查看更多>>摘要:Background Cotton fiber is a model tissue for studying microtubule-associated proteins(MAPs).The Xklp2(TPX2)proteins that belong to the novel MAPs member mainly participate in the formation and development of microtubule(MT).However,there is a lack of studies concerning the systematic characterization of the TPX2 genes family in cotton.Therefore,the identification and portrayal of G.hirsutum TPX2 genes can provide key targets for molecular manipula-tion in the breeding of cotton fiber improvement.Result In this study,TPX2 family genes were classified into two distinct subclasses TPXLs and MAP genes WAVE DAMP-ENED2-LIKE(WDLs)and quite conservative in quantity.GhWDL3 was significantly up-regulated in 15 days post anthe-sis fibers of ZRI-015(an upland cotton with longer and stronger fiber).GhWDL3 promotes all stem hairs to become straight when overexpressed in Arabidopsis,which may indirectly regulate cotton fiber cell morphology during fiber development.Virus induced gene silencing(VIGS)results showed that GhWDL3 inhibited fiber cell elongation at fiber development periods through regulating the expression of cell wall related genes.Conclusion These results reveal that GhWDL3 regulated cotton fiber cell elongation and provide crucial information for the further investigation in the regulatory mechanisms/networks of cotton fiber length.
查看更多>>摘要:Background Cotton is an economically important crop.It is crucial to find an effective method to improve cot-ton yield,and one approach is to decrease the abscission of cotton bolls and buds.However,the lack of knowl-edge of the genetic and molecular mechanisms underlying cotton boll abscission traits has hindered genetic improvements.Results Pearson's correlation analysis revealed a significant positive correlation between boll abscission rates 1(AR1)and boll abscission rates 2(AR2).A genome-wide association study was conducted on 145 loci that exhibited high polymorphism and were uniformly distributed across 26 chromosomes(pair).The study revealed 18,46,and 62 markers that were significantly associated with boll abscission,fiber quality,and yield traits(P<0.05),explaining 1.75%-7.13%,1.16%-9.58%,and 1.40%-5.44%of the phenotypic variation,respectively.Notably,the marker MON_SHIN-1584b was associated with the cotton boll abscission trait,whereas MON_CGR5732a was associated with cotton boll abscission and fiber quality traits.Thirteen of the marker loci identified in this study had been previously reported.Based on phenotypic effects,six typical cultivars with elite alleles related to cotton boll abscission,fiber quality,and yield traits were identified.These cultivars hold great promise for widespread utilization in breeding programs.Conclusions These results lay the foundation for understanding the molecular regulatory mechanism of cotton boll abscission and provide data for the future improvement of cotton breeding.
查看更多>>摘要:Cotton,an important industrial crop cultivated in more than 70 countries,plays a major role in the livelihood of millions of farmers and industrialists.Cotton is mainly grown for its fiber,an economic component that can be differentiated from its epidermal cells in the outer integument of a developing seed.Fiber length,fiber strength,and fiber fineness are three main attributes that contribute to the quality of cotton fibers.Recent advancements in genomics have identi-fied key genes,which are the most important factors that govern these three traits,can be introduced into cultivars of interest via gene editing,marker-assisted selection,and transgenics,thus the narrow genetic background of cotton can be addressed and its fiber quality traits can be enhanced.Over the past two decades,quantitative trait loci(QTLs)have been mapped for different fiber traits,approximately 1 850 QTLs have been mapped for fiber length,fiber strength,and fineness among which a few genes have been edited for quality improvement in cotton.In this back-ground,the current review covers the development and the factors that influence these traits,along with the reported genes,QTLs,and the edited genomes for trait improvement.