TY - JOUR
T1 - Pacific oyster hemocytes undergo apoptosis following cell-adhesion mediated by integrin-like molecules
AU - Terahara, Kazutaka
AU - Takahashi, Keisuke G.
AU - Mori, Katsuyoshi
N1 - Funding Information:
This study was supported in part by a Grant-in-Aid for scientific research (15580156) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan. We thank the staff of the Education and Research Center of Marine Biosources at Onagawa, Tohoku University, for their help in our experiments.
PY - 2005/6
Y1 - 2005/6
N2 - Previously, we demonstrated that in the Pacific oyster (Crassostrea gigas, a bivalve mollusc) apoptosis could be induced in hemocytes by treatment with Arg-Gly-Asp (RGD) peptides which are known to function as an integrin ligand. However, it is unclear where the RGD peptides are binding to the C. gigas hemocytes, or what mechanism or molecules are involved, e.g., integrin-ligand interactions. Therefore, this study was undertaken to investigate the binding interactions in C. gigas hemocytes. Initially, to confirm the presence of RGD-recognizing integrin-like molecule(s) on the hemocytes, we assessed the enhancement of spreading ability, and found that spreading ability was enhanced by immobilized human fibronectin, a fibronectin fragment containing the RGD motif, and C. gigas plasma in the presence of divalent cations. Interestingly, viability of the spreading hemocytes dramatically decreased 24 h later and DNA fragmentation with oligonucleosomal laddering of 180-200 bp in length was detected in the dead hemocytes by electrophoresis and TUNEL assay. These results indicated that hemocyte adhesion mediated by integrin-like molecules triggered apoptosis and suggested that integrin-activation contributes to the induction of apoptosis. This is the first report showing the possibility of an integrin functioning in the induction of apoptosis in invertebrate hemocytes.
AB - Previously, we demonstrated that in the Pacific oyster (Crassostrea gigas, a bivalve mollusc) apoptosis could be induced in hemocytes by treatment with Arg-Gly-Asp (RGD) peptides which are known to function as an integrin ligand. However, it is unclear where the RGD peptides are binding to the C. gigas hemocytes, or what mechanism or molecules are involved, e.g., integrin-ligand interactions. Therefore, this study was undertaken to investigate the binding interactions in C. gigas hemocytes. Initially, to confirm the presence of RGD-recognizing integrin-like molecule(s) on the hemocytes, we assessed the enhancement of spreading ability, and found that spreading ability was enhanced by immobilized human fibronectin, a fibronectin fragment containing the RGD motif, and C. gigas plasma in the presence of divalent cations. Interestingly, viability of the spreading hemocytes dramatically decreased 24 h later and DNA fragmentation with oligonucleosomal laddering of 180-200 bp in length was detected in the dead hemocytes by electrophoresis and TUNEL assay. These results indicated that hemocyte adhesion mediated by integrin-like molecules triggered apoptosis and suggested that integrin-activation contributes to the induction of apoptosis. This is the first report showing the possibility of an integrin functioning in the induction of apoptosis in invertebrate hemocytes.
KW - Apoptosis
KW - Bivalve
KW - Crassostrea gigas
KW - Fibronectin
KW - Hemocyte
KW - Integrin
KW - Invertebrate
KW - Mollusc
KW - Pacific oyster
KW - RGD
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U2 - 10.1016/j.cbpb.2005.05.040
DO - 10.1016/j.cbpb.2005.05.040
M3 - Article
C2 - 15990346
AN - SCOPUS:22044433674
VL - 141
SP - 215
EP - 222
JO - Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
JF - Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
SN - 1095-6433
IS - 2
ER -