Homeodomain-leucine zipper (HD-Zip) proteins are transcriptional factors involved in plant development. In this study, one cDNA clone (Gossypium hirsutum homeoboxl, designated GhHB1) encoding HD-Zip protein was isolated from a cotton root cDNA library. The GhHB1 cDNA is 1132 bp in length, including an 828 bp open reading frame that encodes a peptide with 275 amino acids, and 5'-/3'- untranslated regions. The predicted GhHB1 protein containing a homeodomaln and a leucine-rich zipper motif shares relatively high identity with other plant HD...