Exploitation of new gene resources and genetic networks contributing to the control of crop yield-related traits,such as plant height,grain size,and shape,may enable us to breed modern high-yielding wheat varieties th...Exploitation of new gene resources and genetic networks contributing to the control of crop yield-related traits,such as plant height,grain size,and shape,may enable us to breed modern high-yielding wheat varieties through molecular methods.In this study,via ethylmethanesulfonate mutagenesis,we identify a wheat mutant plant,mu-597,that shows semi-dwarf plant architecture and round grain shape.Through bulked segregant RNA-seq and map-based cloning,the causal gene for the semi-dwarf phenotype of mu-597 is located.We find that a single-base mutation in the coding region of TaACTIN7-D(TaACT7-D),leading to a Gly-to-Ser(G65S)amino acid mutation at the 65th residue of the deduced TaACT7-D protein,can explain the semi-dwarfism and round grain shape of mu-597.Further evidence shows that the G65S mutation in TaACT7-D hinders the polymerization of actin from monomeric(G-actin)to filamentous(F-actin)status while attenuates wheat responses to multiple phytohormones,including brassinosteroids,auxin,and gibberellin.Together,these findings not only define a new semi-dwarfing gene resource that can be potentially used to design plant height and grain shape of bread wheat but also establish a direct link between actin structure modulation and phytohormone signal transduction.展开更多
Dear Editor,Introduction of gibberellin(GA)-insensitive Reduced height(Rht)genes,Rht-B1b and Rht-D1b,has resulted in the“Green Revolution”in modern wheat cultivars(Triticum aestivum)that has skyrocketed wheat grain ...Dear Editor,Introduction of gibberellin(GA)-insensitive Reduced height(Rht)genes,Rht-B1b and Rht-D1b,has resulted in the“Green Revolution”in modern wheat cultivars(Triticum aestivum)that has skyrocketed wheat grain yields worldwide since the 1960s(Peng et al.,1999;Velde et al.,2021).However,Rht-B1b/D1b also reduce coleoptiles,which is undesired in dryland regions where deep planting is essential for seedling establishment(Rebetzke et al.,1999,Rebetzke et al.,2001;Ellis et al.,2004).展开更多
Polish wheat (Triticum polonicum) is a unique tetraploid wheat species characterized by an elongated outer glume. The genetic control of the long-glume trait by a single semi-dominant locus, P1 (from Polish wheat), wa...Polish wheat (Triticum polonicum) is a unique tetraploid wheat species characterized by an elongated outer glume. The genetic control of the long-glume trait by a single semi-dominant locus, P1 (from Polish wheat), was established more than 100 years ago, but the underlying causal gene and molecular nature remain elusive. Here, we report the isolation of VRT-A2, encoding an SVP-clade MADS-box transcription factor, as the P1 candidate gene. Genetic evidence suggests that in T. polonicum, a naturally occurring sequence rearrangement in the intron-1 region of VRT-A2 leads to ectopic expression of VRT-A2 in floral organs where the long-glume phenotype appears. Interestingly, we found that the intron-1 region is a key ON/OFF molecular switch for VRT-A2 expression, not only because it recruits transcriptional repressors, but also because it confers intron-mediated transcriptional enhancement. Genotypic analyses using wheat accessions indicated that the P1 locus is likely derived from a single natural mutation in tetraploid wheat, which was subsequently inherited by hexaploid T. petropavlovskyi. Taken together, our findings highlight the promoter-proximal intron variation as a molecular basis for phenotypic differentiation, and thus species formation in Triticum plants.展开更多
基金supported by the grants from National Key Research and Development Program of China(2022YFF1003401 to Jie Liu)Hainan Yazhou Bay Seed Laboratory(B21HJ0111 to Zhongfu Ni)the National Natural Science Foundation of China(31991210 to Qixin Sun and 32072055 to Jie Liu).
文摘Exploitation of new gene resources and genetic networks contributing to the control of crop yield-related traits,such as plant height,grain size,and shape,may enable us to breed modern high-yielding wheat varieties through molecular methods.In this study,via ethylmethanesulfonate mutagenesis,we identify a wheat mutant plant,mu-597,that shows semi-dwarf plant architecture and round grain shape.Through bulked segregant RNA-seq and map-based cloning,the causal gene for the semi-dwarf phenotype of mu-597 is located.We find that a single-base mutation in the coding region of TaACTIN7-D(TaACT7-D),leading to a Gly-to-Ser(G65S)amino acid mutation at the 65th residue of the deduced TaACT7-D protein,can explain the semi-dwarfism and round grain shape of mu-597.Further evidence shows that the G65S mutation in TaACT7-D hinders the polymerization of actin from monomeric(G-actin)to filamentous(F-actin)status while attenuates wheat responses to multiple phytohormones,including brassinosteroids,auxin,and gibberellin.Together,these findings not only define a new semi-dwarfing gene resource that can be potentially used to design plant height and grain shape of bread wheat but also establish a direct link between actin structure modulation and phytohormone signal transduction.
基金This work was supported by the grants from the National Natural Science Foundation of China(grants 91935302 and 31991210)Hainan Yazhou Bay Seed Laboratory(B21HJ0111).
文摘Dear Editor,Introduction of gibberellin(GA)-insensitive Reduced height(Rht)genes,Rht-B1b and Rht-D1b,has resulted in the“Green Revolution”in modern wheat cultivars(Triticum aestivum)that has skyrocketed wheat grain yields worldwide since the 1960s(Peng et al.,1999;Velde et al.,2021).However,Rht-B1b/D1b also reduce coleoptiles,which is undesired in dryland regions where deep planting is essential for seedling establishment(Rebetzke et al.,1999,Rebetzke et al.,2001;Ellis et al.,2004).
基金This work was supported by grants from the National Natural Science Foundation of China(32072055,31991210,and 91935304).
文摘Polish wheat (Triticum polonicum) is a unique tetraploid wheat species characterized by an elongated outer glume. The genetic control of the long-glume trait by a single semi-dominant locus, P1 (from Polish wheat), was established more than 100 years ago, but the underlying causal gene and molecular nature remain elusive. Here, we report the isolation of VRT-A2, encoding an SVP-clade MADS-box transcription factor, as the P1 candidate gene. Genetic evidence suggests that in T. polonicum, a naturally occurring sequence rearrangement in the intron-1 region of VRT-A2 leads to ectopic expression of VRT-A2 in floral organs where the long-glume phenotype appears. Interestingly, we found that the intron-1 region is a key ON/OFF molecular switch for VRT-A2 expression, not only because it recruits transcriptional repressors, but also because it confers intron-mediated transcriptional enhancement. Genotypic analyses using wheat accessions indicated that the P1 locus is likely derived from a single natural mutation in tetraploid wheat, which was subsequently inherited by hexaploid T. petropavlovskyi. Taken together, our findings highlight the promoter-proximal intron variation as a molecular basis for phenotypic differentiation, and thus species formation in Triticum plants.
