elt-1, a gene encoding a Caenorhabditis elegans GATA transcription factor,is highly expressed in the germ lines with msp genes as the potential targets

The Caenorhabditis elegans ELT-1 protein, a homolog of the vertebrate GATA transcription factor family, is a transcription activator that can recogniz e the GATA motif, We previously showed that the elt-1 mRNA was primarily ex pressed in C, elegans embryos. To examine whether the elt-1 mRNA in embryos is maternal, paternal or zygotic, Northern blot analysis was performed wit h RNA isolated from the C, elegans germ-line mutant strains, fem-2 (b245)lf , fem-3 (q20)gf, him-3 (e1489), and glp-4 (bn2), This analysis revealed tha t the high level of elt-1 mRNA in the C, elegans embryos resulted from eith er the maternal or the paternal transcription, rather than from the zygotic expression. These results further demonstrated that elt-1 was highly expre ssed in the germ-line of both sexes, To investigate the possible target gen es for the ELT-1 protein in the germ line, the ELT-1 protein was expressed and tested for its binding specificity to the GATA motif that is present in the promoter region of the C, elegans major sperm protein genes. It was fo und that two conserved cis-elements, AGATCT and AGATAA, in the proximal pro moter region of the msp-113 gene provided the best recognition site for ELT -I, Mutational analysis showed that the GATC core sequence was necessary fo r strong transactivation of the reporter gene, and that the combination of GATC and GATA motif resulted in a stronger transactivation by ELT-1 than ei ther the duplicated GATC or GATA motif, These results suggest that the pote ntial target for the ELT-1 protein in the germ-line may be one of the major sperm protein gene family.