Evidence for a posttranscriptional role of a TFIIICalpha-like protein in Chironomus tentans
2002 (English)In: Molecular Biology of the Cell, ISSN 1059-1524, E-ISSN 1939-4586, Vol. 13, no 5, 1765-1777 p.Article in journal (Refereed) Published
We have cloned and sequenced a cDNA that encodes for a nuclear protein of 238 kDa in the dipteran Chironomus tentans. This protein, that we call p2D10, is structurally similar to the alpha subunit of the general transcription factor TFIIIC. Using immunoelectron microscopy we have shown that a fraction of p2D10 is located at sites of transcription, which is consistent with a possible role of this protein in transcription initiation. We have also found that a large fraction of p2D10 is located in the nucleoplasm and in the nuclear pore complexes. Using gel filtration chromatography and coimmunoprecipitation methods, we have identified and characterized two p2D10-containing complexes that differ in molecular mass and composition. The heavy p2D10-containing complex contains at least one other component of the TFIIIC complex, TFIIIC-epsilon. Based on its molecular mass and composition, the heavy p2D10-containing complex may be the Pol III holoenzyme. The light p2D10-containing complex contains RNA together with at least two proteins that are thought to be involved in mRNA trafficking, RAE1 and hrp65. The observations reported here suggest that this new TFIIIC-alpha-like protein is involved in posttranscriptional steps of premRNA metabolism in Chironomus tentans.
Place, publisher, year, edition, pages
2002. Vol. 13, no 5, 1765-1777 p.
Amino Acid Motifs, Animals, Chironomidae/genetics/*physiology, Insect Proteins/genetics/*physiology, Macromolecular Substances, Multigene Family, Nuclear Matrix-Associated Proteins/metabolism, Nuclear Proteins/genetics/metabolism/*physiology, Nucleocytoplasmic Transport Proteins/metabolism, RNA Processing; Post-Transcriptional, Salivary Glands, Sequence Analysis; Protein, Transcription Factors; TFIII/chemistry
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-10414DOI: 10.1091/mbc.01-09-0436PubMedID: 12006668OAI: oai:DiVA.org:uu-10414DiVA: diva2:38182