title: PERIOD2 is a circadian negative regulator of PAI-1 gene expression in mice.
abstract: An increased level of obesity-induced plasma plasminogen activator inhibitor-1 (PAI-1) is considered a risk factor for cardiovascular disease. To determine whether the circadian clock component PERIOD2 (PER2) is involved in the regulation of PAI-1 gene expression, we performed transient transfection assays in vitro, and generated transgenic (Tg) mice overexpressing PER2. We then compared PAI-1 expression in Tg and wild-type (WT) mice with or without obesity induced by a high-fat/high-sucrose diet. PER2 suppressed CLOCK:BMAL1- and CLOCK:BMAL2-dependent transactivation of the PAI-1 promoter in vitro. Furthermore, nuclear translocation is dispensable for PER2 to suppress CLOCK:BMAL1-dependent transactivation of the PAI-1 promoter, because functional loss of the nuclear localization domain did not affect either the interaction with BMAL1 or the suppressive role of PER2. The diurnal expression of clock and clock-controlled genes was disrupted in a gene-specific manner, whereas that of PAI-1 mRNA was significantly damped in the hearts of PER2 Tg mice fed with a normal diet. Obesity-induced plasma PAI-1 increase was significantly suppressed in Tg mice in accordance with cardiac PAI-1 mRNA levels, whereas body weight gain and changes in metabolic parameters were identical between WT and Tg mice. Endogenous PAI-1 gene expression induced by transforming growth factor-beta1 was significantly attenuated in embryonic fibroblasts derived from Tg mice compared with those from WT mice. Our results demonstrated that PER2 represses PAI-1 gene transcription in a BMAL1/2-dependent manner. The present findings also suggest that PER2 attenuates obesity-induced hypofibrinolysis by downregulating PAI-1 expression independently of metabolic disorders.
authors.affiliation: Clock Cell Biology Research Group, Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan.
authors.forename: Katsutaka
authors.initials: K
authors.lastname: Oishi
authors.forename: Koyomi
authors.initials: K
authors.lastname: Miyazaki
authors.forename: Daisuke
authors.initials: D
authors.lastname: Uchida
authors.forename: Naoki
authors.initials: N
authors.lastname: Ohkura
authors.forename: Miyuki
authors.initials: M
authors.lastname: Wakabayashi
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Doi
authors.forename: Juzo
authors.initials: J
authors.lastname: Matsuda
authors.forename: Norio
authors.initials: N
authors.lastname: Ishida
mesh_terms: D056930:ARNTL Transcription Factors; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D056926:CLOCK Proteins; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002940:Circadian Rhythm / Q000187:drug effects / Q000235:genetics*; D004041:Dietary Fats / Q000008:administration & dosage / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D051379:Mice; D009206:Myocardium / Q000378:metabolism; D041681:NIH 3T3 Cells; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D056950:Period Circadian Proteins; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D013395:Sucrose / Q000008:administration & dosage / Q000494:pharmacology; D013489:Suppression, Genetic / Q000187:drug effects; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000187:drug effects; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology
chemical_list: D056930:ARNTL Transcription Factors; D051792:Basic Helix-Loop-Helix Proteins; D056926:CLOCK Proteins; D018797:Cell Cycle Proteins; D004041:Dietary Fats; D009687:Nuclear Proteins; D056950:Period Circadian Proteins; D017395:Plasminogen Activator Inhibitor 1; D012333:RNA, Messenger; D013395:Sucrose; D015534:Trans-Activators; D014157:Transcription Factors; D053773:Transforming Growth Factor beta1; C538961:Bmal1 protein, mouse; C431792:Arntl2 protein, mouse; C513312:Per2 protein, mouse; C538944:Clock protein, mouse; C538945:Clock protein, rat