Abstract:
:Telomerase is an RNA-directed DNA polymerase, composed of RNA and protein subunits, that replicates the telomere ends of linear eukaryotic chromosomes. Using a genetic strategy described here, we identify the product of the EST2 gene, Est2p, as a subunit of telomerase in the yeast Saccharomyces cerevisiae. Est2p is required for enzyme catalysis, as mutations in EST2 were found to result in the absence of telomerase activity. Immunochemical experiments show that Est2p is an integral subunit of the telomerase enzyme. Critical catalytic residues present in RNA-directed DNA polymerases are conserved in Est2p; mutation of one such residue abolishes telomerase activity, suggesting a direct catalytic role for Est2p.
journal_name
Proc Natl Acad Sci U S Aauthors
Counter CM,Meyerson M,Eaton EN,Weinberg RAdoi
10.1073/pnas.94.17.9202subject
Has Abstractpub_date
1997-08-19 00:00:00pages
9202-7issue
17eissn
0027-8424issn
1091-6490journal_volume
94pub_type
杂志文章abstract::Citrus bacterial canker (CBC) caused by Xanthomonas axonopodis pv. citri (Xac) was first documented in India and Java in the mid 19th century. Since that time, the known distribution of the disease has steadily increased. Concurrent with the dispersion of the pathogen, the diversity of described strains continues to i...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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