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Detection of dsRNA-binding domains in RNA helicase A and Drosophila maleless: implications for monomeric RNA helicases.

ABSTRACT: Searches with dsRNA-binding domain profiles detected two copies of the domain in each of RNA helicase A, Drosophila maleless and C. elegans ORF T20G5-11 (of unknown function). RNA helicase A is unusual in being one of the few characterised DEAD/DExH helicases that are active as monomers. Other monomeric DEAD/DExH RNA helicases (p68, NPH-II) have domains that match another RNA-binding motif, the RGG repeat. The DEAD/DExH domain appears to be insufficient on its own to promote helicase activity and additional RNA-binding capacity must be supplied either as domains adjacent to the DEAD/DExH-box or by bound partners as in the eIF-4AB dimer. The presence or absence of extra RNA-binding domains should allow classification of DEAD/DExH proteins as monomeric or multimeric helicases.

SUBMITTER: Gibson TJ

PROVIDER: S-EPMC308209 | biostudies-other | 1994 Jul

REPOSITORIES: biostudies-other

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Detection of dsRNA-binding domains in RNA helicase A and Drosophila maleless: implications for monomeric RNA helicases.

Gibson T J TJ Thompson J D JD

Nucleic acids research 19940701 13

Searches with dsRNA-binding domain profiles detected two copies of the domain in each of RNA helicase A, Drosophila maleless and C. elegans ORF T20G5-11 (of unknown function). RNA helicase A is unusual in being one of the few characterised DEAD/DExH helicases that are active as monomers. Other monomeric DEAD/DExH RNA helicases (p68, NPH-II) have domains that match another RNA-binding motif, the RGG repeat. The DEAD/DExH domain appears to be insufficient on its own to promote helicase activity an ...[more]

PMID: 8041617

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