Fig. 4

Comparison of NMJ loss in four mouse models indicates diverse patterns of selective vulnerability. The colour gradient legend describes seven classification categories of the NMJ pathology according to the percentage of fully occupied motor endplates in a muscle at disease end-stage (see ‘Methods’ section for more details). The table shows investigated muscles coloured according to their classification categories by percentage of fully occupied endplates in the Smn^-/-;SMN2 [14, 24, 25], Taiwanese [16, 29], SMN∆7 [14, 16, 20, 28] and Smn^2B/- [16, 27] mouse model. The table displays the muscles categorised by body regions (head, neck, back, etc.). Note that for some muscles, different results were observed in two independent studies. This occurred in the AAL, AS and LALc muscles * = [14, 24]; # = [25] in the Smn^-/-;SMN2 model and the LU + = [28];° = [20] in the SMN∆7 model. In the Smn^-/-;SMN2 mouse model, all body regions seem to be moderately affected and display different vulnerability levels, with the most severely affected the muscles in the hindlimb. The Taiwanese mouse model shows very little vulnerability, except for the FDB 2 and FDB 3. The vulnerability pattern in the SMN∆7 mouse model shows that the head, neck and foot muscles are the most affected, followed by ventral core muscles (thoracoabdominal muscles) and the least vulnerability is seen in the limb and back muscles. The Smn^2B/− mouse model displays a regional vulnerability pattern, where the neck muscles, core muscles (thoracoabdominal muscles) and proximal fore- and hindlimbs seem more affected than the head muscles, distal limb and foot muscles