关键词: 马尾松, 捕光叶绿素a/b结合蛋白基因, 序列分析, 原核表达

Abstract:

A full length cDNA of light-harvesting chlorophyll a/b(cab) gene was cloned from the first strand of Pinus massoniana cDNA through RT-PCR and RACE-PCR methods，named as cab-Pm1(GenBank accession No. GU073386). The length of cab-Pm1 is 1 062 bp，which contains an open reading frame encoding 274 amino acids，a 67 bp and a 160 bp untranslated region at 5’end and 3’end respectively，and a 25 bp Poly(A) at 3’ end. The bioinformatics analysis indicated that the pI and molecular weight of the protein encoded by cab-Pm1 were predicted to be 5.24 and 28.98 ku respectively，and the protein had one chlorophll a/b binding domain，four protein kinase C phosphorylation sites，seven N-myristoylation sites，two cAMP and cGMP-dependent protein kinase phosphorylation sites. Cab-Pm1 displayed high sequence identity with plant cab gene family isolated previously and was clustered close to cab family genes of gymnosperm plants. The prokaryotic expression vector of cab-Pm1 gene encoding protein was constructed by subcloning the fragment into pET-24a（+）and the gene was expressed in Escherichia coli induced by IPTG. The molecular weight of the induced protein was about 29 ku that was approximate as predicted.

Key words: Pinus massoniana, light harvesting chlorophyll a/b binding protein gene (cab), sequence analysis, prokaryotic expression