Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - A drosophila SNAP-25 null mutant reveals context-dependent redundancy with SNAP-24 in neurotransmission
AU - Vilinsky, Ilya
AU - Stewart, Bryan A.
AU - Drummond, James
AU - Robinson, Iain
AU - Deitcher, David L.
PY - 2002/9/1
Y1 - 2002/9/1
N2 - The synaptic protein SNAP-25 is an important component of the neurotransmitter release machinery, although its precise function is still unknown. Genetic analysis of other synaptic proteins has yielded valuable information on their role in synaptic transmission. In this study, we performed a mutagenesis screen to identify new SNAP-25 alleles that fail to complement our previously isolated recessive temperature-sensitive allele of SNAP-25, SNAP-25ts. In a screen of 100,000 flies, 26 F1 progeny failed to complement SNAP-25ts and 21 of these were found to be null alleles of SNAP-25. These null alleles die at the pharate adult stage and electroretinogram recordings of these animals reveal that synaptic transmission is blocked. At the third instar larval stage, SNAP-25 nulls exhibit nearly normal neurotransmitter release at the neuromuscular junction. This is surprising since SNAP-25ts larvae exhibit a much stronger synaptic pheno-type. Our evidence indicates that a related protein, SNAP-24, can substitute for SNAP-25 at the larval stage in SNAP-25 nulls. However, if a wild-type or mutant form of SNAP-25 is present, then SNAP-24 does not appear to take part in neurotransmitter release at the larval NMJ. These results suggest that the apparent redundancy between SNAP-25 and SNAP-24 is due to inappropriate genetic substitution.
AB - The synaptic protein SNAP-25 is an important component of the neurotransmitter release machinery, although its precise function is still unknown. Genetic analysis of other synaptic proteins has yielded valuable information on their role in synaptic transmission. In this study, we performed a mutagenesis screen to identify new SNAP-25 alleles that fail to complement our previously isolated recessive temperature-sensitive allele of SNAP-25, SNAP-25ts. In a screen of 100,000 flies, 26 F1 progeny failed to complement SNAP-25ts and 21 of these were found to be null alleles of SNAP-25. These null alleles die at the pharate adult stage and electroretinogram recordings of these animals reveal that synaptic transmission is blocked. At the third instar larval stage, SNAP-25 nulls exhibit nearly normal neurotransmitter release at the neuromuscular junction. This is surprising since SNAP-25ts larvae exhibit a much stronger synaptic pheno-type. Our evidence indicates that a related protein, SNAP-24, can substitute for SNAP-25 at the larval stage in SNAP-25 nulls. However, if a wild-type or mutant form of SNAP-25 is present, then SNAP-24 does not appear to take part in neurotransmitter release at the larval NMJ. These results suggest that the apparent redundancy between SNAP-25 and SNAP-24 is due to inappropriate genetic substitution.
U2 - 10.1093/genetics/162.1.259
DO - 10.1093/genetics/162.1.259
M3 - Journal article
C2 - 12242238
AN - SCOPUS:0036742535
VL - 162
SP - 259
EP - 271
JO - Genetics
JF - Genetics
SN - 0016-6731
IS - 1
ER -