Cloning and expression analysis of a bZIP cDNA in Gossypium hirsutum L.

A new full-length cDNA clone was isolated from the fiber cDNA library of Gossypium hirsutum L. The cDNA, designated GhbZIP,encoded a polypeptide of 645 amino acids. GhbZIP protein had the structure characteristics of plant bZIP proteins, including two conserved domains, DUF630 and DUF632 with unknown functions, a proline-rich domain and a phenylalanine-rich domain. Meanwhile, the protein contained a leucine zipper-like motif in DUF632. The hydropathy analysis showed that the GhbZIP was a membrane protein. GhbZIP gene was preferentially expressed in ovule and fiber cells since three days post-anthesis, as indicated it might be involved in the transcription regulation of genes during cotton fiber elongation.