TEL09L-Yp, the long Y' (Y'-L) element on the left arm of chromosome IX, contains an ARS consensus sequence, a region of 36-bp repeats, one uncharacterized ORF YIL177C, and one dubious ORF YIL177W-A.

The Y' element is a 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 (2, 3). Two main types of Y' elements are known, Y'-L and Y'-S, and any particular array will consist of only one type, not a combination of both (1). Y' elements contain helicase-encoding ORFs which are expressed only during meiosis and in telomerase-deficient cells (1). Possible functions include rescue of telomeres when the telomeric repeats are no longer present and a role in telomere maintenance during meiosis (1).

Other features of TEL09L, the left telomeric region of chromosome IX, include an X element core sequence TEL09L-XC, a region of X element combinatorial repeats TEL09L-XR, and a short terminal stretch of telomeric repeats TEL09L-TR.

Click on the following figure for more details:

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

Last updated: 2003-11-18