Microinjection of smg/rap1/Krev-1 p21 into Swiss 3T3 cells induces DNA synthesis and morphological changes

1992 ◽  
Vol 12 (8) ◽  
pp. 3407-3414
Author(s):  
Y Yoshida ◽  
M Kawata ◽  
Y Miura ◽  
T Musha ◽  
T Sasaki ◽  
...  
Keyword(s):  
Dna Synthesis ◽  
Laser Scanning ◽  
Morphological Changes ◽  
Stress Fibers ◽  
Confocal Laser ◽  
3T3 Cells ◽  
Membrane Ruffling ◽  
Ras P21 ◽  
Swiss 3T3 ◽  
Gamma S

Microinjection of either Ki-rasVal-12 p21 or the GDP-bound form of Ki-ras p21 plus smg GDP dissociation stimulator (GDS), a stimulatory GDP/GTP exchange protein for Ki-ras p21, smg/rap1/Krev-1 p21, and rho p21, into quiescent Swiss 3T3 cells induced DNA synthesis irrespective of the presence or absence of insulin. The guanosine 5'-(3-O-thio)triphosphate (GTP gamma S)-bound form of smg p21B or the GDP-bound form of smg p21B plus smg GDS also induced DNA synthesis but only in the presence of insulin. Either the GDP-bound form of Ki-ras p21 or the same form of smg p21B alone was inactive, but smg GDS alone was slightly active only in the presence of insulin. The morphology of the cells was analyzed by scanning electron, phase-contrast, and confocal laser scanning microscopies. Ki-rasVal-12 p21 induced membrane ruffling irrespective of the presence or absence of insulin. The GTP gamma S-bound form of smg p21B showed the same effect only in the presence of insulin. Either the GDP-bound form of Ki-ras p21, the same form of smg p21B, or smg GDS alone was inactive. Upon microinjection of Ki-rasVal-12 p21, stress fibers markedly decreased and the cells became round and piled up. In contrast, upon microinjection of the GTP gamma S-bound form of smg p21B, stress fibers did not markedly decrease and the cells neither became round nor piled up. These results indicate that both ras p21 and smg p21 are mitogenic in Swiss 3T3 cells but that their actions are slightly different.

scholarly journals Microinjection of smg/rap1/Krev-1 p21 into Swiss 3T3 cells induces DNA synthesis and morphological changes.

1992 ◽  
Vol 12 (8) ◽  
pp. 3407-3414 ◽  
Author(s):  
Y Yoshida ◽  
M Kawata ◽  
Y Miura ◽  
T Musha ◽  
T Sasaki ◽  
...  
Keyword(s):  
Dna Synthesis ◽  
Laser Scanning ◽  
Morphological Changes ◽  
Stress Fibers ◽  
Confocal Laser ◽  
3T3 Cells ◽  
Membrane Ruffling ◽  
Ras P21 ◽  
Swiss 3T3 ◽  
Gamma S

Microinjection of either Ki-rasVal-12 p21 or the GDP-bound form of Ki-ras p21 plus smg GDP dissociation stimulator (GDS), a stimulatory GDP/GTP exchange protein for Ki-ras p21, smg/rap1/Krev-1 p21, and rho p21, into quiescent Swiss 3T3 cells induced DNA synthesis irrespective of the presence or absence of insulin. The guanosine 5'-(3-O-thio)triphosphate (GTP gamma S)-bound form of smg p21B or the GDP-bound form of smg p21B plus smg GDS also induced DNA synthesis but only in the presence of insulin. Either the GDP-bound form of Ki-ras p21 or the same form of smg p21B alone was inactive, but smg GDS alone was slightly active only in the presence of insulin. The morphology of the cells was analyzed by scanning electron, phase-contrast, and confocal laser scanning microscopies. Ki-rasVal-12 p21 induced membrane ruffling irrespective of the presence or absence of insulin. The GTP gamma S-bound form of smg p21B showed the same effect only in the presence of insulin. Either the GDP-bound form of Ki-ras p21, the same form of smg p21B, or smg GDS alone was inactive. Upon microinjection of Ki-rasVal-12 p21, stress fibers markedly decreased and the cells became round and piled up. In contrast, upon microinjection of the GTP gamma S-bound form of smg p21B, stress fibers did not markedly decrease and the cells neither became round nor piled up. These results indicate that both ras p21 and smg p21 are mitogenic in Swiss 3T3 cells but that their actions are slightly different.

Involvement of rho p21 and its inhibitory GDP/GTP exchange protein (rho GDI) in cell motility

1993 ◽  
Vol 13 (1) ◽  
pp. 72-79
Author(s):  
K Takaishi ◽  
A Kikuchi ◽  
S Kuroda ◽  
K Kotani ◽  
T Sasaki ◽  
...  
Keyword(s):  
Cell Motility ◽  
Clostridium Botulinum ◽  
Active Form ◽  
3T3 Cells ◽  
Gtp Binding ◽  
Ras P21 ◽  
Swiss 3T3 ◽  
Adp Ribosyltransferase ◽  
Gamma S ◽  
Exchange Protein

Evidence is accumulating that rho p21, a ras p21-related small GTP-binding protein (G protein), regulates the actomyosin system. The actomyosin system is known to be essential for cell motility. In the present study, we examined the action of rho p21, its inhibitory GDP/GTP exchange protein (named rho GDI), its stimulatory GDP/GTP exchange protein (named smg GDS), and Clostridium botulinum ADP-ribosyltransferase C3, known to selectively ADP-ribosylate rho p21 and to impair its function, in cell motility (chemokinesis) of Swiss 3T3 cells. We quantitated the capacity of cell motility by measuring cell tracks by phagokinesis. Microinjection of the GTP gamma S-bound active form of rhoA p21 or smg GDS into Swiss 3T3 cells did not affect cell motility, but microinjection of rho GDI into the cells did inhibit cell motility. This rho GDI action was prevented by comicroinjection of rho GDI with the GTP gamma S-bound form of rhoA p21 but not with the same form of rhoA p21 lacking the C-terminal three amino acids which was not posttranslationally modified with lipids. The rho GDI action was not prevented by Ki-rasVal-12 p21 or any of the GTP gamma S-bound form of other small GTP-binding proteins including rac1 p21, G25K, and smg p21B. Among these small G proteins, rhoA p21, rac1 p21, and G25K are known to be substrates for rho GDI. The rho GDI action was not prevented by comicroinjection of rho GDI with smg GDS. Microinjection of C3 into Swiss 3T3 cells also inhibited cell motility. These results indicate that the rho GDI-rho p21 system regulates cell motility, presumably through the actomyosin system.

scholarly journals Involvement of rho p21 and its inhibitory GDP/GTP exchange protein (rho GDI) in cell motility.

1993 ◽  
Vol 13 (1) ◽  
pp. 72-79 ◽  
Author(s):  
K Takaishi ◽  
A Kikuchi ◽  
S Kuroda ◽  
K Kotani ◽  
T Sasaki ◽  
...  
Keyword(s):  
Cell Motility ◽  
Clostridium Botulinum ◽  
Active Form ◽  
3T3 Cells ◽  
Gtp Binding ◽  
Ras P21 ◽  
Swiss 3T3 ◽  
Adp Ribosyltransferase ◽  
Gamma S ◽  
Exchange Protein

Evidence is accumulating that rho p21, a ras p21-related small GTP-binding protein (G protein), regulates the actomyosin system. The actomyosin system is known to be essential for cell motility. In the present study, we examined the action of rho p21, its inhibitory GDP/GTP exchange protein (named rho GDI), its stimulatory GDP/GTP exchange protein (named smg GDS), and Clostridium botulinum ADP-ribosyltransferase C3, known to selectively ADP-ribosylate rho p21 and to impair its function, in cell motility (chemokinesis) of Swiss 3T3 cells. We quantitated the capacity of cell motility by measuring cell tracks by phagokinesis. Microinjection of the GTP gamma S-bound active form of rhoA p21 or smg GDS into Swiss 3T3 cells did not affect cell motility, but microinjection of rho GDI into the cells did inhibit cell motility. This rho GDI action was prevented by comicroinjection of rho GDI with the GTP gamma S-bound form of rhoA p21 but not with the same form of rhoA p21 lacking the C-terminal three amino acids which was not posttranslationally modified with lipids. The rho GDI action was not prevented by Ki-rasVal-12 p21 or any of the GTP gamma S-bound form of other small GTP-binding proteins including rac1 p21, G25K, and smg p21B. Among these small G proteins, rhoA p21, rac1 p21, and G25K are known to be substrates for rho GDI. The rho GDI action was not prevented by comicroinjection of rho GDI with smg GDS. Microinjection of C3 into Swiss 3T3 cells also inhibited cell motility. These results indicate that the rho GDI-rho p21 system regulates cell motility, presumably through the actomyosin system.

Morphometric characteristics of the metacestode Echinococcus vogeli Rausch & Bernstein, 1972 in human infections from the northern region of Brazil

2014 ◽  
Vol 89 (4) ◽  
pp. 480-486 ◽  
Author(s):  
F. Almeida ◽  
F. Oliveira ◽  
R. Neves ◽  
N. Siqueira ◽  
R. Rodrigues-Silva ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Morphological Changes ◽  
Northern Region ◽  
Laser Scanning Microscopy ◽  
Health Concern ◽  
Confocal Laser ◽  
Total Width ◽  
Morphometric Characteristics ◽  
Blade Area ◽  
Echinococcus Vogeli

AbstractPolycystic echinococcosis, caused by the larval stage (metacestode) of the small-sized tapeworm, Echinococcus vogeli, is an emerging parasitic zoonosis of great public health concern in the humid tropical rainforests of South and Central America. Because morphological and morphometric characteristics of the metacestode are not well known, hydatid cysts from the liver and the mesentery were examined from patients following surgical procedures. Whole mounts of protoscoleces with rostellar hooks were examined under light and confocal laser scanning microscopy. Measurements were made of both large and small hooks, including the total area, total length, total width, blade area, blade length, blade width, handle area, handle length and handle width. The results confirmed the 1:1 arrangement of hooks in the rostellar pad and indicated, for the first time, that the morphometry of large and small rostellar hooks varies depending upon the site of infection. Light and confocal microscopy images displayed clusters of calcareous corpuscles in the protoscoleces. In conclusion, morphological features of large and small rostellar hooks of E. vogeli are adapted to a varied environment within the vertebrate host and such morphological changes in calcareous corpuscles occur at different stages in the maturation of metacestodes.

scholarly journals rac p21 is involved in insulin-induced membrane ruffling and rho p21 is involved in hepatocyte growth factor- and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced membrane ruffling in KB cells.

1994 ◽  
Vol 14 (4) ◽  
pp. 2447-2456 ◽  
Author(s):  
T Nishiyama ◽  
T Sasaki ◽  
K Takaishi ◽  
M Kato ◽  
H Yaku ◽  
...  
Keyword(s):  
Growth Factor ◽  
Hepatocyte Growth Factor ◽  
Phorbol Ester ◽  
Kb Cells ◽  
Induced Membrane ◽  
Membrane Ruffling ◽  
Kinase C ◽  
Ras P21 ◽  
Gamma S ◽  
Hepatocyte Growth

Insulin and hepatocyte growth factor (HGF) induced morphologically different membrane rufflings in KB cells. Insulin-induced membrane ruffling was inhibited by microinjection of rho GDI, an inhibitory GDP/GTP exchange regulator for both rho p21 and rac p21 small GTP-binding proteins, but not inhibited by microinjection of botulinum exoenzyme C3, known to selectively ADP-ribosylate rho p21 and to impair its function. This rho GDI action was prevented by comicroinjection with guanosine 5'-(3-O-thio)triphosphate (GTP gamma S)-bound rac1 p21. In contrast, HGF-induced membrane ruffling was inhibited by microinjection of rho GDI or C3. This rho GDI action was prevented by comicroinjection with GTP gamma S-bound rhoA p21, and this C3 action was prevented by comicroinjection with GTP gamma S-bound rhoAIle-41 p21, which is resistant to C3. Microinjection of either GTP gamma S-bound rac1 p21 or rhoA p21 alone induced membrane ruffling in the absence of the growth factors. The rac1 p21-induced membrane ruffling was morphologically similar to the insulin-induced kind, whereas rhoA p21-induced ruffling was apparently different from both the insulin- and HGF-induced kinds. Membrane ruffling was also induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), a protein kinase C-activating phorbol ester, but not by Ca2+ ionophore or microinjection of a dominant active Ki-ras p21 mutant (Ki-rasVal-12 p21). The phorbol ester-induced membrane ruffling was morphologically similar to the rhoA p21-induced kind and inhibited by microinjection of rho GDI or C3. These results indicate that rac p21 and rho GDI are involved in insulin-induced membrane ruffling and that rho p21 and rho GDI are involved in HGF- and phorbol ester-induced membrane rufflings.

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