PACS-1 and adaptor protein-1 mediate ACTH trafficking to the regulated secretory pathway

Biochem Biophys Res Commun. 2018 Dec 9;507(1-4):519-525. doi: 10.1016/j.bbrc.2018.11.085. Epub 2018 Nov 17.


The regulated secretory pathway is a specialized form of protein secretion found in endocrine and neuroendocrine cell types. Pro-opiomelanocortin (POMC) is a pro-hormone that utilizes this pathway to be trafficked to dense core secretory granules (DCSGs). Within this organelle, POMC is processed to multiple bioactive hormones that play key roles in cellular physiology. However, the complete set of cellular membrane trafficking proteins that mediate the correct sorting of POMC to DCSGs remain unknown. Here, we report the roles of the phosphofurin acidic cluster sorting protein - 1 (PACS-1) and the clathrin adaptor protein 1 (AP-1) in the targeting of POMC to DCSGs. Upon knockdown of PACS-1 and AP-1, POMC is readily secreted into the extracellular milieu and fails to be targeted to DCSGs.

Keywords: Adaptor proteins; Endocrinology; Membrane trafficking; PACS-1; Regulated secretory pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Protein Complex 1 / metabolism*
  • Adaptor Protein Complex 3 / metabolism
  • Adrenocorticotropic Hormone / metabolism*
  • Animals
  • Cell Line
  • Lysosomes / metabolism
  • Mice
  • Pro-Opiomelanocortin / metabolism
  • Protein Binding
  • Secretory Pathway*
  • Vesicular Transport Proteins / metabolism*


  • Adaptor Protein Complex 1
  • Adaptor Protein Complex 3
  • Pacs1 protein, mouse
  • Vesicular Transport Proteins
  • Pro-Opiomelanocortin
  • Adrenocorticotropic Hormone