关键词: 毛竹, 笋, 纤维素合成酶基因, cDNA文库, 组织表达

Abstract: The cellulose synthase gene（CesA）plays a key role in regulating cellulose biosynthesis. A 3 545 bp cDNA clone encoding PeCesA（GenBank accession No. FJ799713）was isolated from the full- length cDNA library of the shoot of Moso bamboo（Phyllostachys edulis）by PCR screen. The cDNA had an 3 243 bp open reading frame（ORF）which would be capable to encode 1 081 amino acid residues. Multiple alignment analyses showed that the PeCesA shared high similarity（over 90%）with the CesA genes from Bambusa oldhamii，Oryza sativa，Triticum aestivum and Hordeum vulgare. And the deduced amino acid sequence of PeCesA contained highly conserved two Zinc-binding domains，eight transmembrance domains and one QVLRW motif，which were special characteristics among the cellulose synthase of plant. Phylogenetic analysis showed that PeCesA was clustered in the group that included CesA4s from Bambusa oldhamii，Oryza sativa and Zea mays respectively. The expression profile of PeCesA was analyzed by quantitative Real Time PCR. The results showed that the expression of PeCesA in the top of the bamboo shoots was extremely low，but it was high in the base of shoot. And it was relatively lower in the leaves compared to the roots and stems. The results of determination of cellulose content showed there was correlation between the expression of PeCesA and the cellulose content in different organisms. It suggested that PeCesA involved in cellulose synthesis in second cell wall Moso bamboo shoots.

Key words: Phyllostachys edulis, bamboo shoot, cellulose synthase gene, cDNA library, tissue expression characterization