Profiles of the thermal unfolding of nesprin-1α fragments recorded at 222 nm (A–D) and the first order derivatives of the unfolding curves, respectively (E–H), as well as the AD spectra before and after thermal unfolding (I). A and E represent the unfolding of SLR2-5; B and F represent the unfolding of SLR5-7; C and G represent the unfolding of SLR2-7ΔAD; D and H represent the unfolding of SLR2-7. SLR2-5 and SLR2-7ΔAD are shown as open and closed circles, respectively (n = 2); SLR5-7 and SLR2-7 are shown as open and closed circles, respectively (n = 3, but 2 representative samples are shown). The apparent sample to sample variation for fragments SLR5-7 and SLR2-7, compared to other two pure SLR fragments, may be due to the effects of the adaptive domain. The unfolding of AD was maintained in 101 °C for 1 hour to reach equilibrium and the spectra are repeated twice and the average value is plotted. Each trial (n) includes the repeat of protein expression, purification and unfolding; independent repeats from the same preparation were indistinguishable.