ISSN:
0730-2312
Keywords:
protein kinase C
;
transgenic mouse
;
dynamics after activation
;
prolonged membrane translocation
;
disregulation of late signaling
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Recently, we succeeded in establishing a transgenic mouse line which expressed high levels of protein kinase C (PKC)-alpha in thymocytes at the mRNA level with disproportionately small increases at the protein level. The transgenic PKC-alpha was nevertheless functionally active for inducing accelerated cell growth and IL-2 production by stimulation with anti-receptor (CD3) antibody or phorbol 12-myristate 14-acetate (PMA) in vitro. Study of the dynamics of transgenic PKC-alpha in the cells in vitro showed that the amount of PKC-alpha protein increased in the cells remarkably at ≥ 5 h after stimulation, whereas the level of PKC-alpha mRNA did not change significantly or changed slightly. This suggested that cell activation breaks the posttranscriptional regulation of the transgenic PKC-alpha in resting cells. The increase in PKC-alpha protein accompanied a prolonged membrane translocation of PKC-alpha and enhanced cell proliferation. Such a transgenic effect was inhibited completely by a PKC inhibitor, H-7, added during 0-6 h after the stimulation. These results show formally that the transgenic PKC-alpha whose production was accelerated through cell activation plays a key role in the late (for ≥ 5 h) signal delivery for disregulated cell growth. © 1994 Wiley-Liss, Inc.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcb.240550213
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