Domain

La-type HTH domain (IPR006630)

Short name: La_HTH

Domain relationships

Description

Human Ro ribonucleoproteins (RNPs) are composed of one of the four small Y RNAs and at least two proteins, Ro60 and La. The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome [PMID: 15016896]. In the nucleus, La acts as a RNA polymerase III (RNAP III) transcription factor, while in the cytoplasm, La acts as a translation factor [PMID: 14636586]. In the nucleus, La binds to the 3'UTR of nascent RNAP III transcripts to assist in folding and maturation [PMID: 15004549]. In the cytoplasm, La recognises specific classes of mRNAs that contain a 5'-terminal oligopyrimidine (5'TOP) motif known to control protein synthesis [PMID: 14690589]. The specific recognition is mediated by the N-terminal domain of La, which comprises a La motif and a RNA recognition motif (RRM). The La motif adopts an alpha/beta fold that comprises a winged-helix motif [PMID: 15048103].

Homologous La domain-containing proteins have been identified in a wide range of organisms except Archaea, bacteria and viruses [PMID: 7799435].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles
Pfam
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