TY - JOUR
T1 - Effects of the phosphatase inhibitors, okadaic acid, ATPγS, and calyculin A on the dividing sand dollar egg
AU - Hamaguchi, Yukihisa
AU - Kuriyama, Ryoko
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2002/6
Y1 - 2002/6
N2 - The effects of the phosphatase inhibitors, okadaic acid (OA), adenosine 5′-O-(3-thiotriphosphate) (ATPγS), and calyculin A (CL-A) on anaphase chromosome movement, cytokinesis, and cytoskeletal structures at cell division were examined by being microinjected into mitotic sand dollar eggs. When OA was injected, chromosome movement was inhibited and, moreover, chromosomes were ejected from the polar regions of the mitotic apparatus. By immunofluorescence, microtubules were observed to be severed in the OA-injected eggs, causing the smooth cell surface to be changed to an irregular surface. When ATPγS and CL-A were injected, the effect on cell shape was remarkable: In dividing eggs, furrowing stopped within several seconds after injection, small blebs appeared on the cell surface and became large, spherical or dumbbell cell shapes then changed to irregular forms, and subsequently cytoplasmic flow occurred. Microfilament detection revealed that actin accumulation in the cortex, which was not limited to the furrow cortex, occurred shortly after injection. Cortical accumulation of actin is thought to induce force generation and random cortical contraction, and accordingly to result in bleb extrusion from the cortex. Consequently, the phosphatase inhibitors inhibited the transition from mitosis to interphase by mediating cortical accumulation of actin filaments and/or fragmentation of microtubules.
AB - The effects of the phosphatase inhibitors, okadaic acid (OA), adenosine 5′-O-(3-thiotriphosphate) (ATPγS), and calyculin A (CL-A) on anaphase chromosome movement, cytokinesis, and cytoskeletal structures at cell division were examined by being microinjected into mitotic sand dollar eggs. When OA was injected, chromosome movement was inhibited and, moreover, chromosomes were ejected from the polar regions of the mitotic apparatus. By immunofluorescence, microtubules were observed to be severed in the OA-injected eggs, causing the smooth cell surface to be changed to an irregular surface. When ATPγS and CL-A were injected, the effect on cell shape was remarkable: In dividing eggs, furrowing stopped within several seconds after injection, small blebs appeared on the cell surface and became large, spherical or dumbbell cell shapes then changed to irregular forms, and subsequently cytoplasmic flow occurred. Microfilament detection revealed that actin accumulation in the cortex, which was not limited to the furrow cortex, occurred shortly after injection. Cortical accumulation of actin is thought to induce force generation and random cortical contraction, and accordingly to result in bleb extrusion from the cortex. Consequently, the phosphatase inhibitors inhibited the transition from mitosis to interphase by mediating cortical accumulation of actin filaments and/or fragmentation of microtubules.
KW - Actin
KW - Chromosome movement
KW - Cleavage furrow
KW - Microtubule
KW - Phosphatase inhibitor
KW - Sand dollar egg
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U2 - 10.1247/csf.27.127
DO - 10.1247/csf.27.127
M3 - Article
C2 - 12207043
AN - SCOPUS:0036622316
SN - 0386-7196
VL - 27
SP - 127
EP - 137
JO - Cell Structure and Function
JF - Cell Structure and Function
IS - 3
ER -