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Updated: Jun 19, 2026

Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
Vav and Rac activation in B cell antigen receptor endocytosis involves Vav recruitment to the adapter protein LAB
Shikha Malhotra1, Susan Kovats2, Weiguo Zhang3
1Immunobiology and Cancer Program, Oklahoma Medical Research Foundation, and Department of Cell Biology, University of Oklahoma, Oklahoma City, Oklahoma 73104.
Abstract:
The signal transduction events supporting B cell antigen receptor (BCR) endocytosis are not well understood. We have identified a pathway supporting BCR internalization that begins with tyrosine phosphorylation of the adapter protein LAB. Phosphorylated LAB recruits a complex of Grb2-dynamin and the guanine nucleotide exchange factor Vav. Vav is required for activation of the small GTPases Rac1 and Rac2. All these proteins contribute to (and dynamin, Vav, and Rac1/2 are required for) BCR endocytosis and presentation of antigen to T cells. This is the first description of a sequential signal transduction pathway from BCR to internalization and antigen presentation.
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