Fig. 4From: Conserved genes and pathways in primary human fibroblast strains undergoing replicative and radiation induced senescenceImmunoblots reveal protein expression levels of markers having a role in induction of senescence. The levels of induction of these proteins in fibroblasts at different cell states are demonstrated (low PD, low PD + 20 Gy irradiation (after 120 h), replicative senescence). The up- or down-regulation was signified by the presence or absence of the bands. p21, p16, IGFBP7, IGFBP3, IGFBP5 were up-regulated to a similar extent in irradiation induced as well as in replicatively senescent cells. In contrast, Id3 was down-regulated in both cases, in replicative stronger than in irradiation induced senescence, and in HFF stronger than in MRC-5 strainsBack to article page