TY - JOUR
T1 - An essential yeast gene encoding a TTAGGG repeat-binding protein
AU - Brigati, C.
AU - Kurtz, S.
AU - Balderes, D.
AU - Vidali, G.
AU - Shore, D.
PY - 1993
Y1 - 1993
N2 - A yeast gene encoding a DNA-binding protein that recognizes the telomeric repeat sequence TTAGGG found in multicellular eukaryotes was identified by screening a λgt11 expression library with a radiolabeled TTAGGG multimer. This gene, which we refer to as TBF1 (TTAGGG repeat-binding factor 1), encodes a polypeptide with a predicted molecular mass of 63 kDa. The TBF1 protein, produced in vitro by transcription and translation of the cloned gene, binds to (TTAGGG)(n) probes and to a yeast telomeric junction sequence that contains two copies of the sequence TTAGGG separated by 5 bp. TBF1 appears to be identical to a previously described yeast TTAGGG-repeat binding activity called TBFα. TBF1 produced in vitro yields protein-DNA complexes with (TTAGGG)(n) probes that have mobilities on native polyacrylamide gels identical to those produced by partially purified TBFα from yeast cells. Furthermore, when extracts are prepared from a strain containing a TBF1 gene with an antigen tag, we find that the antigen copurifies with the predominant (TTAGGG)(n)-binding activity in the extracts. The DNA sequence of TBF1 was determined. The predicted protein sequence suggests that TBF1 may contain a nucleotide-binding domain, but no significant similarities to any other known proteins were identified, nor was an obvious DNA-binding motif apparent. Diploid cells heterozygous for a tbf1::URA3 insertion mutation are viable but upon sporulation give rise to tetrads with only two viable spores, both of which are Ura-, indicating that the TBF1 gene is essential for growth. Possible functions of TBF1 (TFBα) are discussed in light of these new results.
AB - A yeast gene encoding a DNA-binding protein that recognizes the telomeric repeat sequence TTAGGG found in multicellular eukaryotes was identified by screening a λgt11 expression library with a radiolabeled TTAGGG multimer. This gene, which we refer to as TBF1 (TTAGGG repeat-binding factor 1), encodes a polypeptide with a predicted molecular mass of 63 kDa. The TBF1 protein, produced in vitro by transcription and translation of the cloned gene, binds to (TTAGGG)(n) probes and to a yeast telomeric junction sequence that contains two copies of the sequence TTAGGG separated by 5 bp. TBF1 appears to be identical to a previously described yeast TTAGGG-repeat binding activity called TBFα. TBF1 produced in vitro yields protein-DNA complexes with (TTAGGG)(n) probes that have mobilities on native polyacrylamide gels identical to those produced by partially purified TBFα from yeast cells. Furthermore, when extracts are prepared from a strain containing a TBF1 gene with an antigen tag, we find that the antigen copurifies with the predominant (TTAGGG)(n)-binding activity in the extracts. The DNA sequence of TBF1 was determined. The predicted protein sequence suggests that TBF1 may contain a nucleotide-binding domain, but no significant similarities to any other known proteins were identified, nor was an obvious DNA-binding motif apparent. Diploid cells heterozygous for a tbf1::URA3 insertion mutation are viable but upon sporulation give rise to tetrads with only two viable spores, both of which are Ura-, indicating that the TBF1 gene is essential for growth. Possible functions of TBF1 (TFBα) are discussed in light of these new results.
UR - http://www.scopus.com/inward/record.url?scp=0027393752&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0027393752&partnerID=8YFLogxK
U2 - 10.1128/MCB.13.2.1306
DO - 10.1128/MCB.13.2.1306
M3 - Article
C2 - 8423796
AN - SCOPUS:0027393752
VL - 13
SP - 1306
EP - 1314
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
SN - 0270-7306
IS - 2
ER -