期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2017
卷号：114
期号：42
页码：E8855-E8864
DOI：10.1073/pnas.1706611114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We previously created two PER2::LUCIFERASE (PER2::LUC) circadian reporter knockin mice that differ only in the Per2 3′-UTR region: Per2::Luc , which retains the endogenous Per2 3′-UTR and Per2::LucSV , where the endogenous Per2 3′-UTR was replaced by an SV40 late poly(A) signal. To delineate the in vivo functions of Per2 3′-UTR, we analyzed circadian rhythms of Per2::LucSV mice. Interestingly, Per2::LucSV mice displayed more than threefold stronger amplitude in bioluminescence rhythms than Per2::Luc mice, and also exhibited lengthened free-running periods (∼24.0 h), greater phase delays following light pulse, and enhanced temperature compensation relative to Per2::Luc . Analysis of the Per2 3′-UTR sequence revealed that miR-24, and to a lesser degree miR-30, suppressed PER2 protein translation, and the reversal of this inhibition in Per2::LucSV augmented PER2::LUC protein level and oscillatory amplitude. Interestingly, Bmal1 mRNA and protein oscillatory amplitude as well as CRY1 protein oscillation were increased in Per2::LucSV mice, suggesting rhythmic overexpression of PER2 enhances expression of Per2 and other core clock genes. Together, these studies provide important mechanistic insights into the regulatory roles of Per2 3′-UTR, miR-24, and PER2 in Per2 expression and core clock function.
