Pituitary adenylate cyclase-activating peptide

Pituitary adenylate cyclase-activating polypeptide also known as PACAP is a is_associated_with::protein that in humans is encoded by the ADCYAP1 is_associated_with::gene. PACAP is similar to is_associated_with::vasoactive intestinal peptide. One of its effects is to stimulate is_associated_with::enterochromaffin-like cells. It binds to is_associated_with::vasoactive intestinal peptide receptor and to the PACAP receptor.

Function
This gene encodes adenylate cyclase-activating polypeptide 1. Mediated by adenylate cyclase-activating polypeptide 1 receptors, this polypeptide stimulates adenylate cyclase and subsequently increases the cAMP level in target cells. Adenylate cyclase-activating polypeptide 1 not only is a hypophysiotropic hormone (i.e. a substance that induces activity in the hypophysis) but also functions as a is_associated_with::neurotransmitter and neuromodulator. In addition, it plays a role in paracrine and autocrine regulation of certain types of cells. This gene is composed of five exons. Exons 1 and 2 encode the 5' UTR and signal peptide, respectively; exon 4 encodes an adenylate cyclase-activating polypeptide 1-related peptide; and exon 5 encodes the mature peptide and 3' UTR. This gene encodes three different mature peptides, including two isotypes: a shorter form and a longer form.

Recently a version of this gene has been associated with is_associated_with::post-traumatic stress disorder (PTSD) in women (but not men). This disorder involves a maladaptive psychological response to traumatic, i.e. existence-threatening, events. Ressler et al. identified an association of a SNP in the gene coding for pituitary adenylate cyclase-activating polypeptide (PACAP), implicating this peptide and its receptor (PAC1) in PTSD.

Interactions
Pituitary adenylate cyclase-activating peptide has been shown to interact with is_associated_with::Secretin receptor.