title: Schizothorax davidi ghrelin: cDNA cloning, tissue distribution and indication for its stimulatory character in food intake.
abstract: Ghrelin is a gut/brain hormone with a unique acyl modification and various biological functions in fish and mammals. The objectives of this project were to identify ghrelin gene organization, study tissue specific ghrelin mRNA expression and investigate the short- (0, 0.5, 1.5, 3, 6, 9, 12h post-fasting) and long- (1, 3, 5, 7 days) term fasting as well as refeeding after a 7 day fasting induced changes in the expression of ghrelin mRNA in Schizothorax davidi. Our reverse transcription polymerase chain reaction analysis confirmed the predicted ghrelin sequence available in the GenBank and identified ghrelin mRNA expression in several tissues including the gut, liver, brain, heart, spleen, head kidney, gill and muscle. Quantitative PCR studies indicated that the expression level of ghrelin mRNA presented ascendant trend in short-term fasting group compared to the fed group, but it did not reach the significant level on statistics, while there is a significant increase in ghrelin mRNA expression in the gut of Schizothorax davidi fasted for 3, 5 and 7 days when compared to the expression in ad libitum fed fish. Refeeding after a 7 day fasting caused a significant and dramatic decrease in ghrelin mRNA expression in the gut of Schizothorax davidi. An increase in the expression of ghrelin mRNA during fasting, and its decrease following refeeding suggests an orexigenic role for ghrelin in Schizothorax davidi. Overall, our results provide evidence for a highly conserved structure and biological actions of ghrelin during evolution.
authors.affiliation: Department of aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China.
authors.forename: Chaowei
authors.initials: C
authors.lastname: Zhou
authors.forename: Xingdong
authors.initials: X
authors.lastname: Zhang
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.forename: Rongbin
authors.initials: R
authors.lastname: Wei
authors.forename: Dengyue
authors.initials: D
authors.lastname: Yuan
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.forename: Fangjun
authors.initials: F
authors.lastname: Lin
authors.forename: Hongwei
authors.initials: H
authors.lastname: Wu
authors.forename: Fu
authors.initials: F
authors.lastname: Chen
authors.forename: Shiyong
authors.initials: S
authors.lastname: Yang
authors.forename: Defang
authors.initials: D
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Zhiqiong
authors.initials: Z
authors.lastname: Li
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D003530:Cyprinidae / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics*; D004435:Eating / Q000235:genetics*; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D054439:Ghrelin / Q000235:genetics* / Q000378:metabolism*; D008297:Male; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D014018:Tissue Distribution / Q000235:genetics
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D054439:Ghrelin; D012333:RNA, Messenger
keywords: Base pair; GH; GRLN-LP; Ghrelin; Ghrelin-like peptide; Growth hormone; Long-term fasting; MS-222; ORF; Open reading frame; Schizothorax davidi; Short-term fasting; Tricainemethane sulfonate; bp