한빛사논문
- 조회6,880
Abstract
Xinfu Jiao,1,5 Jeong Ho Chang,2,3,5 Turgay Kilic,2,4 Liang Tong,2,* and Megerditch Kiledjian1,*
1Department Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
2Department Biological Sciences, Columbia University, New York, NY 10027, USA
3Present Address: Department of Biomedical Science, Daegu University, Gyeongsan 712-714, South Korea
4Present Address: Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX 78229, USA
5These authors contributed equally to this work
*Correspondence: Liang Tong, Megerditch Kiledjian
Summary
Recently, we reported that two homologous yeast proteins, Rai1 and Dxo1, function in a quality control mechanism to clear cells of incompletely 5 end-capped messenger RNAs (mRNAs). Here, we report that their mammalian homolog, Dom3Z (referred to as DXO), possesses pyrophosphohydrolase, decapping, and 5-to-3 exoribonuclease activities. Surprisingly, we found that DXO preferentially degrades defectively capped pre-mRNAs in cells. Additional studies show that incompletely capped pre-mRNAs are inefficiently spliced at all introns, a fact that contrasts with current understanding, and are also poorly cleaved for polyadenylation. Crystal structures of DXO in complex with substrate mimic and products at a resolution of up to 1.5Å provide elegant insights into the catalytic mechanism and molecular basis for their three apparently distinct activities. Our data reveal a pre-mRNA 5 end capping quality control mechanism in mammalian cells, indicating DXO as the central player for this mechanism, and demonstrate an unexpected intimate link between proper 5 end capping and subsequent pre-mRNA processing.
논문정보
- Research article
- 2013년 03월 (BRIC 등록일 )
- 국외 연구진
관련 보도자료
- 노컷뉴스
- 2013. 03. 29
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