Semaphorin-induced cytoskeletal collapse and repulsion of endothelial cells.
Class 3 semaphorins (SEMA3) are mediators of neuronal guidance first shown to repel axons and collapse axonal growth cones by depolymerization of cytoskeletal F-actin. Subsequently, it was found that SEMA3 could also mediate angiogenesis. SEMA3F binds to its receptor, neuropilin 2 (NRP2), a transmembrane protein expressed on neurons, EC (EC), and tumor cells. In vitro, SEMA3F collapses the F-actin cytoskeleton, repels EC, and inhibits EC and tumor cell adhesion and migration in a manner similar to what occurs with axons. In a mouse tumor model, SEMA3F is a potent inhibitor of tumor angiogenesis, tumor progression, and metastasis. SEMA3F is encoded in a region of chromosome 3p21.3 that is commonly deleted in small cell lung cancers, suggesting that SEMA3F is a tumor suppressor. SEMA3F may have therapeutic potential. Therefore, this chapter is focused primarily on the detailed methods to purify SEMA3F and to assay its biologic activity, including cytoskeleton collapse and repulsion.
Bielenberg
Diane R
DR
Department of Surgery, Childrens Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Shimizu
Akio
A
Klagsbrun
Michael
M
D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D014162:Transfection
D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; C491230:SEMA3F protein, human