日本群馬大學研究人員日前發(fā)表論文說,,人體內一種特殊蛋白質能促使癌癥惡化,,抑制這種蛋白質發(fā)揮作用,,將成為今后抗癌藥物新的研究方向,。
研究人員在新一期美國《分子細胞》雜志網(wǎng)絡版上發(fā)表論文說,,這種特殊蛋白質名為“Hsp90”,,能加強聚合酶“Polη”的功能,。“Polη”容易使DNA(脫氧核糖核酸)在復制過程中發(fā)生錯誤,從而導致基因變異,。癌細胞的基因如果因“Polη”而反復發(fā)生變異,,將導致癌癥惡化,還會導致癌細胞對放化療的耐受性增強,。
研究人員發(fā)現(xiàn),,如果使用藥劑讓“Hsp90”無法發(fā)揮作用,“Polη”就會被分解或者失效,,癌癥惡化速度就會明顯放緩,。
參與這項研究的群馬大學教授山下孝之說,以前的癌癥治療都是抑制癌細胞本身的增殖,,這次的發(fā)現(xiàn)將使抑制蛋白質“Hsp90”成為主攻方向,。(生物谷Bioon.com)
生物谷推薦原始出處:
Molecular Cell, Volume 37, Issue 1, 79-89, 15 January 2010
The Molecular Chaperone Hsp90 Regulates Accumulation of DNA Polymerase η at Replication Stalling Sites in UV-Irradiated Cells
Takayuki Sekimoto, Tsukasa Oda, Franklin Mayca Pozo, Yoshiki Murakumo, Chikahide Masutani, Fumio Hanaoka, Takayuki Yamashita
DNA polymerase η (Pol η) is a member of the mammalian Y family polymerases and performs error-free translesion synthesis across UV-damaged DNA. For this function, Pol η accumulates in nuclear foci at replication stalling sites via its interaction with monoubiquitinated PCNA. However, little is known about the posttranslational control mechanisms of Pol η, which regulate its accumulation in replication foci. Here, we report that the molecular chaperone Hsp90 promotes UV irradiation-induced nuclear focus formation of Pol η through control of its stability and binding to monoubiquitinated PCNA. Our data indicate that Hsp90 facilitates the folding of Pol η into an active form in which PCNA- and ubiquitin-binding regions are functional. Furthermore, Hsp90 inhibition potentiates UV-induced cytotoxicity and mutagenesis in a Pol η-dependent manner. Our studies identify Hsp90 as an essential regulator of Pol η-mediated translesion synthesis.