Chaperones, Molecular

Abstract

Some proteins in the cell are needed to help other proteins reach their final active conformations: these are referred to as molecular chaperones. Molecular chaperones can be grouped into families by sequence similarity, and they act through a variety of mechanisms. They are found in all cell types and in most locations within the cell. Many are induced by stresses such as heat shock. This chapter will review the reasons why molecular chaperones are required in the cell, and then discuss each of the major families of molecular chaperones in turn, in terms of structure, mechanism of action, and cellular role. Most molecular chaperones act in networks with other chaperones, and some of these will be reviewed. Many molecular chaperones interact with a broad range of different substrates, but some are specific to particular proteins, and examples of these will be discussed.