Abstract:
:Telomeres are specialized structures located at the ends of linear eukaryotic chromosomes that ensure their complete replication and protect them from fusion and degradation. We report here the characterization of the telomeres of the nematode Caenorhabditis elegans. We show that the chromosomes terminate in 4-9 kb of tandem repeats of the sequence TTAGGC. Furthermore, we have isolated clones corresponding to 11 of the 12 C. elegans telomeres. Their subtelomeric sequences are all different from each other, demonstrating that the terminal TTAGGC repeats are sufficient for general chromosomal capping functions. Finally, we demonstrate that the me8 meiotic mutant, which is defective in X chromosome crossing over and segregation, bears a terminal deficiency, that was healed by the addition of telomeric repeats, presumably by the activity of a telomerase enzyme. The 11 cloned telomeres represent an important advance for the completion of the physical map and for the determination of the entire sequence of the C. elegans genome.
journal_name
Proc Natl Acad Sci U S Aauthors
Wicky C,Villeneuve AM,Lauper N,Codourey L,Tobler H,Müller Fdoi
10.1073/pnas.93.17.8983subject
Has Abstractpub_date
1996-08-20 00:00:00pages
8983-8issue
17eissn
0027-8424issn
1091-6490journal_volume
93pub_type
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