西亞試劑優(yōu)勢供應(yīng)上萬種化學(xué)試劑產(chǎn)品,歡迎各位新老客戶咨詢、選購!

登錄

¥0.00

聯(lián)系方式:400-990-3999 / 郵箱:sales@xiyashiji.com

西亞試劑 —— 品質(zhì)可靠,值得信賴

西亞試劑:Splicing proofreading at 5′ splice sites by ATPase Prp28p

Splicing proofreading at 5′ splice sites by ATPase Prp28p

Fei Yang,Xiu-Ye Wang,Zhi-Min Zhang,Jia Pu,Yu-Jie Fan,Jiahai Zhou,Charles C. Query and Yong-Zhen Xu

Fidelity and efficiency of pre-mRNA splicing are critical for generating functional mRNAs, but how such accuracy in 5′ splice site (SS) selection is attained is not fully clear. Through a series of yeast genetic screens, we isolated alleles of prp28 that improve splicing of suboptimal 5′SS substrates, demonstrating that WT-Prp28p proofreads, and consequently rejects, poor 5′SS. Prp28p is thought to facilitate the disruption of 5′SS–U1 snRNA pairing to allow for 5′SS–U6 snRNA pairing in the catalytic spliceosome; unexpectedly, 5′SS proofreading by Prp28p is dependent on competition with the stability of the 5′SS:U6 duplex, but not the 5′SS:U1 duplex. E404K, the strongest prp28 allele containing a mutation located in the linker region between adenosine triphosphatase (ATPase) subdomains, exhibited lower RNA-binding activity and enhanced splicing of suboptimal substrates before first-step catalysis, suggesting that decreased Prp28p activity allows longer time for suboptimal 5′SS substrates to pair with U6 snRNA and thereby reduces splicing fidelity. Residue E404 is critical for providing high splicing activity, demonstrated here in both yeast and Drosophila cells. Thus, the subdomain linker in Prp28p plays important roles both in splicing efficiency across species and in proofreading of 5′SS.