This gene encodes ghrelin-obestatin preproprotein, which generates ghrelin and obestatin. Ghrelin is an endogenous ligand for the growth hormone secretagogue receptor and is involved in regulating growth hormone release. Obestatin was initially reported to be an endogenous ligand for the orphan G protein-coupled receptor GPR39 and was involved in satiety and decreased food intake; however, these findings are controversial. Recent reports show that obestatin is involved in inhibiting thirst and anxiety, improving memory, regulating sleep, affecting cell proliferation, and increasing the secretion of pancreatic juice enzymes. Alternative promoters and alternative splicing result in multiple transcript variants, some of which encode different protein isoforms and some of which do not encode a protein but may regulate the ghrelin-obestatin preproprotein expression. In addition, antisense transcripts for this gene have been identified and may also function in regulation of the ghrelin-obestatin preproprotein expression. [provided by RefSeq, Oct 2008].
Function:
Ghrelin is the ligand for growth hormone secretagogue receptor type 1 (GHSR). Induces the release of growth hormone from the pituitary. Has an appetite-stimulating effect, induces adiposity and stimulates gastric acid secretion. Involved in growth regulation.
Obestatin may be the ligand for GPR39. May have an appetite-reducing effect resulting in decreased food intake. May reduce gastric emptying activity and jejunal motility.
Subcellular Location:
Secreted.
Tissue Specificity:
Highest level in stomach. All forms are found in serum as well. Other tissues compensate for the loss of ghrelin synthesis in the stomach following gastrectomy.
Post-translational modifications:
O-octanoylation or O-decanoylation is essential for ghrelin activity. The O-decanoylated forms Ghrelin-27-C10 and Ghrelin-28-C10 differ in the length of the carbon backbone of the carboxylic acid bound to Ser-26. A small fraction of ghrelin, ghrelin-28-C10:1, may be modified with a singly unsaturated carboxylic acid.
Amidation of Leu-98 is essential for obestatin activity.
Similarity:
Belongs to the motilin family.
SWISS:
Q9UBU3
Gene ID:
51738
Database links:
Entrez Gene: 51738 Human
Entrez Gene: 58991 Mouse
Entrez Gene: 59301 Rat
Entrez Gene: 574280 Rhesus monkey
Omim: 605353 Human
SwissProt: Q6BEG6 Cat
SwissProt: Q9BEF8 Dog
SwissProt: Q9UBU3 Human
SwissProt: Q9EQX0 Mouse
SwissProt: Q9GKY5 Pig
SwissProt: Q9QYH7 Rat
Unigene: 590080 Human
Unigene: 672979 Human
Unigene: 379095 Mouse
Unigene: 42103 Rat
Ghrelin是近年来发现的一种内源性生长激素促分泌剂受体的配体(一种新的生长激素释放肽)。
广泛分布在人中枢神经系统(下丘脑、垂体)和消化系统(胃、肠、胰腺),并被发现拥有多种生物功能,如通过下丘脑刺激食欲、增加胃酸分泌、提高胃肠蠕动等.进而ghrelin和GHS-R在不同器官肿瘤组织中被发现,如垂体瘤、胃癌、肠癌、乳腺癌、甲状腺滤泡状癌,Ghrelin蛋白的种属同源性较高,人、大、小鼠、猪、羊、犬、牛都有存在。
大量研究证明ghrelin能影响不同肿瘤细胞的生长与增殖.其广泛的生物活性为今后肿瘤的诊断、治疗及预后的评估提供了新的研究方向.
Picture |
Paraformaldehyde-fixed, paraffin embedded (Rat pancreas); Antigen retrieval by boiling in sodium citrate buffer (pH6.0) for 15min; Block endogenous peroxidase by 3% hydrogen peroxide for 20 minutes; Blocking buffer (normal goat serum) at 37°C for 30min; Antibody incubation with (Ghrelin) Polyclonal Antibody, Unconjugated (SL0467R) at 1:400 overnight at 4°C, followed by operating according to SP Kit(Rabbit) (sp-0023) instructions and DAB staining.
Tissue/cell: rat brain tissue; 4% Paraformaldehyde-fixed and paraffin-embedded;
Antigen retrieval: citrate buffer ( 0.01M, pH 6.0 ), Boiling bathing for 15min; Block endogenous peroxidase by 3% Hydrogen peroxide for 30min; Blocking buffer (normal goat serum,SLC0005) at 37℃ for 20 min;
Incubation: Anti-Ghrelin Polyclonal Antibody, Unconjugated(SL0467R) 1:100, overnight at 4°C, followed by conjugation to the secondary antibody(SP-0023) and DAB(SLC0010) staining
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