Signaling mucins: the new kids on the MAPK block.
Signaling mucins are an emerging group of cell adhesion receptors that activate mitogen-activated protein kinase (MARK) pathways at the level of RAS/RHO. Recent discoveries on several fronts, including in the model eukaryote budding yeast, have broadened our understanding of this family of signaling molecules. Progress in characterizing three signaling mucins, MUC1, Muc4, and Msb2, points to a surprising degree of functional overlap in the regulation and mechanism-of-activation of these molecules. The prevailing new insight is one of receptor activation by proteolytic cleavage that closely mirrors the developmental signaling factor, Notch. The unexpected parallels between signaling mucins and Notch spark new questions about mucin activation and provoke a double take at this fledgling class of signaling adhesion molecule.
Cullen
Paul J
PJ
Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY 14260-1300, USA. pjcullen@buffalo.edu
D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D016764:Cell Polarity; D005246:Feedback; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D047908:Intracellular Signaling Peptides and Proteins; D020935:MAP Kinase Signaling System / Q000235:genetics / Q000502:physiology*; D008562:Membrane Glycoproteins; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D055264:Mucin-4; D009077:Mucins / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D011956:Receptors, Cell Surface / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
C110690:FLO11 protein, S cerevisiae; D020690:GTPase-Activating Proteins; D047908:Intracellular Signaling Peptides and Proteins; C076360:MSB2 protein, S cerevisiae; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D055264:Mucin-4; D009077:Mucins; D011956:Receptors, Cell Surface; D029701:Saccharomyces cerevisiae Proteins