The cloning and sequencing of a cDNA encoding a WD repeat protein in cotton (Gossypium hirsutum L.)

In this research, one 1156 bp cDNA containing full open reading frame and encoding a novel 24-kDa protein with four tandem WD repeat motifs was cloned from cotton, therefore was named GhWDR and the GenBank accession number is AY870657. By search of GhWDR cDNA and amino acid sequences in the database, we found that GhWDR and OSJNBa0003G23.2 from Oryza sativa show 90% sequence identity and 84% identity to WD-repeat protein from Arabidopsis thaliana, and also has high sequence identity to other WD repeat proteins, most of which are similar to Pop3 from fission yeast (accession number T39922) and Lst8p from Saccharomyces cerevisiae (accession number NP014392). Therefore, we proposed that GhWDR could act in some cellular processes as pop3 or LST8 does. In addition, the expression of GhWDR in various tissues was studied by RT-PCR, and it is expressed in all of the studied tissues, but the level of expression is low in the leaves when compared to that of other tissues.