Fig. 9. Synaptic sites are singly innervated in Musk mutant mice
expressing MCK-MMT but nerve terminal arbors are simplified. Synapses
are singly innervated in muscle from 3-week-old Musk-/-;
MCK-MMT mice, similar to wild-type and Musk-/-;
MCK-Musk mice. Nerve terminals are similarly arborized in wild-type and
Musk-/-; MCK-Musk mice (A-C), but in
Musk-/-; MCK-MMT mice, nerve terminal differentiation is
incomplete, ranging from terminals with less complex arbors (D) to nerve
terminals with strikingly simplified arbors and bouton-like endings (E,F).
Wholemounts of diaphragm muscles from three 3-week-old mice were stained with
antibodies to neurofilament (NF) and synaptophysin (Syn) to label axons and
presynaptic nerve terminals, respectively, and with Texas-Red
-Bungarotoxin (TR-
-BGT) to label AChRs. Scale bar: 20 µm.