TY - JOUR
T1 - ST-1, a 39-kilodalton protein in Trypanosoma brucei, exhibits a dual affinity for the duplex form of the 29-base-pair subtelomeric repeat and its C-rich strand
AU - Eid, Josiane E.
AU - Sollner-Webb, Barbara
PY - 1995/1
Y1 - 1995/1
N2 - In our attempt to identify telomere region-binding proteins in Trypanosoma brucei, we identified ST-1, a polypeptide with novel features. ST-1 was chromatographically purified from S-100 cell extracts and was renatured from a sodium dodecyl sulfate-protein gel as a 39-kDa polypeptide. It forms a specific complex with the trypanosome telomere repeats of TTAGGG, but more significantly, it shows a higher affinity for the 29-bp subtelomere repeats of T. brucei, These 29-mer boxes are a large tandem series of telomere- derived repeats which separate the simple telomere DNA from middle-repetitive telomere-associated sequences on many chromosomes. ST-1 is the first example of a protein binding within such large repetitive subtelomere elements in trypanosomes or other organisms. ST-1 is also novel in that it has a selective affinity for the C-rich strands of both the subtelomeric 29-mer and the telomere repeats, comparable to that for the duplex form of the respective repeats. All previously described telomere-binding proteins have affinity for only the duplex form or for the G-rich strand. This C-rich strand binding specificity of ST-1 may provide insight into this protein's mechanism of binding in vivo.
AB - In our attempt to identify telomere region-binding proteins in Trypanosoma brucei, we identified ST-1, a polypeptide with novel features. ST-1 was chromatographically purified from S-100 cell extracts and was renatured from a sodium dodecyl sulfate-protein gel as a 39-kDa polypeptide. It forms a specific complex with the trypanosome telomere repeats of TTAGGG, but more significantly, it shows a higher affinity for the 29-bp subtelomere repeats of T. brucei, These 29-mer boxes are a large tandem series of telomere- derived repeats which separate the simple telomere DNA from middle-repetitive telomere-associated sequences on many chromosomes. ST-1 is the first example of a protein binding within such large repetitive subtelomere elements in trypanosomes or other organisms. ST-1 is also novel in that it has a selective affinity for the C-rich strands of both the subtelomeric 29-mer and the telomere repeats, comparable to that for the duplex form of the respective repeats. All previously described telomere-binding proteins have affinity for only the duplex form or for the G-rich strand. This C-rich strand binding specificity of ST-1 may provide insight into this protein's mechanism of binding in vivo.
UR - http://www.scopus.com/inward/record.url?scp=0028988486&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028988486&partnerID=8YFLogxK
U2 - 10.1128/MCB.15.1.389
DO - 10.1128/MCB.15.1.389
M3 - Article
C2 - 7799947
AN - SCOPUS:0028988486
SN - 0270-7306
VL - 15
SP - 389
EP - 397
JO - Molecular and cellular biology
JF - Molecular and cellular biology
IS - 1
ER -