Single Amino Acid (Arginine) Deprivation Induces G1 Arrest Associated with Inhibition of Cdk4 Expression in Cultured Human Diploid Fibroblasts
Authors: Lamb J.; Wheatley D.N.
Source: Experimental Cell Research, Volume 255, Number 2, March 2000 , pp. 238-249(12)
Publisher: Academic Press
Abstract:
Withdrawal of a single amino acid (arginine) from freely cycling early passage primary human fibroblasts caused a halt to proliferation, characterized by an accumulation of cells in the G1 phase of the cell cycle. This arrest was accompanied by the suppression of cyclin D1- and cyclin E-associated kinase activities and the appearance of hypophosphorylated retinoblastoma protein. Arginine-deprived cells remained viable for in excess of 4 days and could be made to synchronously reenter the cell cycle by restoration of the amino acid, with kinetics characteristic of exit from a quiescent state. Stimulation of cells arrested by serum withdrawal did not result in S-phase entry when arginine was omitted from the culture medium. Although cyclin D1 accumulated on normal schedule, cdk4, which increased following restimulation in amino acid-replete medium, was not induced when arginine was absent. These results suggest that arginine deprivationin common with other suboptimal conditionsinhibits the passage of normal human cells through the restriction point and implicate cdk4 as the key regulatory element in amino acid-sensitive cell cycle control. Copyright 2000 Academic Press.
Keywords: amino acid deprivation; arginine; restriction point; cell cycle arrest; cdk4
Language: English
Document Type: Research article
Affiliations: Department of Cell Pathology, University of Aberdeen, MacRobert Building, 581 King Street, Aberdeen, AB24 5UA, Scotland, United Kingdom:

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