Figure 3. Alteration of the potential landscapes in C2C12 differentiation.

(A) The first three PCA loading vectors calculated from Raman spectra of the nuclei at Day -3, Day 0 and Day 3. (B) Similarity between the averaged residual component of the Raman spectra of myotubes (Day 7-MT), which is given by subtraction of PC1–3 (black) and a Raman spectrum of a coverslip made of borosilicate glass (grey). (C) Plot of scores for PC1 and PC2. Each marker shows the average value of the scores for PC1 and PC2 of the Raman spectra obtained from single nuclei. Error bars show the SDs of the score values from the same nuclei. (D) Potential landscapes at Day -3, Day 3 and Day 7-MT on the PC1-PC2 plane, which were estimated from U(t) = −ln(P(t)). The counter plots corresponding to the potential landscapes are also shown. Cells in the homogeneous state at Day -3 started to show heterogeneity at Day 3 and became homogeneous again at Day 7. Note that the centre of the attractors for myoblasts and myotubes, indicated by pink and blue pins, respectively, are at different locations on the PC1-PC2 plane.