A conserved double-stranded RNA-binding domain.

TLDR

Similar dsRNA‑binding domains are found in multiple proteins such as human DAI, TAR‑binding protein, and bacterial RNase III. The authors analyzed staufen and Xlrbpa domains to delineate the minimal region that binds dsRNA. A conserved 65‑ to 68‑amino‑acid dsRNA‑binding domain was identified in Drosophila staufen and Xenopus Xlrbpa, and its consensus sequence aligns with other known dsRNA‑binding domains.

Abstract

We have identified a double-stranded (ds)RNA-binding domain in each of two proteins: the product of the Drosophila gene staufen, which is required for the localization of maternal mRNAs, and a protein of unknown function, Xlrbpa, from Xenopus. The amino acid sequences of the binding domains are similar to each other and to additional domains in each protein. Database searches identified similar domains in several other proteins known or thought to bind dsRNA, including human dsRNA-activated inhibitor (DAI), human trans-activating region (TAR)-binding protein, and Escherichia coli RNase III. By analyzing in detail one domain in staufen and one in Xlrbpa, we delimited the minimal region that binds dsRNA. On the basis of the binding studies and computer analysis, we have derived a consensus sequence that defines a 65- to 68-amino acid dsRNA-binding domain.