Separation of silencing from perinuclear anchoring functions in yeast Ku80, Sir4 and Esc1 proteins.

摘要: In budding yeast, the nuclear periphery forms a subcompartment in which telomeres cluster and SIR proteins concentrate. To identify that mediate chromatin anchorage to envelope, candidates were fused LexA targeted an internal GFP-tagged chromosomal locus. Their ability shift locus from random peripheral subnuclear position was monitored living cells. Using fusions cannot silence, we YKu80 312-aa domain of Sir4 (Sir4PAD) as minimal anchoring elements, each able relocalize periphery. Sir4PAD-mediated tethering requires either Ku complex or Esc1, acidic protein is localized inner face envelope even absence Ku, Nup133. Finally, demonstrate Ku- Esc1-dependent pathways natural telomere vivo. These data provide first unambiguous identification interactions are both necessary sufficient localize envelope.