A short half-life GFP mouse model for analysis of suprachiasmatic nucleus organization.
Period1 (Per1) is one of several clock genes driving the oscillatory mechanisms that mediate circadian rhythmicity. Per1 mRNA and protein are highly expressed in the suprachiasmatic nuclei, which contain oscillator cells that drive circadian rhythmicity in physiological and behavioral responses. We examined a transgenic mouse in which degradable green fluorescent protein (GFP) is driven by the mPer1 gene promoter. This mouse expresses precise free-running rhythms and characteristic light induced phase shifts. GFP protein (reporting Per1 mRNA) is expressed rhythmically as measured by either fluorescence or immunocytochemistry. In addition the animals show predicted rhythms of Per1 mRNA, PER1 and PER2 proteins. The localization of GFP overlaps with that of Per1 mRNA, PER1 and PER2 proteins. Together, these results suggest that GFP reports rhythmic Per1 expression. A surprising finding is that, at their peak expression time GFP, Per1 mRNA, PER1 and PER2 proteins are absent or not detectable in a subpopulation of SCN cells located in the core region of the nucleus.
LeSauter
Joseph
J
Department of Psychology, Barnard College, 3009 Broadway, New York, NY 10027, USA.
Yan
Lily
L
Vishnubhotla
Bhavana
B
Quintero
Jorge E
JE
Kuhlman
Sandra J
SJ
McMahon
Douglas G
DG
Silver
Rae
R
D000818:Animals; D018797:Cell Cycle Proteins; D002940:Circadian Rhythm / Q000235:genetics; D005786:Gene Expression Regulation; D049452:Green Fluorescent Proteins; D006207:Half-Life; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008027:Light; D008124:Locomotion; D008164:Luminescent Proteins; D051379:Mice; D008822:Mice, Transgenic; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D056950:Period Circadian Proteins; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D013493:Suprachiasmatic Nucleus / Q000378:metabolism*; D014157:Transcription Factors
D018797:Cell Cycle Proteins; D008164:Luminescent Proteins; D009687:Nuclear Proteins; C539023:Per1 protein, mouse; C513312:Per2 protein, mouse; D056950:Period Circadian Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D049452:Green Fluorescent Proteins