proopiomelanocortin
Pronunciation: /ˌproʊoʊpaɪoʊˌmɛlənoʊˈkɔrtɪn/
Also written as: POMC — Proopiomelanocortin
A large precursor polypeptide that undergoes post-translational processing to yield multiple bioactive peptides including ACTH, β-endorphin, and melanocyte-stimulating hormones.
Full Definition
Proopiomelanocortin (POMC) is a 267-amino acid precursor polypeptide synthesized primarily in the anterior pituitary corticotrophs and hypothalamic arcuate nucleus neurons. Through tissue-specific enzymatic cleavage by prohormone convertases, POMC generates several important bioactive peptides including adrenocorticotropic hormone (ACTH), β-endorphin, and various melanocyte-stimulating hormones (α-, β-, and γ-MSH). In the pituitary, POMC processing primarily yields ACTH and β-endorphin, while in the hypothalamus, further processing produces melanocortins involved in appetite regulation and energy homeostasis. POMC neurons are key regulators of the hypothalamic-pituitary-adrenal axis and feeding behavior.
Usage
Usage note: Note the distinction from 'pro-opiomelanocortin' - proopiomelanocortin is the full precursor form.
In Context
- "The patient exhibited a proopiomelanocortin gene mutation resulting in severe early-onset obesity." — Genetic consultation report
- "Proopiomelanocortin processing was abnormal in the pituitary adenoma specimen." — Pathology report