[Cloning and expression analysis of a LIM-domain protein gene from cotton (Gossypium hirsuturm L.)]

LIM-domain protein plays an important role in various cellular processes, including construction of cytoskeleton, transcription control and signal transduction. Based on cotton fiber EST database and contig analysis, the coding region of a cotton LIM-domain protein gene (GhLIM1) was obtained by RT-PCR from 4DPA (day post anthesis) ovule with fiber. The cloned fragment of 848 bp contains an open reading frame of 570 bp, coding for a polypeptide of 189 amino acids. It was demonstrated that the deduced GhLIM1 protein was highly homologous to the LIM-domain protein of sunflower (Helianthus annuus), tobacco (Nicotiana tabacum) and Arabidopsis thaliana. Two intact LIM-domains, with the conserved sequence of a double zinc-finger structure (C-X2-C-X17-19-H-X2-C-X2-C-X2-C-X16-24-C-X2-H), were found in the GhLIM1 protein. RT-PCR and Northern blot analysis showed that GhLIM1 gene expressed in root, shoot tip, hypocotyls, bud, leaf, anther, ovule and fiber (4DPA, 12DPA, 18DPA). However it was preferentially expressed in the shoot tip, fiber and ovule. It was proposed that the express of GhLIM1 gene is related to cotton fiber development.