The Intracellular Concentration of Components of the Ubiquitin System in A549 Culture Cells During UV Treatment


Abstract: This study attempts to determine a link between the intracellular components of the ubiquitin (Ub) system and the process of DNA repair in eukaryotes. It is possible to investigate this link in two ways: i. studying the concentration of mRNA for specific Ub components in DNA damaged and controlled cells. ii. studying the concentration of proteins of the Ub system in both DNA damaged and control cells. The specific aim of this study was to try to establish such a link between repair and Ub, by studying and making a quantitative analysis of the intracellular concentrations of both the Ub activating enzyme (E1) and Ub conjugating enzymes (E2) in human A549 tissue culture cells at specific times after UV treatment. Using the techniques of SDS PAGE, western blotting and autoradiography, the result presented here show that levels of components of the Ub sysetm do fluctuate and, in fact, increase after UV treatment. The most noticeable increases occurred for E1 and E2-17kDa two hours after UV treatment. It was also demonstrated that this E2-17kDa can actually become conjugated to Ub, even under normal situations, but the reasons for this still remain unclear. If Ub does play a role in this repair system, it may be possible to detect changes in the concentration of E1 and E2 at specific times after UV treatment.

Keywords: UV Treatment, ubiquitin activating enzyme (E1), ubiquitin conjugating enzyme (E2).

Full Text: PDF