National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
P41GM103832
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01GM079429
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
S10OD021600
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01GM122960
米国
引用
ジャーナル: Mol Cell / 年: 2020 タイトル: Cryo-EM Structures of Human Drosha and DGCR8 in Complex with Primary MicroRNA. 著者: Alexander C Partin / Kaiming Zhang / Byung-Cheon Jeong / Emily Herrell / Shanshan Li / Wah Chiu / Yunsun Nam / 要旨: Metazoan microRNAs require specific maturation steps initiated by Microprocessor, comprising Drosha and DGCR8. Lack of structural information for the assembled complex has hindered an understanding ...Metazoan microRNAs require specific maturation steps initiated by Microprocessor, comprising Drosha and DGCR8. Lack of structural information for the assembled complex has hindered an understanding of how Microprocessor recognizes primary microRNA transcripts (pri-miRNAs). Here we present a cryoelectron microscopy structure of human Microprocessor with a pri-miRNA docked in the active site, poised for cleavage. The basal junction is recognized by a four-way intramolecular junction in Drosha, triggered by the Belt and Wedge regions that clamp over the ssRNA. The belt is important for efficiency and accuracy of pri-miRNA processing. Two dsRBDs form a molecular ruler to measure the stem length between the two dsRNA-ssRNA junctions. The specific organization of the dsRBDs near the apical junction is independent of Drosha core domains, as observed in a second structure in the partially docked state. Collectively, we derive a molecular model to explain how Microprocessor recognizes a pri-miRNA and accurately identifies the cleavage site.