A study of biochemical and functional interactions of Htl1p, a putative component of the Saccharomyces cerevisiae, Rsc chromatin-remodeling complex.
HTL1, a small gene of Saccharomyces cerevisiae, encodes a 78-aminoacid peptide that influences the performance of a wide range of cellular processes [Lanzuolo, C., Ederle, S., Pollice, A., Russo, F., Storlazzi, A., Pulitzer, J.F., 2001. The HTL1 gene,YCR020W-b of Saccharomyces cerevisiae is necessary for growth at 37 degrees C, and for the conservation of chromosome stability and fertility. Yeast, 18, 1317-1330]. Genetic interactions and co-immunoprecipitation experiments indicate a role for Htl1p in functions controlled by RSC, a multiprotein, ATP-dependent, chromatin-remodeling complex [Lu, Y.M., Lin, Y.R., Tsai, A., Hsao, Y.S., Li, C.C., Cheng, M.Y., 2003. Dissecting the pet18 mutation in Saccharomyces cerevisiae: HTL1 encodes a 7-kDa polypeptide that interacts with components of the RSC complex. Mol. Genet. Genomics., 269, 321-330] [Romeo, M.J., Angus-Hill, M.L., Sobering, A.K., Kamada, Y., Cairns, B.R., Levin, D.E., 2002. HTL1 encodes a novel factor that interacts with the Rsc chromatin-remodeling complex in Saccharomyces cerevisiae. Mol. Cell. Biol., 22, 8165-8174]. Htl1p and RSC components, share the property of associating with TBP a component of general multiprotein transcription factor TFIID [Sanders, S.L., Jennings, J., Canutescu, A., Link, A.J., Weil, P.A., 2002. Proteomics of the eukaryotic transcription machinery: identification of proteins associated with components of yeast TFIID by multidimensional mass spectrometry. Mol. Cell. Biol. 22, 4723-4738]. We confirm, by integrating genetic and biochemical experiments, that Htl1p binding to the RSC complex is direct and physiologically relevant and show that it is mediated by Rsc8p, a core component of the RSC complex. Deletion of HTL1, like depletion of RSC core subunits [Moreira, J.M., Holmberg, S., 1999. Transcriptional repression of the yeast CHA1 gene requires the chromatin-remodeling complex Rsc. Embo J., 18, 2836-2844], leads to constitutive transcription of the CHA1 locus. This transcriptional phenotype exhibits variable penetrance. Deletion of HTL1 also leads to hydroxyurea hypersensitivity at 30 degrees C, suggesting a defect in replication/repair. This defect leads, during cell growth, to selection of mutations at the SIR3 locus that suppress hydroxyurea sensitivity.
Florio
Carolina
C
Università degli Studi di Napoli Federico II, Dipartimento di Biologia, Via Cinthia-80126-Naples, Italy.
Moscariello
Mario
M
Ederle
Sara
S
Fasano
Rossella
R
Lanzuolo
Chiara
C
Pulitzer
John F
JF
D000595:Amino Acid Sequence; D001483:Base Sequence; D018797:Cell Cycle Proteins; D042002:Chromatin Assembly and Disassembly; D004271:DNA, Fungal / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D025141:Drug Resistance, Fungal / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005559:Formamides / Q000494:pharmacology; D005800:Genes, Fungal; D006918:Hydroxyurea / Q000494:pharmacology; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
D018797:Cell Cycle Proteins; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005559:Formamides; C469779:HTL1 protein, S cerevisiae; D009687:Nuclear Proteins; C103337:RSC complex, S cerevisiae; D011994:Recombinant Proteins; C084122:SIR3 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; D014157:Transcription Factors; C031066:formamide; D006918:Hydroxyurea