TEL12L Summary Help

Systematic Name TEL12L
Feature Type telomere
Description Telomeric region on the left arm of Chromosome XII; composed of an X element core sequence, X element combinatorial repeats, and three distinct regions of telomeric repeats separated by two short Y' elements (1, 2 and see Summary Paragraph)
Chromosomal Location
ChrXII:12085 to 1 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Genetic position: -33 cM
sequence information
ChrXII:12085 to 1 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
This feature contains embedded feature(s): YLL065W | YLL066C | YLL067C | YLL066W-A | YLL066W-B | YLL067W-A | TEL12L-TR1 | TEL12L-TR2 | TEL12L-TR3 | TEL12L-XC | TEL12L-XR | TEL12L-YP1 | TEL12L-YP2
Genetic position: -33 cM
Last Update Coordinates: 2003-09-09 | Sequence: 2003-09-09
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
External Links All Associated Seq | Search all NCBI (Entrez)
Primary SGDIDS000028910

The chromosome ends of Saccharomyces cerevisiae are complex mosaics of several different types of telomeric and subtelomeric elements known as X element core sequences, X element combinatorial repeats, telomeric repeats, and Y' elements (2). The X element core sequence, a small conserved element of ~475 bp containing an ARS sequence and in most cases an Abf1p binding site, is the only region shared by all chromosome ends (2, 1). The X element combinatorial repeats, formerly known as subtelomeric repeats or STRs, are located between the X element core sequence and the telomeric end and are usually present as a combination of one or more of several types of smaller elements designated D, C, B, or A (2, 1). The telomeric repeat is a G-rich terminal sequence of the form (TG1-3)n that is maintained by telomerase (1). The Y' element is a helicase-encoding repetitive sequence found in many but not all subtelomeric regions next to the telomeric repeats, or adjacent X element combinatorial repeats, either as a single copy or tandem repeat of two to four copies (3, 1, 4). Possible functions of telomeric regions include roles in chromosomal segregation, maintenance of chromosome stability, recombinational sequestering, or as a barrier to transcriptional silencing (2, 1).

One of the most complex of all telomeres, TEL12L, the left telomeric region of chromosome XII, is composed of an X element core sequence TEL12L-XC containing an ARS consensus sequence, an Abf1p binding site and a dubious ORF YLL065W, X element combinatorial repeats TEL12L-XR of the D, C, B and A types containing Tbf1p binding sites, followed by the first of three regions of telomeric repeats TEL12L-TR3, the first of two short Y' (Y'-S) elements TEL12L-YP2 containing an ARS consensus sequence, a region of 36-bp repeats, an uncharacterized ORF YLL066C and a dubious ORF YLL066W-A, the second region of telomeric repeats TEL12L-TR2 spanning an uncharacterized ORF YLL066W-B, the second short Y' element TEL12L-YP1 containing an ARS consensus sequence, a region of 36-bp repeats, an uncharacterized ORF YLL067C and a dubious ORF YLL067W-A, and a short terminal stretch of telomeric repeats TEL12L-TR1.

Click on the following figure for more details:

telomere map

Further information can be found at the website of Dr. Ed Louis, Institute of Genetics, The University of Nottingham.

Last updated: 2003-10-29 Contact SGD

References cited on this page View Complete Literature Guide for TEL12L
1) Louis EJ  (1995) The chromosome ends of Saccharomyces cerevisiae. Yeast 11(16):1553-73
2) Louis EJ, et al.  (1994) The chromosome end in yeast: its mosaic nature and influence on recombinational dynamics. Genetics 136(3):789-802
3) Louis EJ and Haber JE  (1992) The structure and evolution of subtelomeric Y' repeats in Saccharomyces cerevisiae. Genetics 131(3):559-74
4) Yamada M, et al.  (1998) Y'-Help1, a DNA helicase encoded by the yeast subtelomeric Y' element, is induced in survivors defective for telomerase. J Biol Chem 273(50):33360-6