Structure of the yeast TAP1 protein: dependence of transcription activation on the DNA context of the target gene.
Sequence data are presented for the Saccharomyces cerevisiae TAP1 gene and for a mutant allele, tap1-1, that activates transcription of the promoter-defective yeast SUP4 tRNA(Tyr) allele SUP4A53T61. The degree of in vivo activation of this allele by tap1-1 is strongly affected by the nature of the flanking DNA sequences at 5'-flanking DNA sequences as far away as 413 bp from the tRNA gene and by 3'-flanking sequences as well. We considered the possibility that this dependency is related to the nature of the chromatin assembled on these different flanking sequences. TAP1 encodes a protein 1,006 amino acids long. The tap1-1 mutation consists of a thymine-to-cytosine DNA change that changes amino acid 683 from tyrosine to histidine. Recently, Amberg et al. reported the cloning and sequencing of RAT1, a yeast gene identical to TAP1, by complementation of a mutant defect in poly(A) RNA export from the nucleus to the cytoplasm (D. C. Amberg, A. L. Goldstein, and C. N. Cole, Genes Dev. 6:1173-1189, 1992). The RAT1/TAP1 gene product has extensive sequence similarity to a yeast DNA strand transfer protein that is also a riboexonuclease (variously known as KEM1, XRN1, SEP1, DST2, or RAR5; reviewed by Kearsey and Kipling [Trends Cell Biol. 1:110-112, 1991]). The tap1-1 amino acid substitution affects a region of the protein in which KEM1 and TAP1 are highly similar in sequence.
Department of Genetics, University of Washington, Seattle 98195.
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Aldrich
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Di Segni
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McConaughy
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Keen
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Whelen
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Hall
D000595:Amino Acid Sequence; D001483:Base Sequence; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism*; D005095:Exoribonucleases; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism*; D015870:Gene Expression; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D012365:RNA, Transfer, Tyr / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic
D004271:DNA, Fungal; D005656:Fungal Proteins; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D012365:RNA, Transfer, Tyr; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; C075577:RAT1 protein, S cerevisiae; D005095:Exoribonucleases; C068398:XRN1 protein, S cerevisiae