Cloning and expression analysis of Cucumis sativus L. CER4 involved in cuticular wax biosynthesis in cucumber

Eceriferum (cer) genes are a group of genes that have functions in wax biosynthesis, which play important roles in plant epidermal permeability, drought resistance, fertility, and organ fusion. In this study, CsCER4, an AtCER4 homologue, was cloned from cucumber (Cucumis sativus L.). The full-length cDNA of CsCER4 is 1464 bp, encoding a protein with 487 amino acid residues. CsCER4 was expressed in all analysed tissues, including leaves, male flowers, female flowers, and fruit. Its expression level among fruit development increased and then decreased, and the expression was markedly different between 3413 (glossy type cucumber) and 3401 (waxy type cucumber), suggesting that CsCER4 has a role in wax biosynthesis.