Drosophila Med6 is required for proliferation and metabolism associated with larval metamorphosis

다국어 초록 (Multilingual Abstract)

Mediator of transcriptional regulation is the evolutionary conserved coactivator complex that plays the central role in the integration and recruitment of diverse regulatory signals and transcription machinery to certain promoters. In yeast, each Mediator subunit is required for transcriptional regulation of a distinct group of genes. In order to elucidate the functions of metazoan Mediator proteins, we isolated mutants of a conserved Mediator subunit, Drosophila Med6(dMed6). dMed6 null homozygotes failed to pupate and died in the third larval instar. Larval mitotic cells and most imaginal discs showed severe defects in proliferation, but no apparent morphological defect was observed in other larval tissues. Clonal analysis of dMed6 mutant cells revealed that dMed6 is essential for cell viability and proliferation of most adult cell types. Drosophila cDNA microarray, quantitative RT-PCR, and in situ expression analyses of developmentally regulated genes in dMed6 mutants showed that transcriptional activation of a subset of genes involved in cell proliferation and metabolism were most affected. Our results suggest that dMed6 is required in most cells for transcriptional regulation of a subset of genes important for cell proliferation and metabolism.