Isolation and characterization of a homeodomain-leucine zipper gene, Gmh1, from soybean somatic embryo

초록

By screening a soybean somatic embryo cDNA library with a Arabidopsis thaliana homeodomain-leucine zipper (HD-Zip) cDNA clone as a probe, we isolated a cDNA clone, Glycine max homeobox gene 1 (Gmh1), encoding a polypeptide which contains a homeodomain and a closely linked leucine zipper motif. In both nucleotide and deduced amino acid sequences, Gmh1 was highly homologous to two Arabidopsis thaliana HD-Zip genes and a tomato HD-Zip gene in HD-Zip motif. Genomic Southern blot analysis indicated that Gmh1 is a single copy gene or a member of a small gene family. Also, genomic DNA of Gmh1 has three introns, 242 bp, 261 bp and 66 bp long, respectively, in the coding region. RT-PCR and Southern hybridization revealed that Gmh1 is expressed at all organs including stems, leaves, roots, flowers, seeds and somatic embryos. These results suggest that Gmh1 protein may act as a transcriptional activator during somatic embryogenesis and seed development as well as during the development of other organs in soybean. © 1996 The Korean Society for Molecular Biology.