Working group session:
Functional Genomics
Presentation type:
poster
Authors:
Li, Wen; Li, XueBao
Presenter:
Correspondent:
Li, XueBao
Abstract:
NAC proteins constitute one of the largest families of plant specific transcription factors (TF). They play the important roles in many biological processes such as morphogenesis, senescence, development and stress signal transduction pathways. AtXND1 (designated for XYLEM NAC Domain 1), one of the NAC family members, has been supposed as a negative regulator of secondary cell wall synthesis. In this work, a homolog of AtXND1 gene, designated GhXND1, was isolated in cotton. GhXND1 has three exons and two introns within genomic DNA sequence and encoded a polypeptide with 195 amino acids which contains the conserved features of NAC family: NAC domain and C-terminal transactivation region (TAR). GFP fluorescence assay demonstrated that GhXND1 protein is localized in cell nucleus. The C-terminus of GhXND1 has transactivation activity in yeast. GhXND1 transcripts were mainly detected in cotyleton, petal, root, hypocotyl and stem, but little or no signals of GhXND1 expression were found in other tissues. Additionally, compared with wild type (WT), overexpression of GhXND1 in Arabidopsis resulted in less number of xylem vessel cells and thinner interfascicular fibers in transgenic plants, and up-regulating the expression of KNAT7 gene and down-regulating the expression of cell wall relative genes. Overall, the data presented in this study suggested that GhXND1 may be involved in regulation of xylem development.