毛竹GLP基因家族成员鉴定及其表达调控研究OA

Germin-like proteins(GLPs)reinforce cell walls through cross-linking interaction.To investigate the molecular characteristics of GLP family members and their roles in cell wall cross-linking in Moso bamboo(Phyllostachys edulis),this study identified and systematically analyzed PeGLPs family members using integrated bioinformatics and molecular biology approaches.Based on RNA-Seq data associated with rapid growth of Moso bamboo and quantitative real-time PCR(qRT-PCR)assays,the expression pattern of GLP genes was analyzed,and the regulatory relationship between the transcription factor NAC and PeGLP8 was validated by the yeast one-hybrid(Y1H)and DLR(Dual luciferase reporter)assays,and the function of PeGLP8 was characterized by heterologous expression in Arabidopsis thaliana.A total of 103 GLP gene family members were identified in Moso bamboo(PeGLP1～PeGLP103).The protein domains encoded by most PeGLPs were highly conserved,encompassing three conserved Box domains.Cis-acting element prediction showed that the promoters of PeGLPs contain multiple response elements for lignin-related transcription factors,including NAC and MYB.Collinearity analysis showed that Ka/Ks ratios of most PeGLPs were less than 1.0,indicating that purifying selection has been the dominant evolutionary force shaping this family members.Phylogenetic analysis of GLPs from Moso bamboo,rice and Arabidopsis classified GLPs into seven subfamilies,with Group 7 containing the highest number of PeGLPs members(27).Based on RNA-Seq data analysis,PeGLP8 exhibited significantly different expression patterns and was co-expressed with multiple cell wall-related transcription factor genes.Among them,the expression levels of PeGLP8 and PeNAC42 showed similar trends corresponding to the degree of lignification during the rapid growth of bamboo shoots.Results from Y1H and DLR experiments confirmed that PeNAC42 can bind to the promoter of PeGLP8 and activate its expression.Heterologous overexpression of PeGLP8 in Arabidopsis led to increased plant height,cell walls thickening,significant cell elongation,and a significant increase in lignin content.It is speculated that PeGLP8 contributes to bamboo quality formation by participating in cell wall cross-linking and lignin deposition.The results of this study provide a theoretical basis for revealing the molecular mechanism underlying bamboo quality formation.