Intrinsically Disordered Proteins: the New Sequence-Structure-Function Relations

Intrinsically disordered proteins (IDPs) are a new class of proteins which lack a unique tertiary structure under native conditions while possessing essential biological functions. They take part in various physiological processes such as signal transduction, transcription and translation regulation, and protein modification. The discovery of IDPs challenges the conventional protein "sequence-structure-function" paradigm. In this review, we first overview the history of the conventional protein paradigm and the discovery of IDPs. Then we discuss the characteristics of IDPs in terms of sequence, structure, and biological function. Taking molecular recognition processes as an example, we further introduce current opinions on the advantages of IDPs in binding. Finally, we analyze possible applications of the study of IDPs such as further understanding the protein folding mechanism, improving protein structure determination, providing new clues for protein design and new targets for drug design. The current status of IDPs study in China is also briefly presented.