Given that Hsp90 functionally correlates with Argonaute in higher eukaryotes, we examined the interaction between Hsp90 （Swol） and Agoland the function of Hsp90 on heterochromatic gene silencing in fission yeast Schizosaccharomyces pombe. The results showed that Swol could stabilize Agol through interaction with Agol in fission yeast. The interaction between Swol and Agol depends on N domain and the central region of Swol, as well as the N and PAZ domains of Agol. The centromeric silencing was alleviated in the swol-26 mutant, but the silencing of reporter gene at telomere and rDNA regions remained unchanged. Double mutants of swol-26 dcrlA and swo1-26 agolA showed enhanced silencing defects at centromeric regions. In the mating type region, we observed a significant derepression ofgene silencing in the swol-26 mutant. The artificial RITS complex-dependent silencing system was also defective in the swol-26 mutant. Our results found a new role of lisp90 in gene silencing at heterochromatin regions in S. pombe.%鉴于高等生物中Hsp90与Argonaute蛋白的功能相关性,研究了裂殖酵母中Hsp90/Swo1与Ago1蛋白之间的相互关系以及对异染色质区基因沉默的影响。结果表明,裂殖酵母中Swo1蛋白通过与Ago1蛋白的相互作用,可以稳定Ago1蛋白,并且这种相互作用依赖于Swo1的N端和中央结构域以及Ago1的N端和PAZ结构域。在着丝粒的otr区和imr区,swo1＋基因的突变会引起区域内基因沉默的解除,并且与RNAi组分双突变后（ago1Δ或dcr1Δ）,基因沉默解除的效果加强。在交配型区,swo1＋基因突变后也会引起显著的基因沉默解除现象。当swo1＋基因突变后,依赖于Tas3的人工异染色质区基因沉默解除。研究发现了裂殖酵母中热激蛋白Hsp90的新功能,即参与异染色质区的基因沉默调控。
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