Molecular Cloning and Characterization of a β-Galactosidase Gene Expressed Preferentially in Cotton Fibers  

作　　者：Heng-MuZHANG Jin-YuanLIU 

机构地区：[1]LaboratoryofMolecularBiologyandProteinScienceLaboratoryoftheMinistryofEducation,DepartmentofBiologicalSciencesandBioteehnology,TsinghuaUniversity,Beijing100084,China

出　　处：《Journal of Integrative Plant Biology》2005年第2期223-232,共10页植物学报（英文版）

基　　金：国家高技术研究发展计划(863计划)，国家重点基础研究发展计划(973计划)，中国博士后科学基金

摘　　要：β-galactosidases (EC 3.2.1.23) constitute a widespread family of enzymes in plants that is thought to be involved in metabolism of cell wall polysaccharides. We reported herein the isolation of a fulllength cDNA encoding a typical β-galactosidase protein, designated GhGal1 (Gossypium hirsutum L.galactosidase), of 843 amino acids with a predicted molecular mass of nearly 94.8 kDa. In addition to a glycosyl hydrolase family 35 domain and a putative signal peptide, an unusual characteristic of GhGal 1 is that, at the C-terminus of the enzyme, a domain was found that is structurally related to a sea urchin egg lectin (SUEL-lectin) with D-galactose- and L-rhamnose-binding domains. Based on results from Southern blot, we estimated that there would be two copies of the GhGal1 gene per haploid genome of G. hirsutum.The transcripts of GhGal1 were regulated spatially and temporally and were present in very high abundance at the elongation stage of the cotton fiber. The expression pattern suggests that the GhGal1 gene could be involved in metabolism of the primary cell wall.

关 键 词：cotton fiber elongation β-galactosidase gene lectin-like motif. 

分 类 号：S562[农业科学—作物学]