A transcriptional mediator protein that is required for activation of many RNA polymerase II promoters and is conserved from yeast to humans.
A temperature-sensitive mutation was obtained in Med6p, a component of the mediator complex from the yeast Saccharomyces cerevisiae. The mediator complex has been shown to enable transcriptional activation in vitro. This mutation in Med6p abolished activation of transcription from four of five inducible promoters tested in vivo. There was no effect, however, on uninduced transcription, transcription of constitutively expressed genes, or transcription by RNA polymerases I and III. Mediator-RNA polymerase II complex isolated from the mutant yeast strain was temperature sensitive for transcriptional activation in a reconstituted in vitro system due to a defect in initiation complex formation. A database search revealed the existence of MED6-related genes in humans and Caenorhabditis elegans, suggesting that the role of mediator in transcriptional activation is conserved throughout the evolution.
Lee
Y C
YC
Center for Basic Research, Samsung Biomedical Research Institute, Kangnam-ku, Seoul, Korea.
Min
S
S
Gim
B S
BS
Kim
Y J
YJ
D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000235:genetics; D002457:Cell Extracts; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D003067:Coenzymes; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D015966:Gene Expression Regulation, Fungal / Q000502:physiology; D005800:Genes, Fungal / Q000235:genetics; D006801:Humans; D000072235:Mating Factor; D056892:Mediator Complex; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D010452:Peptide Biosynthesis; D010455:Peptides; D010940:Plant Proteins / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012319:RNA Polymerase II / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D015533:Transcriptional Activation / Q000502:physiology*
D002352:Carrier Proteins; D002457:Cell Extracts; D003067:Coenzymes; D005656:Fungal Proteins; C107274:MED6 protein, S cerevisiae; C491485:MED6 protein, human; D056892:Mediator Complex; D026901:Membrane Transport Proteins; D010455:Peptides; D010940:Plant Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; C078729:sucrose transport protein, plant; D000072235:Mating Factor; D012319:RNA Polymerase II; D012321:DNA-Directed RNA Polymerases