Extended Data Fig. 4: Illustration of the parametrization of stretch curves.
From: Ion-mediated condensation controls the mechanics of mitotic chromosomes
(A) The linear stiffness is determined as the slope of a linear fit to the initial part of the stretch curve. (B) The critical force is determined by fitting a stepwise function to the stiffness as a function of force. Data is resampled on a logarithmic force scale. (C) Box plot of the stiffening exponent (slope of high force part in panel B) in the absence and presence of polyamines (N = 25 chromosomes) or PEG (N = 12 chromosomes) confirming that the characteristic non-linear stiffening of chromosomes is not impacted by ion-mediated condensation. The box plot marks the quartiles of the distribution, the whiskers show the whole distribution, and the center line marks the median.
