海岛棉GbPIN2基因克隆及功能解析OA

To explore the biological function of the GbPIN2 gene in cotton fiber development,this study analyzed its physicochemical properties,structure,and function using bioinformatics methods.The results showed that the auxin transporter encoded by the GbPIN2 gene consists of 602 amino acids,with a molecular weight of approximately 66.05 kDa and an isoelectric point of 8.92.Subcellular localization prediction indicated that the protein is localized in the cytoplasm.Its secondary structure was mainly composed of α-helices and random coils,and the tertiary structure exhibits a typical multimeric conformation.Prediction of cis-acting elements revealed that the GbPIN2 gene contained a large number of conserved motifs related to light response and auxin response.The expression pattern of the GbPIN2 gene in cotton fibers at different developmental stages was detected via quantitative real-time polymerase chain reaction(qRT-PCR).It was found that the expression level of GbPIN2 increased significantly and reached a peak in the middle and late stages of fiber development(20-30 d),which was consistent with the rapid elongation stage of fiber cells.In vitro cotton ovule culture experiments verified that auxin(IAA)exerts a positive regulatory effect on the expression of the GbPIN2 gene.In addition,a plant overexpression vector of the GbPIN2 gene was constructed and transformed into Arabidopsis thaliana.It was observed that the number of trichomes on the stems and leaves of GbPIN2-overexpressing Arabidopsis thaliana plants increased significantly,suggesting that the GbPIN2 gene plays an important role in regulating auxin polar transport and plant growth and development.In conclusion,this study provides a new perspective for in-depth understanding of the molecular mechanism underlying cotton fiber development,offers a potential target for improving cotton fiber quality through genetic engineering,and thus lays an important theoretical foundation for cotton genetic breeding.