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The hRPC62 subunit of human RNA polymerase III displays helicase activity.

ABSTRACT: In Eukaryotes, tRNAs, 5S RNA and U6 RNA are transcribed by RNA polymerase (Pol) III. Human Pol III is composed of 17 subunits. Three specific Pol III subunits form a stable ternary subcomplex (RPC62-RPC39-RPC32?/?) being involved in pre-initiation complex formation. No paralogues for subunits of this subcomplex subunits have been found in Pols I or II, but hRPC62 was shown to be structurally related to the general Pol II transcription factor hTFIIE?. Here we show that these structural homologies extend to functional similarities. hRPC62 as well as hTFIIE? possess intrinsic ATP-dependent 3'-5' DNA unwinding activity. The ATPase activities of both proteins are stimulated by single-stranded DNA. Moreover, the eWH domain of hTFIIE? can replace the first eWH (eWH1) domain of hRPC62 in ATPase and DNA unwinding assays. Our results identify intrinsic enzymatic activities in hRPC62 and hTFIIE?.

SUBMITTER: Ayoubi LE

PROVIDER: S-EPMC6821166 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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The hRPC62 subunit of human RNA polymerase III displays helicase activity.

Ayoubi Leyla El LE Dumay-Odelot Hélène H Chernev Aleksandar A Boissier Fanny F Minvielle-Sébastia Lionel L Urlaub Henning H Fribourg Sébastien S Teichmann Martin M

Nucleic acids research 20191101 19

In Eukaryotes, tRNAs, 5S RNA and U6 RNA are transcribed by RNA polymerase (Pol) III. Human Pol III is composed of 17 subunits. Three specific Pol III subunits form a stable ternary subcomplex (RPC62-RPC39-RPC32α/β) being involved in pre-initiation complex formation. No paralogues for subunits of this subcomplex subunits have been found in Pols I or II, but hRPC62 was shown to be structurally related to the general Pol II transcription factor hTFIIEα. Here we show that these structural homologies ...[more]

PMID: 31529052

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