Discovery and characterization of novel RNA repair systems
type: CreativeWork
description: RNA is one of the major macromolecules essential for all known forms of life. RNA in the cell is subject to many types of damage as DNA, and the ubiquitous RNA degradation by surveillance machinery is an important way to respond RNA damage. However, RNA repair is an alternative way for cells to deal with RNA damage, which may play an important role in maintenance of cellular RNAs and even for cell survival. RNA repair is the mechanism that rectifies the purposeful RNA damage during RNA processing or cellular stress. To counter the unexpected RNA breakage, RNA repair systems have evolved in some organisms to restore the normal structure and function of RNA. The first RNA repair system was found in T4phage, in which two proteins T4Pnkp and T4Rnl carried out RNA healing and sealing, respectively. The bacterial Pnkp/Hen1 complex has also been shown to repair ribotoxin-cleaved RNAs in vitro, but it was distinguished from T4 systems by performing 3’-terminal 2’-O-methylation during RNA repair, which prevents the repaired RNA from repeated cleavage at the same site. Bacterial Pnkp and Hen1 appear pair-wise in the same operon in approximately 5% of known bacterial species. Although the bacterial Pnkp has been shown to possess kinase, phosphatase for RNA healing and all the signature motifs of a RNA ligase, it alone is not able to carry out RNA repair. In our study, we crystallized an active RNA ligase consisting of the C-terminal half of Pnkp (Pnkp-C) and the N-terminal half of Hen1 (Hen1-N) from Clostridium thermocellum, and provided the molecular basis for the ligase activation of bacterial Pnkp by Hen1. We also carried out a detailed functional study to pinpoint the activation step during RNA ligation. Guided by the sequence and structure, we created a series of point mutants for this new ligase and carried out biochemical assays. These studies provide additional insight into the mechanism of RNA ligation by Pnkp/Hen1. Based on a comprehensive Blast search, a novel RNA r…
abstract: RNA is one of the major macromolecules essential for all known forms of life. RNA in the cell is subject to many types of damage as DNA, and the ubiquitous RNA degradation by surveillance machinery is an important way to respond RNA damage. However, RNA repair is an alternative way for cells to deal with RNA damage, which may play an important role in maintenance of cellular RNAs and even for cell survival. RNA repair is the mechanism that rectifies the purposeful RNA damage during RNA processing or cellular stress. To counter the unexpected RNA breakage, RNA repair systems have evolved in some organisms to restore the normal structure and function of RNA. The first RNA repair system was found in T4phage, in which two proteins T4Pnkp and T4Rnl carried out RNA healing and sealing, respectively. The bacterial Pnkp/Hen1 complex has also been shown to repair ribotoxin-cleaved RNAs in vitro, but it was distinguished from T4 systems by performing 3’-terminal 2’-O-methylation during RNA repair, which prevents the repaired RNA from repeated cleavage at the same site. Bacterial Pnkp and Hen1 appear pair-wise in the same operon in approximately 5% of known bacterial species. Although the bacterial Pnkp has been shown to possess kinase, phosphatase for RNA healing and all the signature motifs of a RNA ligase, it alone is not able to carry out RNA repair. In our study, we crystallized an active RNA ligase consisting of the C-terminal half of Pnkp (Pnkp-C) and the N-terminal half of Hen1 (Hen1-N) from Clostridium thermocellum, and provided the molecular basis for the ligase activation of bacterial Pnkp by Hen1. We also carried out a detailed functional study to pinpoint the activation step during RNA ligation. Guided by the sequence and structure, we created a series of point mutants for this new ligase and carried out biochemical assays. These studies provide additional insight into the mechanism of RNA ligation by Pnkp/Hen1. Based on a comprehensive Blast search, a novel RNA r…
author: Wang, Pei
keywords: structural biology, Phosphatase, Kinase, Hen1, RNA ligase, ribotoxin, RNA damage, RNA repair
date published: 2015-07-22T22:32:45Z
date modified: 2026-07-22T22:26:12Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/78582