Kinetics of protein degradation in diploid and trisomic human fibroblasts
Podobed, O.V.; Golubeva, N.V.; Kukharenko, V.I.; Del'vig, A.A.
Molekuliarnaia Genetika Mikrobiologiia i Virusologiia 1988(5): 41-45
1988
ISSN/ISBN: 0208-0613 PMID: 3412361 Document Number: 321896
The degradation rate of long-lived and short-lived proteins was determined in diploid fibroblasts and fibroblasts with trisomy 7 derived from human embryos. Two fractions of proteins were detected in the exponentially growing diploid fibroblasts with half-lives (T 1/2) 37 and 19 hours. The rate of protein degradation increases in diploid fibroblasts as they approach confluence and protein fractions with T 1/2 30, 18 and 12 hours appear. The rate of protein degradation in trisomic fibroblasts does not change for the long-lived and short-lived proteins and is the same in both exponential (T 1/2 31 and 14 hours) and stationary phase (T 1/2 33 and 17 hours). The relative amount of the short-lived proteins in trisomic fibroblasts in the stationary phase decreased as compared with the one in diploid fibroblasts. It is apparent that a mechanism of regulation of protein catabolism in trisomic fibroblasts is impaired.