Abstract: Actin, a constitutively expressed protein in higher plants, was closely related to the function such as cell division, cell movement and cell signal transduction. In order to learn the relationship between characteristics and functional roles, actin genes from full-length cDNA library in Senecio scandens Buch.-Ham. ex D. were isolated, and it was found to share 96% indentity with Glycyrrhiza uralensis(GenBank accession: ABW71681.1) using bioinformatics analysis. In the present study, actin protein was composed of 360 amino acid residues with the predicted molecular weight of 40.02 kDa and the theoretical isoelectric point of 5.85. Analyses of domain and structure indicated that the protein was dominantly composed of the imperative curls and the loosed helixes, with 4 domains in three-dimensional level. The phylogenetic tree of 28 species suggested that closer relationship was observed among S.scandens, Cicer arietinum, and G.uralensis. Notably, it was concluded that actin protein might play an important role in the regulation of gene transcription in higher plants, without changeable advanced structure even if a few amino acid mutation sites.

Key words: Senecio scandens Buch.-Ham.ex D.Do, Actin gene, sequence analysis, structure prediction