Format

Send to

Choose Destination
Nat Cell Biol. 2011 Jun 12;13(7):867-74. doi: 10.1038/ncb2263.

The PIAS homologue Siz2 regulates perinuclear telomere position and telomerase activity in budding yeast.

Author information

1
Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.

Abstract

Budding yeast telomeres are reversibly bound at the nuclear envelope through two partially redundant pathways that involve the Sir2/3/4 silencing complex and the Yku70/80 heterodimer. To better understand how this is regulated, we studied the role of SUMOylation in telomere anchoring. We find that the PIAS-like SUMO E3 ligase Siz2 sumoylates both Yku70/80 and Sir4 in vivo and promotes telomere anchoring to the nuclear envelope. Remarkably, loss of Siz2 also provokes telomere extension in a telomerase-dependent manner that is epistatic with loss of the helicase Pif1. Consistent with our previously documented role for telomerase in anchorage, normal telomere anchoring in siz2 Δ is restored by PIF1 deletion. By live-cell imaging of a critically short telomere, we show that telomeres shift away from the nuclear envelope when elongating. We propose that SUMO-dependent association with the nuclear periphery restrains bound telomerase, whereas active elongation correlates with telomere release.

PMID:
21666682
DOI:
10.1038/ncb2263
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center