Figure 2. BrdU labeling demonstrates... | Rockefeller University Press

Figure 2.

$Figure 2. BrdU labeling demonstrates that distended satellites are characteristic of and specific to senescent fibroblasts. (A) Satellites do not distend in quiescent, serum-starved cells. (B and C) BrdU (red) labels cells with condensed satellites (green; B) but not cells with decondensed satellites (C). Inset shows high magnification of a distended satellite (arrowhead; cells are from same field). (D and E) Quantification of satellite distension in early (D) and late (E) passage cultures subjected to a 20-min BrdU pulse, confirming that cells with decondensed satellites are rarely in S phase. (F) Almost all cells that did not incorporate BrdU during a 48-h pulse had distended satellites (n = 100–200, from one of three repeats). (G) Early passage and senescent cells with distended satellites rarely incorporate BrdU during the previous 48-h period (n = 100–200, representative of one of three repeats). In presenescent late passage cultures in which more cells are entering senescence, a significant fraction of cells with distended satellites incorporated BrdU (error bars represent standard error).$

BrdU labeling demonstrates that distended satellites are characteristic of and specific to senescent fibroblasts. (A) Satellites do not distend in quiescent, serum-starved cells. (B and C) BrdU (red) labels cells with condensed satellites (green; B) but not cells with decondensed satellites (C). Inset shows high magnification of a distended satellite (arrowhead; cells are from same field). (D and E) Quantification of satellite distension in early (D) and late (E) passage cultures subjected to a 20-min BrdU pulse, confirming that cells with decondensed satellites are rarely in S phase. (F) Almost all cells that did not incorporate BrdU during a 48-h pulse had distended satellites (n = 100–200, from one of three repeats). (G) Early passage and senescent cells with distended satellites rarely incorporate BrdU during the previous 48-h period (n = 100–200, representative of one of three repeats). In presenescent late passage cultures in which more cells are entering senescence, a significant fraction of cells with distended satellites incorporated BrdU (error bars represent standard error).