Screening And Gene Cloning Of CtBP/BARs Enhancer From Arabidopsis Thaliana

Cells are the basic unit of organ morphology,and the formation of plant organs requires processes such as cell proliferation and tissue differentiation.Arabidopsis petals have functions such as regulating pollination and light reflex,and also play an important role in the reproductive organs.However,relative roots,hypocotyls and cotyledons,the study in the mechanism of petal morphogenesis is extremely rare.Arabidopsis ANGUSTIFOLIA(AN)is a homolog protein to the Cterminal binding protein/protein transport inhibitor A-ADP ribosylation substrate(CtBP/BARs)in mammals,and the working mechanism of AN is still unclear.The mutant an-2 of AN in Arabidopsis thaliana has the characteristics of cotyledons thickening and narrowing,reduced trichome branching,root spiral growth and other traits.But so far,it is unclear how AN regulates the shape of petals.In this study,the seeds were mutagenized of ethyl methanesulfonate(EMS),and the mutant ocean1/an-2(OCEAN1,Organ Control Enhancer of an-2)was screened and the single mutant ocean1 was isolated.Relative to wild-type Col-0,ocean1 cotyledons are narrowed and curled,and the petals become narrow.ocean1/an-2 further enhances the an-2 phenotype,and the cotyledons and petals become more narrow and thick.At the cellular level,there was a significant zigzag mosaic between the Col-0 and ocean1 cotyledon epithelial cells,and the edge of the an-2 cotyledon epithelial cells was significantly reduced.Compared with the single mutant ocean1 and an-2,the serrated structure of the ocean1/an-2 plating cells disappeared.In the petals,the ocean1/an-2 base cells appeared narrow and the area increased significantly,and the top of the cone cells became more inflated.The microtubules in the Col-0 and mutant ocean1 conical cells were arranged in a spiral order,while the microtubule arrangement of an-2 and ocean1/an-2 became disordered.The study in this paper found that AN is likely to affect the morphogenesis of cells by affecting the arrangement of microtubules,and ultimately regulate the development of organs.As an enhancer of an-2,OCEAN1 participates in the morphological development of Arabidopsis leaves and floral organs with AN.