Mucin gene-structure and -expression: protection versus
adhesion.
Van, B. Jan-Willem, Klinken, Jan Dekker, Hans A. B[umlaut]uller,
Alexandra W. C. Einerhand).
Pediatric Gastroenterology and Nutrition, Academic Medical Center,
Amsterdam, The Netherlands
APStracts 2:0175G, 1995.
Looking back over the past 5 years of mucin research, the cloning of
mucin cDNAs brought about by the application of molecular biology and
molecular analyses, constitutes a major step in understanding mucin
structure and function. Here two classes of mucins are described:
epithelium associated and endothelium/leuco cyte associated mucins,
which were thus far described separately in the literature. The
epithelial mucins are generally believed to play a role in cyto
-protection. The endothelial and leucocyte class of mucins are
adhesion molecules involved in lymphocyte homing, lymphocyte
activation, or are part of the adhesion cascade which plays a role in
the initiation of inflammation. Mucins in general contain many
threonine and serine residues which are extensively O-glycosylated.
Due to this profound glycosylation mucins have an filamentous
conformation. By virtue of the extended filamentous, and often
negatively charged, structure mucins can act as a barrier protecting
the cell. However, when an opposing cell has specific receptors for
mucins, adhesion can override the barrier function. Therefore, mucins
may be powerful two-edged swords: they are both protective and
adhesive.
Received 12 June 1995; accepted in final form 17 August 1995.
APS Manuscript Number G246-5.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 August 1995.