The telomere-binding protein Tbf1 demarcates snoRNA gene promoters in Saccharomyces cerevisiae.
Small nucleolar RNAs (snoRNAs) play a key role in ribosomal RNA biogenesis, yet factors controlling their expression are unknown. We found that the majority of Saccharomyces snoRNA promoters display an aRCCCTaa sequence motif at the upstream border of a TATA-containing nucleosome-free region. Genome-wide ChIP-seq analysis showed that these motifs are bound by Tbf1, a telomere-binding protein known to recognize mammalian-like T(2)AG(3) repeats at subtelomeric regions. Tbf1 has over 100 additional promoter targets, including several other genes involved in ribosome biogenesis and the TBF1 gene itself. Tbf1 is required for full snoRNA expression, yet it does not influence nucleosome positioning at snoRNA promoters. In contrast, Tbf1 contributes to nucleosome exclusion at non-snoRNA promoters, where it selectively colocalizes with the Tbf1-interacting zinc-finger proteins Vid22 and Ygr071c. Our data show that, besides the ribosomal protein gene regulator Rap1, a second telomere-binding protein also functions as a transcriptional regulator linked to yeast ribosome biogenesis.
Dipartimento di Biochimica e Biologia Molecolare, Università degli Studi di Parma, Parma, Italy.
Milena
M
Preti
Cyril
C
Ribeyre
Chiara
C
Pascali
Maria Cristina
MC
Bosio
Barbara
B
Cortelazzi
Jacques
J
Rougemont
Enrico
E
Guarnera
Felix
F
Naef
David
D
Shore
Giorgio
G
Dieci
D001483:Base Sequence; D019295:Computational Biology; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics*; D020537:RNA, Small Nucleolar / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D004268:DNA-Binding Proteins; D020537:RNA, Small Nucleolar; D029701:Saccharomyces cerevisiae Proteins; C079376:TBF1 protein, S cerevisiae; D014157:Transcription Factors