Stimulation of autophosphorylation of liver cell membrane proteins by calcium and partial hepatectomy
β Scribed by J. P. MacManus; J. F. Whitfield
- Publisher
- John Wiley and Sons
- Year
- 1981
- Tongue
- English
- Weight
- 880 KB
- Volume
- 106
- Category
- Article
- ISSN
- 0021-9541
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β¦ Synopsis
Abstract
Partial hepatectomy in the rat stimulated the phosphorylation of three proteins (Mr 100,000, 48,000, and 35,000) in the plasma membranes of the proliferatively activated cells of the liver remnant. The autophosphorylation of these plasma membrane proteins began to rise about 8 hours after surgery, peaked at 14 hours, and then returned to the original low level by 24 hours. This increase in autophosphorylation was not evident in isolated plasma membranes from other proliferatively activated liver cells, such as those in fetal liver or hepatomas. The protein kinase responsible for the phosphorylation of the three membrane proteins was activated by calcium but appeared both cyclicβAMPβ and calmodulinindependent.
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