Protein Domain : Cold-shock (CSD) domain IPR019844

Type	Domain
Description	The cold-shock domain (CSD) is an ancient β-barrel fold of about 70 aminoacids that binds single-stranded nucleic acids (both RNA and DNA). CSD- containing proteins have been found in all three domains of life and functionin a variety of processes that are related, for the most part, to post- translational gene regulation. CSDs were first found in bacterial cold-shockproteins (CSPs). CSPs are small, abundant proteins that are essentially composed of one CSD. Some members of this family are strongly induced aftercold shock and are involved in adaptation to low temperatures, while others function during normal growth conditions. Bacterial CSPs bind to single-stranded nucleic acids and function as RNA chaperones, rescuing RNAs trapped in unproductive folding states. This general molecular function enables CSPsto participate in the regulation of practically any step of gene expression involving RNA, including transcription, translation, and RNA turnover. Sincetheir discovery in bacterial CSPs, CSDs have been found in many other bacterial and eukaryotic proteins. In multicellular organisms, CSDs areusually embedded in larger proteins [ , , , , ].The CSD adopts a five-stranded antiparallel β-barrel structure, which is similar to the oligonucleotide/oligosaccharide fold (OB-fold). Many CSDs contain the motifs [YF]-G-F-I and [VF]-[VF]-H, which are known as the ribonucleoprotein (RNP)-1 and RNP-2 motifs and include mostof the residues involved in the interaction with nucleic acids. RNP-1 and RNP-2 are located in strands beta2 and beta3, respectively [, , , ].This conserved region is located at the N-terminal. The beginning of this region is highly similar to the RNP-1 RNA-binding motif [ ].
Short Name	CSD_1