Genomic fragment containing shi. A Tag:FLAG-Tag:CALI(4C) tag has been inserted into the middle domain of the shi gene. The presence of the Tag:CALI(4C) tag means that FlAsH-mediated fluorescein-assisted light inactivation can be used to inactivate the protein produced.
bouton | conditional, with shi1
Inactivation of the shiT:Zzzz\FLAG,T:Zzzz\4C protein using FlAsH-mediated fluorescein-assisted light inactivation in shi12.12B flies carrying shiT:Zzzz\FLAG,T:Zzzz\4C results in a fast drop in the EJP amplitude at intense (10Hz) stimulation.
Stimulation of boutons in which shi function has been inactivated (using FlAsH-mediated fluorescein-assisted light inactivation to photo-inactivate shiT:Zzzz\FLAG,T:Zzzz\4C in shi12.12B flies carrying shiT:Zzzz\FLAG,T:Zzzz\4C) results in accumulation of large membraneous profiles, some of which are seen to be connected to the presynaptic membrane. In addition, there is an almost complete lack of normal-size synaptic vesicles in the synaptic terminal.
shi1/Y ; shiT:Zzzz\FLAG,T:Zzzz\4C animals at the restrictive temperature (without photo-inactivating shiT:Zzzz\FLAG,T:Zzzz\4C) show a block in membrane uptake upon stimulation of boutons compared to controls at 22[o]C and show accumulation of invaginated pits. In shi1/Y ; shiT:Zzzz\FLAG,T:Zzzz\4C animals at the permissive temperature in which shiT:Zzzz\FLAG,T:Zzzz\4C has been photo-inactivated, large membrane inclusions are seen in the boutons after stimulation. Membrane accumulations in stimulated boutons are also seen at the restrictive temperature in shi1/Y ; shiT:Zzzz\FLAG,T:Zzzz\4C animals in which shiT:Zzzz\FLAG,T:Zzzz\4C has been photo-inactivated, but accumulation of invaginated pits is not seen in this case.
shiT:Zzzz\FLAG,T:Zzzz\4C fully rescues the lethality of shi12.12B mutants, and the rescued animals have no obvious behavioural, developmental or electrophysiological defects.