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Updated: Jun 11, 2026

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
Published on: December 27, 2016
Involvement of specific integrins in apoptosis induced by vascular apoptosis-inducing protein 1
Satohiko Araki1, Shinako Masuda, Hiroki Maeda
1Marine Biological Laboratory, Graduate School of Science, Nagoya University, Toba, 517-0004, Mie, Japan. saraki@bio.nagoya-u.ac.jp
Abstract:
Hemorrhagic snake venom induces apoptosis in vascular endothelial cells (VEC). In previous reports, we described the purification and cDNA cloning from Crotalus atrox of vascular apoptosis-inducing protein 1 (VAP1) that specifically induces apoptosis in VEC. VAP1 belongs to the metalloprotease/disintegrin family. Yet the mechanism of inducing apoptosis by VAP1 is still not known. Since other various metalloproteases and disintegrins in snake venoms are known to influence extracellular matrix and cell adhesion, we investigated here the involvement of these adhesion molecules in VAP1-induced apoptosis. Consequently, VAP1 induced apoptosis without degrading extracellular matrix or inhibiting adhesion of VEC. However, VAP1-induced apoptosis was inhibited by antibodies for integrin alpha3, alpha6, beta1. Additionally, apoptosis was inhibited by antibody for CD9, an integrin associated protein. These results suggest that integrins are involved in VAP1-induced apoptosis by some specific role rather than that of adhesion to extracellular matrix.
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