 to the rice SL-deficient DWARF17 (d17) mutant. Results showed that co-application of GR24 and zaxinone still rescued d17 phenotype, indicating that zaxinone and GR24 act independently in regulating root and shoot growth and development in rice.
ESTHER : Wang_2023_Plant.Signal.Behav_18_2184127
PubMedSearch : Wang_2023_Plant.Signal.Behav_18_2184127
PubMedID: 36855265

Title : Zaxinone mimics (MiZax) efficiently promote growth and production of potato and strawberry plants under desert climate conditions - Wang_2023_Sci.Rep_13_17438
Author(s) : Wang JY , Jamil M , AlOtaibi TS , Abdelaziz ME , Ota T , Ibrahim OH , Berqdar L , Asami T , Ahmed Mousa MA , Al-Babili S
Ref : Sci Rep , 13 :17438 , 2023
Abstract : Climate changes and the rapid expanding human population have become critical concerns for global food security. One of the promising solutions is the employment of plant growth regulators (PGRs) for increasing crop yield and overcoming adverse growth conditions, such as desert climate. Recently, the apocarotenoid zaxinone and its two mimics (MiZax3 and MiZax5) have shown a promising growth-promoting activity in cereals and vegetable crops under greenhouse and field conditions. Herein, we further investigated the effect of MiZax3 and MiZax5, at different concentrations (5 and 10 microM in 2021; 2.5 and 5 microM in 2022), on the growth and yield of the two valuable vegetable crops, potato and strawberry, in the Kingdom of Saudi of Arabia. Application of both MiZax significantly increased plant agronomic traits, yield components and total yield, in five independent field trials from 2021 to 2022. Remarkably, the amount of applied MiZax was far less than humic acid, a widely applied commercial compound used here for comparison. Hence, our results indicate that MiZax are very promising PGRs that can be applied to promote the growth and yield of vegetable crops even under desert conditions and at relatively low concentrations.
ESTHER : Wang_2023_Sci.Rep_13_17438
PubMedSearch : Wang_2023_Sci.Rep_13_17438
PubMedID: 37838798

Title : Rational design of Striga hermonthica-specific seed germination inhibitors - Zarban_2022_Plant.Physiol_188_1369
Author(s) : Zarban RA , Hameed UFS , Jamil M , Ota T , Wang JY , Arold ST , Asami T , Al-Babili S
Ref : Plant Physiol , 188 :1369 , 2022
Abstract : The obligate hemiparasitic weed Striga hermonthica grows on cereal roots and presents a severe threat to global food security by causing enormous yield losses, particularly in sub-Saharan Africa. The rapidly increasing Striga seed bank in infested soils provides a major obstacle in controlling this weed. Striga seeds require host-derived strigolactones (SLs) for germination, and corresponding antagonists could be used as germination inhibitors. Recently, we demonstrated that the common detergent Triton X-100 is a specific inhibitor of Striga seed germination by binding noncovalently to its receptor, S. hermonthica HYPO-SENSITIVE TO LIGHT 7 (ShHTL7), without blocking the rice (Oryza sativa) SL receptor DWARF14 (OsD14). Moreover, triazole ureas, the potent covalently binding antagonists of rice SL perception with much higher activity toward OsD14, showed inhibition of Striga but were less specific. Considering that Triton X-100 is not suitable for field application and by combining structural elements of Triton and triazole urea, we developed two hybrid compounds, KK023-N1 and KK023-N2, as potential Striga-specific germination inhibitors. Both compounds blocked the hydrolysis activity of ShHTL7 but did not affect that of OsD14. Binding of KK023-N1 diminished ShHTL7 interaction with S. hermonthica MORE AXILLARY BRANCHING 2, a major component in SL signal transduction, and increased ShHTL7 thermal specificity. Docking studies indicate that KK023-N1 binding is not covalent but is caused by hydrophobic interactions. Finally, in vitro and greenhouse tests revealed specific inhibition of Striga seed germination, which led to a 38% reduction in Striga infestation in pot experiments. These findings reveal that KK023-N1 is a potential candidate for combating Striga and a promising basis for rational design and development of further Striga-specific herbicides.
ESTHER : Zarban_2022_Plant.Physiol_188_1369
PubMedSearch : Zarban_2022_Plant.Physiol_188_1369
PubMedID: 34850204
Gene_locus related to this paper: strhe-ShHTL7

Title : Ultrahigh-Performance Liquid Chromatography-Mass Spectrometry Analysis of Carotenoid-Derived Hormones and Apocarotenoids in Plants - Mi_2022_Curr.Protoc_2_e375
Author(s) : Mi J , Liew KX , Al-Babili S
Ref : Curr Protoc , 2 :e375 , 2022
Abstract : Carotenoid oxidative cleavage products, apocarotenoids (APOs), are a class of important plant secondary metabolites, which include phytohormones abscisic acid (ABA) and strigolactones (SLs), and growth regulators and signaling molecules such as beta-cyclocitral, zaxinone, anchorene, beta-apo-11-carotenoids, and retinal. Qualitative and quantitative analysis of these bioactive compounds is crucial for understanding their metabolism and may also enable discovering further regulatory APOs. The state-of-the-art mass spectrometry (MS) technology has advanced the detection of plant APOs; however, it is still challenging to perform an accurate analysis of the low-level phytohormones ABA and SL and the structurally diverse APOs from complex plant matrices. Here, we describe ultrahigh-performance liquid chromatography-MS (UHPLC-MS) methods to determine carotenoid-derived hormones and APOs from plants by integrating ultrasound-assisted extraction and solid-phase extraction. These assays enable an accurate quantification of carotenoid-derived hormones and APOs from plant tissues by using an UHPLC hybrid quadrupole-Orbitrap mass spectrometer. 2022 Wiley Periodicals LLC. Basic Protocol 1: UHPLC-MS analysis of APOs from rice roots Support Protocol: Preparation of dried plant root powder Basic Protocol 2: UHPLC-MS analysis of SLs from rice roots Basic Protocol 3: UHPLC-MS analysis of ABA from rice roots.
ESTHER : Mi_2022_Curr.Protoc_2_e375
PubMedSearch : Mi_2022_Curr.Protoc_2_e375
PubMedID: 35201678

Title : Evaluation of the Biostimulant Activity of Zaxinone Mimics (MiZax) in Crop Plants - Wang_2022_Front.Plant.Sci_13_874858
Author(s) : Wang JY , Jamil M , Hossain MG , Chen GE , Berqdar L , Ota T , Blilou I , Asami T , Al-Solimani SJ , Mousa MAA , Al-Babili S
Ref : Front Plant Sci , 13 :874858 , 2022
Abstract : Global food security is a critical concern that needs practical solutions to feed the expanding human population. A promising approach is the employment of biostimulants to increase crop production. Biostimulants include compounds that boost plant growth. Recently, mimics of zaxinone (MiZax) were shown to have a promising growth-promoting effect in rice (Oryza sativa). In this study, we investigated the effect of MiZax on the growth and yield of three dicot horticultural plants, namely, tomato (Solanum lycopersicum), capsicum (Capsicum annuum), and squash (Cucurbita pepo) in different growth environments, as well as on the growth and development of the monocot date palm (Phoenix dactylifera), an important crop in the Middle East. The application of MiZax significantly enhanced plant height, flower, and branch numbers, fruit size, and total fruit yield in independent field trials from 2020 to 2021. Importantly, the amount of applied MiZax was far less than that used with the commercial compound humic acid, a widely used biostimulant in horticulture. Our results indicate that MiZax have significant application potential to improve the performance and productivity of horticultural crops.
ESTHER : Wang_2022_Front.Plant.Sci_13_874858
PubMedSearch : Wang_2022_Front.Plant.Sci_13_874858
PubMedID: 35783933

Title : A structural homologue of the plant receptor D14 mediates responses to strigolactones in the fungal phytopathogen Cryphonectria parasitica - Fiorilli_2022_New.Phytol__
Author(s) : Fiorilli V , Forgia M , de Saint Germain A , D'Arrigo G , Cornu D , Le Bris P , Al-Babili S , Cardinale F , Prandi C , Spyrakis F , Boyer FD , Turina M , Lanfranco L
Ref : New Phytol , : , 2022
Abstract : Strigolactones (SLs) are plant hormones and important signaling molecules required to promote the arbuscular mycorrhizal (AM) symbiosis. While in plants an alpha/beta-hydrolase, DWARF14 (D14), was shown to act as a receptor that binds and cleaves SLs, the fungal receptor for SLs is unknown. Since AM fungi are currently not genetically tractable, in this study, we used the fungal pathogen Cryphonectria parasitica for which gene deletion protocols exist, as a model, as we have previously shown that it responds to SLs. By means of computational, biochemical and genetic analyses we identified a D14 structural homologue, CpD14. Molecular homology modelling and docking support the prediction that CpD14 interacts with and hydrolyses SLs. The recombinant CpD14 protein shows alpha/beta hydrolytic activity in vitro against the SLs synthetic analogue GR24; its enzymatic activity requires an intact Ser/His/Asp catalytic triad. CpD14 expression in the d14-1 loss-of-function Arabidopsis thaliana line did not rescue the plant mutant phenotype. However, gene inactivation by knock-out homologous recombination reduced fungal sensitivity to SLs. These results indicate that CpD14 is involved in SLs responses in C. parasitica and strengthen the role of SLs as multifunctional molecules acting in plant microbe-interactions.
ESTHER : Fiorilli_2022_New.Phytol__
PubMedSearch : Fiorilli_2022_New.Phytol__
PubMedID: 35119708
Gene_locus related to this paper: crypa-CpD14

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 : Striga hermonthica Suicidal Germination Activity of Potent Strigolactone Analogs: Evaluation from Laboratory Bioassays to Field Trials - Jamil_2022_Plants.(Basel)_11__
Author(s) : Jamil M , Wang JY , Yonli D , Ota T , Berqdar L , Traore H , Margueritte O , Zwanenburg B , Asami T , Al-Babili S
Ref : Plants (Basel) , 11 : , 2022
Abstract : The obligate hemiparasite Striga hermonthica is one of the major global biotic threats to agriculture in sub-Saharan Africa, causing severe yield losses of cereals. The germination of Striga seeds relies on host-released signaling molecules, mainly strigolactones (SLs). This dependency opens up the possibility of deploying SL analogs as "suicidal germination agents" to reduce the accumulated seed bank of Striga in infested soils. Although several synthetic SL analogs have been developed for this purpose, the utility of these compounds in realizing the suicidal germination strategy for combating Striga is still largely unknown. Here, we evaluated the efficacy of three potent SL analogs (MP3, MP16, and Nijmegen-1) under laboratory, greenhouse, and farmer's field conditions. All investigated analogs showed around a 50% Striga germination rate, equivalent to a 50% reduction in infestation, which was comparable to the standard SL analog GR24. Importantly, MP16 had the maximum reduction of Striga emergence (97%) in the greenhouse experiment, while Nijmegen-1 appeared to be a promising candidate under field conditions, with a 43% and 60% reduction of Striga emergence in pearl millet and sorghum fields, respectively. These findings confirm that the selected SL analogs appear to make promising candidates as simple suicidal agents both under laboratory and real African field conditions, which may support us to improve suicidal germination technology to deplete the Striga seed bank in African agriculture.
ESTHER : Jamil_2022_Plants.(Basel)_11__
PubMedSearch : Jamil_2022_Plants.(Basel)_11__
PubMedID: 35448773

Title : A Protoplast-Based Bioassay to Quantify Strigolactone Activity in Arabidopsis Using StrigoQuant - Braguy_2021_Methods.Mol.Biol_2309_201
Author(s) : Braguy J , Samodelov SL , Andres J , Ochoa-Fernandez R , Al-Babili S , Zurbriggen MD
Ref : Methods Mol Biol , 2309 :201 , 2021
Abstract : Understanding the biological background of strigolactone (SL) structural diversity and the SL signaling pathway at molecular level requires quantitative and sensitive tools that precisely determine SL dynamics. Such biosensors may be also very helpful in screening for SL analogs and mimics with defined biological functions.Recently, the genetically encoded, ratiometric sensor StrigoQuant was developed and allowed the quantification of the activity of a wide concentration range of SLs. StrigoQuant can be used for studies on the biosynthesis, function and signal transduction of this hormone class.Here, we provide a comprehensive protocol for establishing the use of StrigoQuant in Arabidopsis protoplasts. We first describe the generation and transformation of the protoplasts with StrigoQuant and detail the application of the synthetic SL analogue GR24. We then show the recording of the luminescence signal and how the obtained data are processed and used to assess/determine SL perception.
ESTHER : Braguy_2021_Methods.Mol.Biol_2309_201
PubMedSearch : Braguy_2021_Methods.Mol.Biol_2309_201
PubMedID: 34028689

Title : Multi-omics approaches explain the growth-promoting effect of the apocarotenoid growth regulator zaxinone in rice - Wang_2021_Commun.Biol_4_1222
Author(s) : Wang JY , Alseekh S , Xiao T , Ablazov A , Perez de Souza L , Fiorilli V , Anggarani M , Lin PY , Votta C , Novero M , Jamil M , Lanfranco L , Hsing YC , Blilou I , Fernie AR , Al-Babili S
Ref : Commun Biol , 4 :1222 , 2021
Abstract : The apocarotenoid zaxinone promotes growth and suppresses strigolactone biosynthesis in rice. To shed light on the mechanisms underlying its growth-promoting effect, we employed a combined omics approach integrating transcriptomics and metabolomics analysis of rice seedlings treated with zaxinone, and determined the resulting changes at the cellular and hormonal levels. Metabolites as well as transcripts analysis demonstrate that zaxinone application increased sugar content and triggered glycolysis, the tricarboxylic acid cycle and other sugar-related metabolic processes in rice roots. In addition, zaxinone treatment led to an increased root starch content and induced glycosylation of cytokinins. The transcriptomic, metabolic and hormonal changes were accompanied by striking alterations of roots at cellular level, which showed an increase in apex length, diameter, and the number of cells and cortex cell layers. Remarkably, zaxinone did not affect the metabolism of roots in a strigolactone deficient mutant, suggesting an essential role of strigolactone in the zaxinone growth-promoting activity. Taken together, our results unravel zaxinone as a global regulator of the transcriptome and metabolome, as well as of hormonal and cellular composition of rice roots. Moreover, they suggest that zaxinone promotes rice growth most likely by increasing sugar uptake and metabolism, and reinforce the potential of this compound in increasing rice performance.
ESTHER : Wang_2021_Commun.Biol_4_1222
PubMedSearch : Wang_2021_Commun.Biol_4_1222
PubMedID: 34697384

Title : Efficient Mimics for Elucidating Zaxinone Biology and Promoting Agricultural Applications - Wang_2020_Mol.Plant_13_1654
Author(s) : Wang JY , Jamil M , Lin PY , Ota T , Fiorilli V , Novero M , Zarban RA , Kountche BA , Takahashi I , Martinez C , Lanfranco L , Bonfante P , de Lera AR , Asami T , Al-Babili S
Ref : Mol Plant , 13 :1654 , 2020
Abstract : Zaxinone is an apocarotenoid regulatory metabolite required for normal rice growth and development. In addition, zaxinone has a large application potential in agriculture, due to its growth-promoting activity and capability to alleviate infestation by the root parasitic plant Striga through decreasing strigolactone (SL) production. However, zaxinone is poorly accessible to the scientific community because of its laborious organic synthesis that impedes its further investigation and utilization. In this study, we developed easy-to-synthesize and highly efficient mimics of zaxinone (MiZax). We performed a structure-activity relationship study using a series of apocarotenoids distinguished from zaxinone by different structural features. Using the obtained results, we designed several phenyl-based compounds synthesized with a high-yield through a simple method. Activity tests showed that MiZax3 and MiZax5 exert zaxinone activity in rescuing root growth of a zaxinone-deficient rice mutant, promoting growth, and reducing SL content in roots and root exudates of wild-type plants. Moreover, these compounds were at least as efficient as zaxinone in suppressing transcript level of SL biosynthesis genes and in alleviating Striga infestation under greenhouse conditions, and did not negatively impact mycorrhization. Taken together, MiZax are a promising tool for elucidating zaxinone biology and investigating rice development, and suitable candidates for combating Striga and increasing crop growth.
ESTHER : Wang_2020_Mol.Plant_13_1654
PubMedSearch : Wang_2020_Mol.Plant_13_1654
PubMedID: 32835886

Title : The Apocarotenoid Zaxinone Is a Positive Regulator of Strigolactone and Abscisic Acid Biosynthesis in Arabidopsis Roots - Ablazov_2020_Front.Plant.Sci_11_578
Author(s) : Ablazov A , Mi J , Jamil M , Jia KP , Wang JY , Feng Q , Al-Babili S
Ref : Front Plant Sci , 11 :578 , 2020
Abstract : Carotenoids are ubiquitous precursors of important metabolites including hormones, such as strigolactones (SLs) and abscisic acid (ABA), and signaling and regulatory molecules, such as the recently discovered zaxinone. Strigolactones and ABA are key regulators of plant growth and development, adaptation to environmental changes and response to biotic and abiotic stress. Previously, we have shown that zaxinone, an apocarotenoid produced in rice by the enzyme zaxinone synthase (ZAS) that is common in mycorrhizal plants, is required for normal rice growth and development, and a negative regulator of SL biosynthesis. Zaxinone is also formed in Arabidopsis, which lacks ZAS, via an unknown route. In the present study, we investigated the biological activity of zaxinone in Arabidopsis, focusing on its effect on SL and ABA biosynthesis. For this purpose, we quantified the content of both hormones and determined the levels of related transcripts in Arabidopsis (Arabidopsis thaliana), roots upon zaxinone treatment. For SL quantification, we also employed Striga seed germination bioassay. Results obtained show that zaxinone application to hydroponically grown Arabidopsis seedlings enhanced transcript levels of key biosynthetic genes of both hormones, led to higher root ABA and SL (methyl carlactonoate, MeCLA) content, and increased SL release, even under sufficient phosphate supply. Using the SL insensitive (max2-1) and the ABA deficient (aba1-6, aba2-1, and nced3) mutants, we also show that zaxinone application reduced hypocotyl growth and that this effect is caused by increasing ABA content. Our results suggest that zaxinone is a regulatory metabolite also in Arabidopsis, which triggers the biosynthesis of both carotenoid-derived hormones, SLs and ABA, in roots. In the non-mycotrophic plant Arabidopsis, zaxinone does not increase growth and may be perceived as a stress signal, while it acts as a growth-promoting metabolite and suppressor of SL biosynthesis in rice.
ESTHER : Ablazov_2020_Front.Plant.Sci_11_578
PubMedSearch : Ablazov_2020_Front.Plant.Sci_11_578
PubMedID: 32477389

Title : A New Series of Carlactonoic Acid Based Strigolactone Analogs for Fundamental and Applied Research - Jamil_2020_Front.Plant.Sci_11_434
Author(s) : Jamil M , Kountche BA , Wang JY , Haider I , Jia KP , Takahashi I , Ota T , Asami T , Al-Babili S
Ref : Front Plant Sci , 11 :434 , 2020
Abstract : Strigolactones (SLs) are a group of carotenoid derived plant hormones that play a key role in establishing plant architecture and adapting it to environmental changes, and are involved in plants response to biotic and abiotic stress. SLs are also released into the soil to serve as a chemical signal attracting beneficial mycorrhizal fungi. However, this signal also induces seed germination in root parasitic weeds that represent a major global threat for agriculture. This wide spectrum of biological functions has made SL research one of the most important current topics in fundamental and applied plant science. The availability of SLs is crucial for investigating SL biology as well as for agricultural application. However, natural SLs are produced in very low amounts, and their organic synthesis is quite difficult, which creates a need for efficient and easy-to-synthesize analogs and mimics. Recently, we have generated a set of SL analogs, Methyl Phenlactonoates (MPs), which resemble the non-canonical SL carlactonoic acid. In this paper, we describe the development and characterization of a new series of easy-to-synthesize MPs. The new analogs were assessed with respect to regulation of shoot branching, impact on leaf senescence, and induction of seed germination in different root parasitic plants species. Some of the new analogs showed higher efficiency in inhibiting shoot branching as well as in triggering parasitic seed germination, compared to the commonly used GR24. MP16 was the most outstanding analog showing high activity in different SL biological functions. In summary, our new analogs series contains very promising candidates for different applications, which include the usage in studies for understanding different aspects of SL biology as well as large scale field application for combating root parasitic weeds, such as Striga hermonthica that devastates cereal yields in sub-Saharan Africa.
ESTHER : Jamil_2020_Front.Plant.Sci_11_434
PubMedSearch : Jamil_2020_Front.Plant.Sci_11_434
PubMedID: 32373143

Title : The apocarotenoid metabolite zaxinone regulates growth and strigolactone biosynthesis in rice - Wang_2019_Nat.Commun_10_810
Author(s) : Wang JY , Haider I , Jamil M , Fiorilli V , Saito Y , Mi J , Baz L , Kountche BA , Jia KP , Guo X , Balakrishna A , Ntui VO , Reinke B , Volpe V , Gojobori T , Blilou I , Lanfranco L , Bonfante P , Al-Babili S
Ref : Nat Commun , 10 :810 , 2019
Abstract : Carotenoid cleavage dioxygenases (CCDs) form hormones and signaling molecules. Here we show that a member of an overlooked plant CCD subfamily from rice, that we name Zaxinone Synthase (ZAS), can produce zaxinone, a novel apocarotenoid metabolite in vitro. Loss-of-function mutants (zas) contain less zaxinone, exhibit retarded growth and showed elevated levels of strigolactones (SLs), a hormone that determines plant architecture, mediates mycorrhization and facilitates infestation by root parasitic weeds, such as Striga spp. Application of zaxinone can rescue zas phenotypes, decrease SL content and release and promote root growth in wild-type seedlings. In conclusion, we show that zaxinone is a key regulator of rice development and biotic interactions and has potential for increasing crop growth and combating Striga, a severe threat to global food security.
ESTHER : Wang_2019_Nat.Commun_10_810
PubMedSearch : Wang_2019_Nat.Commun_10_810
PubMedID: 30778050

Title : Methylation at the C-3' in D-Ring of Strigolactone Analogs Reduces Biological Activity in Root Parasitic Plants and Rice - Jamil_2019_Front.Plant.Sci_10_353
Author(s) : Jamil M , Kountche BA , Haider I , Wang JY , Aldossary F , Zarban RA , Jia KP , Yonli D , Shahul Hameed UF , Takahashi I , Ota T , Arold ST , Asami T , Al-Babili S
Ref : Front Plant Sci , 10 :353 , 2019
Abstract : Strigolactones (SLs) regulate plant development and induce seed germination in obligate root parasitic weeds, e.g. Striga spp. Because organic synthesis of natural SLs is laborious, there is a large need for easy-to-synthesize and efficient analogs. Here, we investigated the effect of a structural modification of the D-ring, a conserved structural element in SLs. We synthesized and investigated the activity of two analogs, MP13 and MP26, which differ from previously published AR8 and AR36 only in the absence of methylation at C-3'. The de-methylated MP13 and MP26 were much more efficient in regulating plant development and inducing Striga seed germination, compared with AR8. Hydrolysis assays performed with purified Striga SL receptor and docking of AR8 and MP13 to the corresponding active site confirmed and explained the higher activity. Field trials performed in a naturally Striga-infested African farmer's field unraveled MP13 as a promising candidate for combating Striga by inducing germination in host's absence. Our findings demonstrate that methylation of the C-3' in D-ring in SL analogs has a negative impact on their activity and identify MP13 and, particularly, MP26 as potent SL analogs with simple structures, which can be employed to control Striga, a major threat to global food security.
ESTHER : Jamil_2019_Front.Plant.Sci_10_353
PubMedSearch : Jamil_2019_Front.Plant.Sci_10_353
PubMedID: 31001294

Title : Methyl phenlactonoates are efficient strigolactone analogs with simple structure - Jamil_2018_J.Exp.Bot_69_2319
Author(s) : Jamil M , Kountche BA , Haider I , Guo X , Ntui VO , Jia KP , Ali S , Hameed US , Nakamura H , Lyu Y , Jiang K , Hirabayashi K , Tanokura M , Arold ST , Asami T , Al-Babili S
Ref : J Exp Bot , 69 :2319 , 2018
Abstract : Strigolactones (SLs) are a new class of phytohormones that also act as germination stimulants for root parasitic plants, such as Striga spp., and as branching factors for symbiotic arbuscular mycorrhizal fungi. Sources for natural SLs are very limited. Hence, efficient and simple SL analogs are needed for elucidating SL-related biological processes as well as for agricultural applications. Based on the structure of the non-canonical SL methyl carlactonoate, we developed a new, easy to synthesize series of analogs, termed methyl phenlactonoates (MPs), evaluated their efficacy in exerting different SL functions, and determined their affinity for SL receptors from rice and Striga hermonthica. Most of the MPs showed considerable activity in regulating plant architecture, triggering leaf senescence, and inducing parasitic seed germination. Moreover, some MPs outperformed GR24, a widely used SL analog with a complex structure, in exerting particular SL functions, such as modulating Arabidopsis roots architecture and inhibiting rice tillering. Thus, MPs will help in elucidating the functions of SLs and are promising candidates for agricultural applications. Moreover, MPs demonstrate that slight structural modifications clearly impact the efficiency in exerting particular SL functions, indicating that structural diversity of natural SLs may mirror a functional specificity.
ESTHER : Jamil_2018_J.Exp.Bot_69_2319
PubMedSearch : Jamil_2018_J.Exp.Bot_69_2319
PubMedID: 29300919

Title : Structural basis for specific inhibition of the highly sensitive ShHTL7 receptor - Shahul Hameed_2018_EMBO.Rep_19_e45619
Author(s) : Shahul Hameed U , Haider I , Jamil M , Kountche BA , Guo X , Zarban RA , Kim D , Al-Babili S , Arold ST
Ref : EMBO Rep , : , 2018
Abstract : Striga hermonthica is a root parasitic plant that infests cereals, decimating yields, particularly in sub-Saharan Africa. For germination, Striga seeds require host-released strigolactones that are perceived by the family of HYPOSENSITIVE to LIGHT (ShHTL) receptors. Inhibiting seed germination would thus be a promising approach for combating Striga However, there are currently no strigolactone antagonists that specifically block ShHTLs and do not bind to DWARF14, the homologous strigolactone receptor of the host. Here, we show that the octyl phenol ethoxylate Triton X-100 inhibits S. hermonthica seed germination without affecting host plants. High-resolution X-ray structures reveal that Triton X-100 specifically plugs the catalytic pocket of ShHTL7. ShHTL7-specific inhibition by Triton X-100 demonstrates the dominant role of this particular ShHTL receptor for Striga germination. Our structural analysis provides a rationale for the broad specificity and high sensitivity of ShHTL7, and reveals that strigolactones trigger structural changes in ShHTL7 that are required for downstream signaling. Our findings identify Triton and the related 2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]acetic acid as promising lead compounds for the rational design of efficient Striga-specific herbicides.
ESTHER : Shahul Hameed_2018_EMBO.Rep_19_e45619
PubMedSearch : Shahul Hameed_2018_EMBO.Rep_19_e45619
PubMedID: 30021834
Gene_locus related to this paper: strhe-ShHTL7

Title : Synthetic strigolactone analogues reveal anti-cancer activities on hepatocellular carcinoma cells - Hasan_2018_Bioorg.Med.Chem.Lett_28_1077
Author(s) : Hasan MN , Choudhry H , Razvi SS , Moselhy SS , Kumosani TA , Zamzami MA , Omran Z , Halwani MA , Al-Babili S , Abualnaja KO , Al-Malki AL , Alhosin M , Asami T
Ref : Bioorganic & Medicinal Chemistry Lett , 28 :1077 , 2018
Abstract : Hepatocellular carcinoma (HCC) remains one of the leading causes of death worldwide. The complex etiology is attributed to many factors like heredity, cirrhosis, hepatitis infections or the dysregulation of the different molecular pathways. Nevertheless, the current treatment regimens have either severe side effects or tumors gradually acquire resistance upon prolonged use. Thus, developing a new selective treatment for HCC is the need of the hour. Many anticancer agents derived from plants have been evaluated for their cytotoxicity towards many human cancer cell lines. Strigolactones (SLs)-a newly discovered class of phytohormones, play a crucial role in the development of plant-root and shoot. Recently, many synthetic analogues of SLs have demonstrated pro-apoptotic effects on different cancer cell lines like prostate, breast, colon and lung. In this study, we tested synthetic SLs analogues on HCC cell line-HepG2 and evaluated their capability to induce cell proliferation inhibition and apoptosis. Primary WST-1 assays, followed by annexin-V/7AAD staining, demonstrated the anti-proliferative effects. The SLs analogues TIT3 and TIT7 were found to significantly reduce HepG2 cell viability in a dose- and time-dependent manner and induce apoptosis. Interestingly, though TIT3 and TIT7 strongly affected cancer cell proliferation, both compounds showed moderate anti-proliferative effect on normal cells. Further, migration of cancer cells was suppressed upon treatment with TIT3 and TIT7 in a wound healing assay. In summary, these findings suggest that two SLs analogues TIT3 and TIT7 exert selective inhibitory effects on cancer cells most likely through targeting microtubules. SLs analogues could be used in future as potential anti-cancer candidates in chemotherapy.
ESTHER : Hasan_2018_Bioorg.Med.Chem.Lett_28_1077
PubMedSearch : Hasan_2018_Bioorg.Med.Chem.Lett_28_1077
PubMedID: 29456109

Title : Insights into the formation of carlactone from in-depth analysis of the CCD8-catalyzed reactions - Bruno_2017_FEBS.Lett_591_792
Author(s) : Bruno M , Vermathen M , Alder A , Wust F , Schaub P , van der Steen R , Beyer P , Ghisla S , Al-Babili S
Ref : FEBS Letters , 591 :792 , 2017
Abstract : Strigolactones are a new class of phytohormones synthesized from carotenoids via carlactone. The complex structure of carlactone is not easily deducible from its precursor, a cis-configured beta-carotene cleavage product, and is thus formed via a poorly understood series of reactions and molecular rearrangements, all catalyzed by only one enzyme, the carotenoid cleavage dioxygenase 8 (CCD8). Moreover, the reactions leading to carlactone are expected to form a second, yet unidentified product. In this study, we used (13) C and (18) O-labeling to shed light on the reactions catalyzed by CCD8. The characterization of the resulting carlactone by LC-MS and NMR, and the identification of the assumed, less accessible second product allowed us to formulate a minimal reaction mechanism for carlactone generation.
ESTHER : Bruno_2017_FEBS.Lett_591_792
PubMedSearch : Bruno_2017_FEBS.Lett_591_792
PubMedID: 28186640

Title : Nitro-Phenlactone, a Carlactone Analog with Pleiotropic Strigolactone Activities -
Author(s) : Jia KP , Kountche BA , Jamil M , Guo X , Ntui VO , Rufenacht A , Rochange S , Al-Babili S
Ref : Mol Plant , 9 :1341 , 2016
PubMedID: 27288318

Title : Strigolactones, a novel carotenoid-derived plant hormone - Al-Babili_2015_Annu.Rev.Plant.Biol_66_161
Author(s) : Al-Babili S , Bouwmeester HJ
Ref : Annu Rev Plant Biol , 66 :161 , 2015
Abstract : Strigolactones (SLs) are carotenoid-derived plant hormones and signaling molecules. When released into the soil, SLs indicate the presence of a host to symbiotic fungi and root parasitic plants. In planta, they regulate several developmental processes that adapt plant architecture to nutrient availability. Highly branched/tillered mutants in Arabidopsis, pea, and rice have enabled the identification of four SL biosynthetic enzymes: a cis/trans-carotene isomerase, two carotenoid cleavage dioxygenases, and a cytochrome P450 (MAX1). In vitro and in vivo enzyme assays and analysis of mutants have shown that the pathway involves a combination of new reactions leading to carlactone, which is converted by a rice MAX1 homolog into an SL parent molecule with a tricyclic lactone moiety. In this review, we focus on SL biosynthesis, describe the hormonal and environmental factors that determine this process, and discuss SL transport and downstream signaling as well as the role of SLs in regulating plant development.
ESTHER : Al-Babili_2015_Annu.Rev.Plant.Biol_66_161
PubMedSearch : Al-Babili_2015_Annu.Rev.Plant.Biol_66_161
PubMedID: 25621512

Title : Rice cytochrome P450 MAX1 homologs catalyze distinct steps in strigolactone biosynthesis - Zhang_2014_Nat.Chem.Biol_10_1028
Author(s) : Zhang Y , van Dijk AD , Scaffidi A , Flematti GR , Hofmann M , Charnikhova T , Verstappen F , Hepworth J , van der Krol S , Leyser O , Smith SM , Zwanenburg B , Al-Babili S , Ruyter-Spira C , Bouwmeester HJ
Ref : Nat Chemical Biology , 10 :1028 , 2014
Abstract : Strigolactones (SLs) are a class of phytohormones and rhizosphere signaling compounds with high structural diversity. Three enzymes, carotenoid isomerase DWARF27 and carotenoid cleavage dioxygenases CCD7 and CCD8, were previously shown to convert all-trans-beta-carotene to carlactone (CL), the SL precursor. However, how CL is metabolized to SLs has remained elusive. Here, by reconstituting the SL biosynthetic pathway in Nicotiana benthamiana, we show that a rice homolog of Arabidopsis More Axillary Growth 1 (MAX1), encodes a cytochrome P450 CYP711 subfamily member that acts as a CL oxidase to stereoselectively convert CL into ent-2'-epi-5-deoxystrigol (B-C lactone ring formation), the presumed precursor of rice SLs. A protein encoded by a second rice MAX1 homolog then catalyzes the conversion of ent-2'-epi-5-deoxystrigol to orobanchol. We therefore report that two members of CYP711 enzymes can catalyze two distinct steps in SL biosynthesis, identifying the first enzymes involved in B-C ring closure and a subsequent structural diversification step of SLs.
ESTHER : Zhang_2014_Nat.Chem.Biol_10_1028
PubMedSearch : Zhang_2014_Nat.Chem.Biol_10_1028
PubMedID: 25344813

Title : The path from beta-carotene to carlactone, a strigolactone-like plant hormone - Alder_2012_Science_335_1348
Author(s) : Alder A , Jamil M , Marzorati M , Bruno M , Vermathen M , Bigler P , Ghisla S , Bouwmeester H , Beyer P , Al-Babili S
Ref : Science , 335 :1348 , 2012
Abstract : Strigolactones, phytohormones with diverse signaling activities, have a common structure consisting of two lactones connected by an enol-ether bridge. Strigolactones derive from carotenoids via a pathway involving the carotenoid cleavage dioxygenases 7 and 8 (CCD7 and CCD8) and the iron-binding protein D27. We show that D27 is a beta-carotene isomerase that converts all-trans-beta-carotene into 9-cis-beta-carotene, which is cleaved by CCD7 into a 9-cis-configured aldehyde. CCD8 incorporates three oxygens into 9-cis-beta-apo-10'-carotenal and performs molecular rearrangement, linking carotenoids with strigolactones and producing carlactone, a compound with strigolactone-like biological activities. Knowledge of the structure of carlactone will be crucial for understanding the biology of strigolactones and may have applications in combating parasitic weeds.
ESTHER : Alder_2012_Science_335_1348
PubMedSearch : Alder_2012_Science_335_1348
PubMedID: 22422982

Title : Microevolution in cyanobacteria: re-sequencing a motile substrain of Synechocystis sp. PCC 6803 - Trautmann_2012_DNA.Res_19_435
Author(s) : Trautmann D , Voss B , Wilde A , Al-Babili S , Hess WR
Ref : DNA Research , 19 :435 , 2012
Abstract : Synechocystis sp. PCC 6803 is a widely used model cyanobacterium for studying photosynthesis, phototaxis, the production of biofuels and many other aspects. Here we present a re-sequencing study of the genome and seven plasmids of one of the most widely used Synechocystis sp. PCC 6803 substrains, the glucose tolerant and motile Moscow or 'PCC-M' strain, revealing considerable evidence for recent microevolution. Seven single nucleotide polymorphisms (SNPs) specifically shared between 'PCC-M' and the 'PCC-N and PCC-P' substrains indicate that 'PCC-M' belongs to the 'PCC' group of motile strains. The identified indels and SNPs in 'PCC-M' are likely to affect glucose tolerance, motility, phage resistance, certain stress responses as well as functions in the primary metabolism, potentially relevant for the synthesis of alkanes. Three SNPs in intergenic regions could affect the promoter activities of two protein-coding genes and one cis-antisense RNA. Two deletions in 'PCC-M' affect parts of clustered regularly interspaced short palindrome repeats-associated spacer-repeat regions on plasmid pSYSA, in one case by an unusual recombination between spacer sequences.
ESTHER : Trautmann_2012_DNA.Res_19_435
PubMedSearch : Trautmann_2012_DNA.Res_19_435
PubMedID: 23069868
Gene_locus related to this paper: synsp-ester , 9sync-m1mb45