The recycling and transcytotic pathways for IgG transport by FcRn are distinct and display an inherent polarity
Year: 2009
Type: article
Abstract: The Fc receptor FcRn traffics immunoglobulin G (IgG) in both directions across polarized epithelial cells that line mucosal surfaces, contributing to host defense. We show that FcRn traffics IgG from either apical or basolateral membranes into the recycling endosome (RE), after which the actin motor myosin Vb and the GTPase Rab25 regulate a sorting step that specifies transcytosis without affecting recycling. Another regulatory component of the RE, Rab11a, is dispensable for transcytosis, but regulates recycling to the basolateral membrane only. None of these proteins affect FcRn trafficking away from lysosomes. Thus, FcRn transcytotic and recycling sorting steps are distinct. These results are consistent with a single structurally and functionally heterogeneous RE compartment that traffics FcRn to both cell surfaces while discriminating between recycling and transcytosis pathways polarized in their direction of transport.
Source: The Journal of Cell Biology
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: hybrid
Awards: G1036049148, Rnd Effector Molecules in Epithelial Cell Transformation, Molecular characteristics of the apical recycling system, FcRn-dependent sorting of IgG and IgG-opsinized antigens by epithelial cells, Molecular characteristics of the apical recycling system, Intestinal Immune Regulation by IgG and FcRn, G5857948765, G6325015508, G9000340342, Integrated Epithelial and Muscosal Biology, Small GTP Binding Proteins in Gastrointestinal Mucosa, Boston Area Nutrition Obesity Research Center (NORC)
OpenAlex ID: W2137960793