title: Identification of bovine hibernation-specific protein complex and evidence of its regulation in fasting and aging.
abstract: Hibernation-specific protein (HP) is a plasma protein that regulates hibernation in chipmunks. The HP complex (HP20c) consists of three homologous proteins, HP20, HP25 and HP27, all produced by liver and belonging to the C1q family. To date, HP20c has not been identified in any mammalian species except chipmunk and ground squirrel hibernators. Here, we report a bovine HP20 gene isolated from liver tissue and aortic endothelial cells. Total homology between bovine and chipmunk variants was 63% at the amino acid level. Gene expression was highest in the liver. Western blot revealed HP20 protein in foetal, newborn, calf and adult serum, with highest concentrations in the adult. Similar proteins were detected in sera of other ruminants but not in humans, bears, mice or rats. Bovine HP20 protein was found mainly in ovaries, stomach, heart, kidneys, lungs, testes and prostate, but not in the skeletal muscle. Native HP20 was purified from bovine adult serum as a complex containing 25 and 27 kDa proteins. Mass spectrometry revealed that these proteins are orthologues of chipmunk HP25 and HP27, respectively. Interestingly, bovine HP20 was highly expressed in cattle serum after fasting. Native bovine HP20c may be a useful tool for investigating HP function.
authors: Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.
authors: Satoshi
authors: S
authors: Fujita
authors: Ryuji
authors: R
authors: Okamoto
authors: Masaya
authors: M
authors: Taniguchi
authors: Tomomi
authors: T
authors: Ban-Tokuda
authors: Katsuhisa
authors: K
authors: Konishi
authors: Itaru
authors: I
authors: Goto
authors: Yasunari
authors: Y
authors: Yamamoto
authors: Kazushi
authors: K
authors: Sugimoto
authors: Nobuhiko
authors: N
authors: Takamatsu
authors: Mashio
authors: M
authors: Nakamura
authors: Katsuya
authors: K
authors: Shiraki
authors: Christa
authors: C
authors: Buechler
authors: Masaaki
authors: M
authors: Ito
mesh_terms: D052242:Adiponectin / Q000378:metabolism; D000375:Aging / Q000502:physiology; D000818:Animals; D015153:Blotting, Western; D002417:Cattle; D002478:Cells, Cultured; D005215:Fasting / Q000097:blood; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism*; D006321:Heart; D006605:Hibernation / Q000235:genetics / Q000502:physiology*; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008297:Male; D051379:Mice; D011467:Prostate / Q000378:metabolism; D051381:Rats; D053719:Tandem Mass Spectrometry; D013737:Testis / Q000378:metabolism
chemical_list: D052242:Adiponectin; D006023:Glycoproteins; C115605:hibernation-related protein, vertebrate