Assembly, Release, and Transport of Airway Mucins in Pigs and Humans.

ABSTRACT: The respiratory system is protected from inhaled particles and microbes by the mucociliary system. This system differs between animal species, where pigs and humans have numerous submucosal glands. The polymer-forming mucin, MUC5B, is packed in a highly organized way in granules of the mucus-secreting cells in the glands. Upon secretion, the packed MUC5B is flushed out by a chloride- and bicarbonate-rich fluid from the cystic fibrosis transmembrane conductance regulator-expressing serosal cells located at the most distal part of the gland. The bicarbonate raises the pH and removes calcium from the N terminus of MUC5B, allowing the mucin to be pulled out into a linear polymer. Thousands of such polymers gather in bundles in the submucosal gland duct, and these bundles appear at the opening

SUBMITTER: Ermund A 

PROVIDER: S-EPMC6855098 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature