Quantification of the Spatial Organization of the Nuclear Lamina as a Tool for Cell Classification
Figure 1
(a) Confocal microscopy images of living cells expressing LMNA fused to GFP in human mesenchymal stem cells (cross-sections are shown). LMNA-GFP transgene was expressed in cells by a lentivirus expression system. Spatial changes in the structure of the nuclear lamina are shown in a lateral (x,y)-plane and in a (x,z)-plane. The top shows a typical nucleus of an early passage from a 35-year-old donor. Bottom left shows a nucleus from the same donor but at a late passage number. This exemplifies how the nuclear lamina structure changes in senescent cells. Bottom right panel depicts a typical nucleus of an early passage cell from an 81-year-old donor. (b) LMNA is redistributed at the nuclear lamina concurrent with the change in the shape. The “even distribution” at the “short edges” of the structure in young cells (upper left) becomes more heterogeneous along the nuclear lamina for the older cell (bottom left). Protein accumulation is illustrated with red for high values and blue for low values; the color scale is linear. The curvature of the lamina locally increases along the structure (lower right) compared to the young cell (upper right). Red indicates high curvature values and blue low values; the scale is logarithmic. The sections shown match the cross-sections in (a).
