Biomaterial Database

Hypoxia affects expression of circadian genes PER1 and CLOCK in mouse brain. 2001

D Chilov, and T Hofer, and C Bauer, and R H Wenger, and M Gassmann

Institutes of Physiology and Veterinary Physiology, University of Zürich, CH-8057 Zürich, Switzerland.

The key elements of circadian clockwork and oxygen homeostasis are the PAS protein family members PER and CLOCK and hypoxia-inducible factor 1alpha (HIF-1alpha). The PAS domain serves as an interface for protein-protein interactions. We asked whether a cross-talk exists between the PAS components of hypoxic and circadian pathways. We found several isoforms of PER1 protein that exhibit tissue-specific size differences. In the mouse brain, a predominantly nuclear 48 kDa isoform that followed a daily rhythm was observed. The 48 kDa form was found in the nuclear fractions derived from mouse liver, Swiss3T3 fibroblasts, and N2A neuroblastoma cells. In mouse kidney and human 293 kidney cells, a 55 kDa PER1 form was detected. CLOCK was observed as a predicted 100 kDa protein in rat-1 cells and in all analyzed mouse tissues including brain, liver, kidney, and spleen. In contrast to PER1, CLOCK protein expression was not rhythmic. Exposure to hypoxia led to increased PER1 and CLOCK protein levels in mice. Based on coimmunoprecipitation experiments that showed protein-protein interaction between PER1 and the alpha subunit of HIF-1, we suggest that these hypoxic effects may be modulated by HIF-1alpha.-Chilov, D., Hofer, T., Bauer, C., Wenger, R. H., Gassmann, M. Hypoxia affects expression of circadian genes PER1 and CLOCK in mouse brain.

UI	MeSH Term	Description	Entries
D008815	Mice, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.	Inbred Mouse Strains,Inbred Strain of Mice,Inbred Strain of Mouse,Inbred Strains of Mice,Mouse, Inbred Strain,Inbred Mouse Strain,Mouse Inbred Strain,Mouse Inbred Strains,Mouse Strain, Inbred,Mouse Strains, Inbred,Strain, Inbred Mouse,Strains, Inbred Mouse
D009687	Nuclear Proteins	Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.	Nucleolar Protein,Nucleolar Proteins,Nuclear Protein,Protein, Nuclear,Protein, Nucleolar,Proteins, Nuclear,Proteins, Nucleolar
D011233	Precipitin Tests	Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.	Precipitin Test,Test, Precipitin,Tests, Precipitin
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006367	HeLa Cells	The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for, among other things, VIRUS CULTIVATION and PRECLINICAL DRUG EVALUATION assays.	Cell, HeLa,Cells, HeLa,HeLa Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man