RNA Chaperones and the RNA Folding Problem

Daniel Herschlag

doi:10.1074/jbc.270.36.20871

Abstract

RNA Chaperones and the RNA Folding Problem

Highlights

“RNA chaperone” refers to proteins that aid in RNA folding and is not meant to refer to chaperones made of RNA.2 For clarity, the classical chaperones that aid protein folding are referred to as “protein chaperones.” In keeping with the accepted definition of protein chaperones, RNA chaperones are defined as proteins that aid in the process of RNA folding by preventing misfolding or by resolving misfolded species
There are no established examples of RNA chaperones that act in vivo
This hypothesis is presented because the in vitro data reviewed provide support for the hypothesis and this view provides a conceptual framework for RNA folding and RNA/protein interactions

Summary

Folding Problem*

Functional and structural inter-relationships of RNA and proteins in the execution and control of biological processes such as RNA processing, RNA splicing, and translation are increasingly apparent In this minireview, I present an RNA chaperone hypothesis, which fosters the view that constraints imposed by fundamental problems in the folding of RNA have profoundly influenced the nature of RNA/protein interactions in biology. Nonspecific RNA-binding proteins solve the kinetic folding problem in vivo by acting as RNA chaperones that prevent RNA misfolding and resolve misfolded RNAs, thereby ensuring that RNA is accessible for its biological function. In keeping with the accepted definition of protein chaperones, RNA chaperones are defined as proteins that aid in the process of RNA folding by preventing misfolding or by resolving misfolded species This is in contrast to proteins that help protein or RNA folding by catalyzing steps along the folding pathway or by stabilizing the final folded protein or RNA structure.. The kinetic problem in RNA folding is emphasized, while space constraints have greatly limited discussion of the thermodynamic problem

The Two Fundamental Folding Problems of RNA

Out Low

An Evolutionary Perspective

Orchestration of RNA Chaperone Activity in Vivo

RNA Chaperones and the RNA Folding Problem Daniel Herschlag