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Internal ribosomal entry site-mediated translation is important for rhythmic PERIOD1 expression.

ABSTRACT: The mouse PERIOD1 (mPER1) plays an important role in the maintenance of circadian rhythm. Translation of mPer1 is directed by both a cap-dependent process and cap-independent translation mediated by an internal ribosomal entry site (IRES) in the 5' untranslated region (UTR). Here, we compared mPer1 IRES activity with other cellular IRESs. We also found critical region in mPer1 5'UTR for heterogeneous nuclear ribonucleoprotein Q (HNRNPQ) binding. Deletion of HNRNPQ binding region markedly decreased IRES activity and disrupted rhythmicity. A mathematical model also suggests that rhythmic IRES-dependent translation is a key process in mPER1 oscillation. The IRES-mediated translation of mPer1 will help define the post-transcriptional regulation of the core clock genes.

SUBMITTER: Lee KH

PROVIDER: S-EPMC3360671 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Internal ribosomal entry site-mediated translation is important for rhythmic PERIOD1 expression.

Lee Kyung-Ha KH Kim Sung-Hoon SH Kim Do-Yeon DY Kim Seunghwan S Kim Kyong-Tai KT

PloS one 20120525 5

The mouse PERIOD1 (mPER1) plays an important role in the maintenance of circadian rhythm. Translation of mPer1 is directed by both a cap-dependent process and cap-independent translation mediated by an internal ribosomal entry site (IRES) in the 5' untranslated region (UTR). Here, we compared mPer1 IRES activity with other cellular IRESs. We also found critical region in mPer1 5'UTR for heterogeneous nuclear ribonucleoprotein Q (HNRNPQ) binding. Deletion of HNRNPQ binding region markedly decreas ...[more]

PMID: 22662251

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