Wright RJ

References (4)

Title : Repeated polyploidization of Gossypium genomes and the evolution of spinnable cotton fibres - Paterson_2012_Nature_492_423
Author(s) : Paterson AH , Wendel JF , Gundlach H , Guo H , Jenkins J , Jin D , Llewellyn D , Showmaker KC , Shu S , Udall J , Yoo MJ , Byers R , Chen W , Doron-Faigenboim A , Duke MV , Gong L , Grimwood J , Grover C , Grupp K , Hu G , Lee TH , Li J , Lin L , Liu T , Marler BS , Page JT , Roberts AW , Romanel E , Sanders WS , Szadkowski E , Tan X , Tang H , Xu C , Wang J , Wang Z , Zhang D , Zhang L , Ashrafi H , Bedon F , Bowers JE , Brubaker CL , Chee PW , Das S , Gingle AR , Haigler CH , Harker D , Hoffmann LV , Hovav R , Jones DC , Lemke C , Mansoor S , ur Rahman M , Rainville LN , Rambani A , Reddy UK , Rong JK , Saranga Y , Scheffler BE , Scheffler JA , Stelly DM , Triplett BA , Van Deynze A , Vaslin MF , Waghmare VN , Walford SA , Wright RJ , Zaki EA , Zhang T , Dennis ES , Mayer KF , Peterson DG , Rokhsar DS , Wang X , Schmutz J
Ref : Nature , 492 :423 , 2012
Abstract : Polyploidy often confers emergent properties, such as the higher fibre productivity and quality of tetraploid cottons than diploid cottons bred for the same environments. Here we show that an abrupt five- to sixfold ploidy increase approximately 60 million years (Myr) ago, and allopolyploidy reuniting divergent Gossypium genomes approximately 1-2 Myr ago, conferred about 30-36-fold duplication of ancestral angiosperm (flowering plant) genes in elite cottons (Gossypium hirsutum and Gossypium barbadense), genetic complexity equalled only by Brassica among sequenced angiosperms. Nascent fibre evolution, before allopolyploidy, is elucidated by comparison of spinnable-fibred Gossypium herbaceum A and non-spinnable Gossypium longicalyx F genomes to one another and the outgroup D genome of non-spinnable Gossypium raimondii. The sequence of a G. hirsutum A(t)D(t) (in which 't' indicates tetraploid) cultivar reveals many non-reciprocal DNA exchanges between subgenomes that may have contributed to phenotypic innovation and/or other emergent properties such as ecological adaptation by polyploids. Most DNA-level novelty in G. hirsutum recombines alleles from the D-genome progenitor native to its New World habitat and the Old World A-genome progenitor in which spinnable fibre evolved. Coordinated expression changes in proximal groups of functionally distinct genes, including a nuclear mitochondrial DNA block, may account for clusters of cotton-fibre quantitative trait loci affecting diverse traits. Opportunities abound for dissecting emergent properties of other polyploids, particularly angiosperms, by comparison to diploid progenitors and outgroups.
ESTHER : Paterson_2012_Nature_492_423
PubMedSearch : Paterson_2012_Nature_492_423
PubMedID: 23257886
Gene_locus related to this paper: gosra-a0a0d2qg22 , gosra-a0a0d2w3z1 , gosra-a0a0d2uuz7 , gosra-a0a0d2rxs2 , gosra-a0a0d2sdk0 , gosra-a0a0d2tng2 , gosra-a0a0d2twz7 , gosra-a0a0d2vdc5 , gosra-a0a0d2vj24 , gosra-a0a0d2sr31 , goshi-a0a1u8knd1 , goshi-a0a1u8nhw9 , goshi-a0a1u8kis4 , gosra-a0a0d2pul0 , gosra-a0a0d2p3f2 , gosra-a0a0d2ril5 , gosra-a0a0d2s7d5 , gosra-a0a0d2t9b3 , gosra-a0a0d2tw88 , gosra-a0a0d2umz5 , gosra-a0a0d2pzd7 , gosra-a0a0d2scu7 , gosra-a0a0d2vcx6

Title : Larval susceptibility of an insecticide-resistant western corn rootworm (Coleoptera: Chrysomelidae) population to soil insecticides: laboratory bioassays, assays of detoxification enzymes, and field performance - Wright_2000_J.Econ.Entomol_93_7
Author(s) : Wright RJ , Scharf ME , Meinke LJ , Zhou X , Siegfried BD , Chandler LD
Ref : J Econ Entomol , 93 :7 , 2000
Abstract : Soil insecticides were evaluated in laboratory and field studies against larvae of an insecticide resistant population (Phelps County, NE) of western corn rootworm, Diabrotica virgifera virgifera LeConte. Insecticide toxicity was evaluated by topical application of technical insecticides to 3rd instars from Saunders County, NE (susceptible) and Phelps County populations. Resistance ratios (LD50 Phelps County/LD50 Saunders County) for the insecticides methyl parathion, tefluthrin, carbofuran, terbufos, and chlorpyrifos were 28.0, 9.3, 8.7, 2.6 and 1.3, respectively. Biochemical investigation of suspected enzymatic resistance mechanisms in 3rd instars identified significant elevation of esterase activity (alpha and beta naphthyl acetate hydrolysis [3.8- and 3.9-fold]). Examination of 3rd instar esterases by native PAGE identified increased intensity of several isoenzymes in the resistant population. Assays of cytochrome P450 activity (4-CNMA demethylation and aldrin epoxidation) did not identify elevated activity in resistant 3rd instars. Granular soil insecticides were applied at planting to corn, Zea mays L., in replicated field trials in 1997 and 1998 at the same Phelps County site as the source of resistant rootworms for the laboratory studies. In 1997, planting time applications of Counter 20CR, Counter 15 G (terbufos), and Lorsban 15 G (chlorpyrifos) resulted in the lowest root injury ratings (1-6 Iowa scale); 2.50, 2.55, 2.65, respectively (untreated check root rating of 4.55). In 1998, all insecticides performed similarly against a lower rootworm density (untreated check root rating of 3.72). These studies suggest that resistance previously documented in adults also is present in 3rd instars, esterases are possibly involved as resistance mechanisms, and resistance to methyl parathion in adults is also evident in larvae, but does not confer cross-resistance in larvae to all organophosphate insecticides.
ESTHER : Wright_2000_J.Econ.Entomol_93_7
PubMedSearch : Wright_2000_J.Econ.Entomol_93_7
PubMedID: 14658504

Title : Metabolism of Carbaryl by Insecticide-Resistant and -Susceptible Western Corn Rootworm Populations (Coleoptera: Chrysomelidae) - Scharf_1999_Pestic.Biochem.Physiol_63_85
Author(s) : Scharf ME , Meinke LJ , Wright RJ , Chandler LD , Siegfried BD
Ref : Pesticide Biochemistry and Physiology , 63 :85 , 1999
Abstract : Metabolic and integumental mechanisms of carbaryl resistance were investigated using [14C] carbaryl in three western corn rootworm populations from Nebraska (two resistant and one susceptible). In diagnostic concentration bioassays of carbaryl toxicity, mortality was 94% for the susceptible population, and 63 and 29% for the resistant populations; confirming the presence of resistance as previously characterized. Penetration of carbaryl through the integument of the three populations was not different, suggesting that there are no integumental barriers involved in the resistance.In vivodistribution studies did not identify any notable differences between populations except increased excretion rates in the resistant populations.In vivometabolism studies identified more substantial increases in the disappearance of carbaryl and in naphthyl acetamide formation for the resistant populations.In vitromicrosomal metabolism of carbaryl resulted in increased NADPH-dependent disappearance of carbaryl and in formation of naphthyl acetamide and naphthol for both resistant populations.In vitrometabolism of carbaryl by soluble proteins identified increased naphthol formation (via hydrolysis) in both resistant populations, and increased polar metabolites in the presence of reduced glutathione for one of the resistant populations. Based on their apparent lack of interaction with the parent compound carbaryl, glutathioneS-transferases appear to have an exclusive role in conjugation of secondary metabolites. Although qualitative differences are apparent between the two resistant populations studied, results indicate the primary importance of both cytochrome P450 monooxygenases and esterases in carbaryl resistance.
ESTHER : Scharf_1999_Pestic.Biochem.Physiol_63_85
PubMedSearch : Scharf_1999_Pestic.Biochem.Physiol_63_85

Title : Mechanisms of Methyl and Ethyl Parathion Resistance in the Western Corn Rootworm (Coleoptera: Chrysomelidae) - Miota_1998_Pestic.Biochem.Physiol_61_39
Author(s) : Miota F , Scharf ME , Ono M , Marcon P , Meinke LJ , Wright RJ , Chandler LD , Siegfried BD
Ref : Pesticide Biochemistry and Physiology , 61 :39 , 1998
Abstract : The mechanisms of methyl parathion and ethyl parathion resistance were studied in two populations (Phelps and York) of western corn rootworm adults (Diabrotica virgifera virgiferaLe Conte). Results of these studies indicate that the resistance is due to the combined effects of metabolic detoxification and target site insensitivity and that different processes are involved in conferring resistance in the two resistant populations. Resistance to methyl parathion is partially suppressible by the hydrolytic enzyme inhibitor DEF in both resistant populations, suggesting involvement of hydrolytic enzymes, and is in agreement with the increased general esterase activity toward naphtholic ester substrates observed in both resistant populations. Resistance was also partially suppressed by the monooxygenase inhibitor piperonyl butoxide (PBO), but only in the York population. This suppression of the resistance by PBO is consistent with the significantly higher cytochrome P-450-dependent activities (epoxidation andN-demethylation) that were observed in the York population.In vivometabolism experiments with 14C-labeled ethyl parathion confirm involvement of metabolic detoxification in the resistance based on differences in the rates of metabolite formation in both resistant populations. However, the York and Phelps populations again displayed significant differences in the overall pharmacokinetics and profiles of metabolite formation, indicating that the two populations employ different resistance mechanisms. Comparison of acetylcholinesterase inhibition by methyl paraoxon among the resistant and susceptible populations indicated that only the Phelps population possessed a decrease in sensitivity to inhibition (twofold). Therefore, we conclude that increased metabolic detoxification by NADPH-dependent monooxygenases and general esterases confers resistance to the York population, while acetylcholinesterase insensitivity and hydrolytic metabolism interact to confer resistance in the Phelps population.
ESTHER : Miota_1998_Pestic.Biochem.Physiol_61_39
PubMedSearch : Miota_1998_Pestic.Biochem.Physiol_61_39