Abstract:Squalene content is one of evaluation standards for high quality edible oil. Squalene synthase is the directly upstream regulation key enzyme for squalene synthesis. In this study, based on the transcriptome database of Camellia oleifera seed kernel, the specific primers were designed and full-length cDNA clone was obtained by RACE. The cDNA was named CoSQS (GenBank accession No. JX914592). The results of bioinformatics analysis showed that: the cDNA full-length was 1554 bp with a 1245 bp-open reading frame, the gene encoded 415 amino acid residues. CoSQS protein was alkalescent non-secreted protein with two transmembrane regions and two specific signal area of squalene and phytoene synthase. CoSQS protein had the closest relationship with Diospyros kaki DkSQS and belonged to a hydrophobic protein. Real time fluorescent quantitative PCR analysis showed that: during May to October, the CoSQS expression firstly up-regulation and later down-regulation. The transcription peak was in late September. CoSQS gene expression was closely related with squalene content ,but no significant correlation with oil yield.