Abstract
PCF1-1 is a dominant suppressor of a tRNA gene A block promoter mutation (A19) in Saccharomyces cerevisiae. Transcriptional activation by PCF1-1 was examined in vitro using whole-cell extracts and purified factors derived from mutant and wild-type strains. These experiments show that PCF1 is a general activator of RNA polymerase III (pol III) gene transcription. The transcription of all pol III genes analyzed to date, including type I and numerous type II genes, is increased 3-7 fold in mutant cell extracts. Single round transcription assays indicate that the PCF1-1 mutation increases the number of functional preinitiation complexes and suggest that this is achieved by increasing the intrinsic activity of the encoded product rather than its amount. Point mutations throughout the A block of the sup3-e gene and numerous B block mutations fail to abolish transcriptional activation suggesting that interactions between TFIIIC and the internal promoter are unaffected by PCF1-1. Moreover, TFIIIC purified from the mutant strain is incapable of conferring PCF1-1 transcriptional activity to a reaction in which the remaining components are wild-type. In contrast, the activity of the TFIIIB fraction is increased in PCF1-1 extracts and can reconstitute mutant levels of transcription when added to wild-type TFIIIC and polymerase. We conclude that PCF1 is a component or regulator of TFIIIB.
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- Bartholomew B., Kassavetis G. A., Geiduschek E. P. Two components of Saccharomyces cerevisiae transcription factor IIIB (TFIIIB) are stereospecifically located upstream of a tRNA gene and interact with the second-largest subunit of TFIIIC. Mol Cell Biol. 1991 Oct;11(10):5181–5189. doi: 10.1128/mcb.11.10.5181. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Clark M. E., Dasgupta A. A transcriptionally active form of TFIIIC is modified in poliovirus-infected HeLa cells. Mol Cell Biol. 1990 Oct;10(10):5106–5113. doi: 10.1128/mcb.10.10.5106. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gabrielsen O. S., Marzouki N., Ruet A., Sentenac A., Fromageot P. Two polypeptide chains in yeast transcription factor tau interact with DNA. J Biol Chem. 1989 May 5;264(13):7505–7511. [PubMed] [Google Scholar]
- Gabrielsen O. S., Sentenac A. RNA polymerase III (C) and its transcription factors. Trends Biochem Sci. 1991 Nov;16(11):412–416. doi: 10.1016/0968-0004(91)90166-s. [DOI] [PubMed] [Google Scholar]
- Gaynor R. B., Feldman L. T., Berk A. J. Transcription of class III genes activated by viral immediate early proteins. Science. 1985 Oct 25;230(4724):447–450. doi: 10.1126/science.2996135. [DOI] [PubMed] [Google Scholar]
- Geiduschek E. P., Tocchini-Valentini G. P. Transcription by RNA polymerase III. Annu Rev Biochem. 1988;57:873–914. doi: 10.1146/annurev.bi.57.070188.004301. [DOI] [PubMed] [Google Scholar]
- Giardina C. A., Wu C. W. The identification of two antagonistic activities in a Xenopus oocyte extract that can modulate the in vitro transcription of RNA polymerase III genes. J Biol Chem. 1990 Jun 5;265(16):9121–9130. [PubMed] [Google Scholar]
- Hoeffler W. K., Kovelman R., Roeder R. G. Activation of transcription factor IIIC by the adenovirus E1A protein. Cell. 1988 Jun 17;53(6):907–920. doi: 10.1016/s0092-8674(88)90409-6. [DOI] [PubMed] [Google Scholar]
- Johnson D. L., Wilson S. L. Identification of a 150-kilodalton polypeptide that copurifies with yeast TFIIIC and binds specifically to tRNA genes. Mol Cell Biol. 1989 May;9(5):2018–2024. doi: 10.1128/mcb.9.5.2018. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kalb V. F., Jr, Bernlohr R. W. A new spectrophotometric assay for protein in cell extracts. Anal Biochem. 1977 Oct;82(2):362–371. doi: 10.1016/0003-2697(77)90173-7. [DOI] [PubMed] [Google Scholar]
- Kassavetis G. A., Bartholomew B., Blanco J. A., Johnson T. E., Geiduschek E. P. Two essential components of the Saccharomyces cerevisiae transcription factor TFIIIB: transcription and DNA-binding properties. Proc Natl Acad Sci U S A. 1991 Aug 15;88(16):7308–7312. doi: 10.1073/pnas.88.16.7308. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kassavetis G. A., Braun B. R., Nguyen L. H., Geiduschek E. P. S. cerevisiae TFIIIB is the transcription initiation factor proper of RNA polymerase III, while TFIIIA and TFIIIC are assembly factors. Cell. 1990 Jan 26;60(2):235–245. doi: 10.1016/0092-8674(90)90739-2. [DOI] [PubMed] [Google Scholar]
- Kassavetis G. A., Riggs D. L., Negri R., Nguyen L. H., Geiduschek E. P. Transcription factor IIIB generates extended DNA interactions in RNA polymerase III transcription complexes on tRNA genes. Mol Cell Biol. 1989 Jun;9(6):2551–2566. doi: 10.1128/mcb.9.6.2551. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Klekamp M. S., Weil P. A. Properties of yeast class III gene transcription factor TFIIIB. Implications regarding mechanism of action. J Biol Chem. 1987 Jun 5;262(16):7878–7883. [PubMed] [Google Scholar]
- Klekamp M. S., Weil P. A. Specific transcription of homologous class III genes in yeast-soluble cell-free extracts. J Biol Chem. 1982 Jul 25;257(14):8432–8441. [PubMed] [Google Scholar]
- Loeken M., Bikel I., Livingston D. M., Brady J. trans-activation of RNA polymerase II and III promoters by SV40 small t antigen. Cell. 1988 Dec 23;55(6):1171–1177. doi: 10.1016/0092-8674(88)90261-9. [DOI] [PubMed] [Google Scholar]
- Léveillard T., Kassavetis G. A., Geiduschek E. P. Saccharomyces cerevisiae transcription factors IIIB and IIIC bend the DNA of a tRNA(Gln) gene. J Biol Chem. 1991 Mar 15;266(8):5162–5168. [PubMed] [Google Scholar]
- Nichols M., Bell J., Klekamp M. S., Weil P. A., Söll D. Multiple mutations of the first gene of a dimeric tRNA gene abolish in vitro tRNA gene transcription. J Biol Chem. 1989 Oct 15;264(29):17084–17090. [PubMed] [Google Scholar]
- Nichols M., Willis I., Söll D. Yeast suppressor mutations and transfer RNA processing. Methods Enzymol. 1990;181:377–394. doi: 10.1016/0076-6879(90)81137-j. [DOI] [PubMed] [Google Scholar]
- Parsons M. C., Weil P. A. Purification and characterization of Saccharomyces cerevisiae transcription factor TFIIIC. Polypeptide composition defined with polyclonal antibodies. J Biol Chem. 1990 Mar 25;265(9):5095–5103. [PubMed] [Google Scholar]
- Reynolds W. F., Johnson D. L. Differential expression of oocyte-type class III genes with fraction TFIIIC from immature or mature oocytes. Mol Cell Biol. 1992 Mar;12(3):946–953. doi: 10.1128/mcb.12.3.946. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schaack J., Söll D. Transcription of a Drosophila tRNAArg gene in yeast extract: 5'-flanking sequence dependence for transcription in a heterologous system. Nucleic Acids Res. 1985 Apr 25;13(8):2803–2814. doi: 10.1093/nar/13.8.2803. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schultz P., Marzouki N., Marck C., Ruet A., Oudet P., Sentenac A. The two DNA-binding domains of yeast transcription factor tau as observed by scanning transmission electron microscopy. EMBO J. 1989 Dec 1;8(12):3815–3824. doi: 10.1002/j.1460-2075.1989.tb08559.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sprague K. U., Hagenbüchle O., Zuniga M. C. The nucleotide sequence of two silk gland alanine tRNAs: implications for fibroin synthesis and for initiator tRNA structure. Cell. 1977 Jul;11(3):561–570. doi: 10.1016/0092-8674(77)90074-5. [DOI] [PubMed] [Google Scholar]
- Stutz F., Gouilloud E., Clarkson S. G. Oocyte and somatic tyrosine tRNA genes in Xenopus laevis. Genes Dev. 1989 Aug;3(8):1190–1198. doi: 10.1101/gad.3.8.1190. [DOI] [PubMed] [Google Scholar]
- Tower J., Sollner-Webb B. Polymerase III transcription factor B activity is reduced in extracts of growth-restricted cells. Mol Cell Biol. 1988 Feb;8(2):1001–1005. doi: 10.1128/mcb.8.2.1001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Waldschmidt R., Jahn D., Seifart K. H. Purification of transcription factor IIIB from HeLa cells. J Biol Chem. 1988 Sep 15;263(26):13350–13356. [PubMed] [Google Scholar]
- White R. J., Stott D., Rigby P. W. Regulation of RNA polymerase III transcription in response to F9 embryonal carcinoma stem cell differentiation. Cell. 1989 Dec 22;59(6):1081–1092. doi: 10.1016/0092-8674(89)90764-2. [DOI] [PubMed] [Google Scholar]
- White R. J., Stott D., Rigby P. W. Regulation of RNA polymerase III transcription in response to Simian virus 40 transformation. EMBO J. 1990 Nov;9(11):3713–3721. doi: 10.1002/j.1460-2075.1990.tb07584.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Willis I., Schmidt P., Söll D. A selection for mutants of the RNA polymerase III transcription apparatus: PCF1 stimulates transcription of tRNA and 5S RNA genes. EMBO J. 1989 Dec 20;8(13):4281–4288. doi: 10.1002/j.1460-2075.1989.tb08614.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wolffe A. P., Brown D. D. Developmental regulation of two 5S ribosomal RNA genes. Science. 1988 Sep 23;241(4873):1626–1632. doi: 10.1126/science.241.4873.1626. [DOI] [PubMed] [Google Scholar]
- Wolffe A. P. RNA polymerase III transcription. Curr Opin Cell Biol. 1991 Jun;3(3):461–466. doi: 10.1016/0955-0674(91)90074-9. [DOI] [PubMed] [Google Scholar]