Growing evidence suggests that cytoplasmic actin filaments are key players in the internal orchestration between cell and nuclear shape.Here we show that orientation and deformation of the nucleus are regulated by lateral compressive forces driven by tension in central actomyosin fibres.We reveal that tension in central stress fibres is gradually generated by anisotropic force contraction dipoles,which expand as the cell elongates and spreads.Our findings indicate that large-scale cell shape changes induce a drastic condensation of chromatin and affect cell proliferation.Using Structured Illumination Microscopy (SIM) in combination with confocal microscopy,we show that tension in apical actin stress fibers leads to deep nuclear indentations due to nuclear lamina deformations.