Download MendeleyAsymmetric dimeric assembly of Suv3 helicase facilitates processive RNA unwinding.
Patra, M., Jain, M., Li, Y.C., Chen, Y.P., Golzarroshan, B., Yuan, H.S.(2026) Nat Commun
- PubMed: 41986356 Search on PubMed
- DOI: https://doi.org/10.1038/s41467-026-71901-2
- Primary Citation Related Structures:
9VC8, 9VCC, 9VCT, 9VCU, 9VCV, 9VCW, 9VD0, 9VD1 - PubMed Abstract:
Human Suv3 is a dimeric helicase that collaborates with the exoribonuclease PNPase to mediate RNA decay and surveillance in mitochondria. Despite its pivotal role in maintaining mitochondrial homeostasis, the molecular mechanism underlying Suv3-mediated RNA unwinding has remained elusive. Here, we present near-atomic-resolution cryogenic electron microscopy structures of Suv3 captured in four functional states: the apo form, two binary complexes with ADP and single-stranded RNA (ssRNA), and a ternary complex with ssRNA and an ATP analog (AMP-PNP). These structures reveal an unexpected asymmetric dimeric organization, in which only one of the two protomers engages in the initial binding of ADP, ssRNA, or both ssRNA and AMP-PNP. Complementary biochemical analyses demonstrate that Suv3 dimerization significantly enhances RNA-binding and unwinding efficiency in an ATP-hydrolysis-dependent manner. Together, these findings provide key insights into the dimeric architecture of Suv3 and establish a mechanistic framework for its coordinated function in processive RNA unwinding.
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC.
Organizational Affiliation:
