Linked Life Data

10215159

Source:http://linkedlifedata.com/resource/pubmed/id/10215159

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-6-10
pubmed:abstractText
The hypothalamic suprachiasmatic nucleus is the site of an endogenous circadian clock synchronized by daily light-dark cycles. At some daily phases, light exposure both shifts the clock and alters the expression of several immediate-early genes in cells of the suprachiasmatic nucleus. We have studied both spontaneous circadian and light-induced expression of several immediate-early gene messenger RNAs and proteins in hamsters in constant darkness or in response to brief light exposure. There was no detectable spontaneous expression of NGFI-A messenger RNA in suprachiasmatic nucleus cells at any circadian phase, but light pulses induced its expression selectively during the subjective night, with highest levels of expression 6 h into the night. We also found that there are two independent rhythms of expression of junB messenger RNA and JunB protein, as well as c-fos messenger RNA and c-Fos protein, in the suprachiasmatic nucleus of hamsters: a rhythm of photic sensitivity expressed throughout the night and a spontaneous rhythm of expression triggered around dawn. Induction of NGFI-A messenger RNA and c-fos messenger RNA and c-Fos protein in response to a light pulse were found throughout the suprachiasmatic nucleus, with the highest levels of expression in the ventrolateral subdivision; however, the spontaneous expression of JunB and c-Fos proteins was confined mainly to the dorsomedial suprachiasmatic nucleus. The temporal and anatomical differences in the expression of these immediate-early genes in the mammalian suprachiasmatic nucleus suggest that their protein products may be involved in different signaling mechanisms mediating either photic entrainment or endogenous oscillations within distinct subpopulations of suprachiasmatic nucleus cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0306-4522
pubmed:author
pubmed:issnType
Print
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
555-71
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10215159-Animals, pubmed-meshheading:10215159-Base Sequence, pubmed-meshheading:10215159-Circadian Rhythm, pubmed-meshheading:10215159-Cricetinae, pubmed-meshheading:10215159-DNA Primers, pubmed-meshheading:10215159-DNA-Binding Proteins, pubmed-meshheading:10215159-Darkness, pubmed-meshheading:10215159-Gene Expression Regulation, pubmed-meshheading:10215159-Genes, Immediate-Early, pubmed-meshheading:10215159-Genes, fos, pubmed-meshheading:10215159-Immediate-Early Proteins, pubmed-meshheading:10215159-Light, pubmed-meshheading:10215159-Male, pubmed-meshheading:10215159-Mesocricetus, pubmed-meshheading:10215159-Molecular Sequence Data, pubmed-meshheading:10215159-Photic Stimulation, pubmed-meshheading:10215159-Photoperiod, pubmed-meshheading:10215159-Protein Biosynthesis, pubmed-meshheading:10215159-Proto-Oncogene Proteins c-fos, pubmed-meshheading:10215159-RNA, Messenger, pubmed-meshheading:10215159-Suprachiasmatic Nucleus, pubmed-meshheading:10215159-Transcription, Genetic, pubmed-meshheading:10215159-Transcription Factors
pubmed:year
1999
pubmed:articleTitle
Circadian and photic regulation of immediate-early gene expression in the hamster suprachiasmatic nucleus.
pubmed:affiliation
Department of Psychology, Dalhousie University, Halifax, Nova Scotia, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't