GHRL

This gene encodes the ghrelin-obestatin preproprotein that is cleaved to yield two peptides, ghrelin and obestatin. Ghrelin is a powerful appetite stimulant and plays an important role in energy homeostasis. Its secretion is initiated when the stomach is empty, whereupon it binds to the growth hormone secretagogue receptor in the hypothalamus which results in the secretion of growth hormone (somatotropin). Ghrelin is thought to regulate multiple activities, including hunger, reward perception via the mesolimbic pathway, gastric acid secretion, gastrointestinal motility, and pancreatic glucose-stimulated insulin secretion. It was initially proposed that obestatin plays an opposing role to ghrelin by promoting satiety and thus decreasing food intake, but this action is still debated. Recent reports suggest multiple metabolic roles for obestatin, including regulating adipocyte function and glucose metabolism. Alternative splicing results in multiple transcript variants. In addition, antisense transcripts for this gene have been identified and may potentially regulate ghrelin-obestatin preproprotein expression. [provided by RefSeq, Nov 2014]

Ghrelin And Obestatin Prepropeptide

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 (By similarity).

Actin polymerization or depolymerization Source: UniProtKB
Activation of MAPK activity Source: UniProtKB
Adult feeding behavior Source: HGNC-UCL
Cartilage development Source: UniProtKB
Cortisol secretion Source: UniProtKB
Decidualization Source: UniProtKB
Dendrite development Source: MGI
Excitatory postsynaptic potential Source: Ensembl
Gastric acid secretion Source: GO_Central
Gastric emptying Source: Ensembl
Glucose metabolic process Source: UniProtKB
G protein-coupled receptor signaling pathway Source: UniProtKB
Growth hormone secretion Source: HGNC-UCL
Hormone-mediated signaling pathway Source: HGNC-UCL
Negative regulation of angiogenesis Source: UniProtKB
Negative regulation of apoptotic process Source: UniProtKB
Negative regulation of circadian sleep/wake cycle, REM sleep Source: BHF-UCL
Negative regulation of endothelial cell proliferation Source: UniProtKB
Negative regulation of inflammatory response Source: UniProtKB
Negative regulation of insulin secretion Source: Ensembl
Negative regulation of interleukin-1 beta production Source: UniProtKB
Negative regulation of interleukin-6 production Source: UniProtKB
Negative regulation of locomotion Source: Ensembl
Negative regulation of tumor necrosis factor production Source: UniProtKB
Positive regulation of adipose tissue development Source: Ensembl
Positive regulation of appetite Source: HGNC-UCL
Positive regulation of bone development Source: Ensembl
Positive regulation of circadian sleep/wake cycle, non-REM sleep Source: BHF-UCL
Positive regulation of cold-induced thermogenesis Source: YuBioLab
Positive regulation of corticotropin secretion Source: BHF-UCL
Positive regulation of cortisol secretion Source: BHF-UCL
Positive regulation of cytosolic calcium ion concentration Source: UniProtKB
Positive regulation of eating behavior Source: Ensembl
Positive regulation of gastric mucosal blood circulation Source: Ensembl
Positive regulation of growth hormone receptor signaling pathway Source: BHF-UCL
Positive regulation of growth hormone secretion Source: BHF-UCL
Positive regulation of growth rate Source: Ensembl
Positive regulation of insulin secretion Source: UniProtKB
Positive regulation of insulin secretion involved in cellular response to glucose stimulus Source: Ensembl
Positive regulation of multicellular organism growth Source: HGNC-UCL
Positive regulation of small intestinal transit Source: Ensembl
Positive regulation of small intestine smooth muscle contraction Source: Ensembl
Positive regulation of sprouting angiogenesis Source: Ensembl
Positive regulation of synapse assembly Source: MGI
Positive regulation of vascular endothelial cell proliferation Source: Ensembl
Postsynaptic modulation of chemical synaptic transmission Source: Ensembl
Regulation of cell population proliferation Source: UniProtKB
Regulation of gastric motility Source: Ensembl
Regulation of postsynapse organization Source: Ensembl
Regulation of response to food Source: GO_Central
Regulation of transmission of nerve impulse Source: Ensembl
Response to electrical stimulus Source: Ensembl
Response to estrogen Source: UniProtKB
Response to hormone Source: UniProtKB

Secreted

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 (PubMed:10604470).
Amidation of Leu-98 is essential for obestatin activity.