Expressing Hsap\SETXT3I.UAS under the control of Scer\GAL4Act5C.PU leads to larval neuromuscular junctions with significantly more and smaller boutons, as compared to controls; these boutons also show increased frequency of Futsch loops. There are no changes in neurotransmission under basal conditions (spontaneous miniature and evoked excitatory junction potential, and quantal content) or under high frequency stimulation (evoked excitatory junction potential amplitude), as compared to controls.