stn, stoned, l(1)X-3, X-3, X3
Gene model reviewed during 5.53
gene_with_dicistronic_mRNA ; SO:0000722
Gene model reviewed during 5.52
Gene model reviewed during 5.54
8.4 (northern blot)
850 (aa); 145 (kD observed)
Although the predicted molecular weight of the
stnA protein is 93 kD, its apparent molecular weight is 145 kD. The
stnA fusion protein also exhibited lower than expected mobility on
Under reducing SDS-PAGE conditions, the stnA protein migrates at 70kD.
The stnA protein is highly acidic, and contains no cysteine or internal
Interacts with the second C2 domain of Syt.
The Asp-Pro-Phe (DPF) motifs, which are found in many presynatic proteins, are thought to mediate an interaction with AP-2alpha.
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\stnA using the Feature Mapper tool.
GBrowse - Visual display of RNA-Seq signalsView Dmel\stnA in GBrowse 2
Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see GBrowse for alignment of the cDNAs and ESTs to the gene model.
For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.
Rescue analysis suggests that the stnB open reading frame (ORF) encodes all vital and important functions of the dicistronic "stn" locus and that the stnA ORF encodes a dispensible protein. However, this interpretation is limited by the absence of a true null for "stn" due to partial rescue of presynaptic stnA protein by transgenically provided stnB protein.
Neuronal expression of a dicistronic "stn" transcript (encoding both stnA and stnB proteins) is sufficient to rescue various phenotypic defects of "stn" mutants, including lethality and defects in evoked transmitter release and syt protein localisation at the nerve terminals. In addition, neural expression of a monocistronic stnB transgene is sufficient to rescue all these defects. In contrast, neural expression of a monocistronic stnA transgene does not rescue any of the "stn" mutant phenotypes. In addition, "stn" is required for regulating normal growth and morphology of the motor terminal, and this function is also provided by a monocistronic stnB transgene.
"stn" mutants show a striking decrease in the size of the endo-exo-cycling synaptic vesicle pool and loss of spatial regulation of the vesicular recycling intermediates. Mutant synapses display a significant delay in vesicular membrane retrieval after depolarisation and neurotransmitter release.
The 'stoned' locus produces a dicistronic transcript and encodes two distinct polypeptides.
The stnA gene product interacts directly or indirectly with the cAMP second messenger system, synaptic membrane recycling pathway and with biogenic amine metabolism.
stnA functions either in the nervous system or in both the nervous system and the musculature, but is not required for gross neural development. Mutations at stnA show allele-specific interactions with mutations at dnc and shi.
Exists as temperature-sensitive behavioral, temperature-sensitive lethal, and unconditionally lethal alleles. Combining stnA with t, which by itself leads to decreased amplitude of ERG on and off transients, leads to loss of anomalous jumping and partial restoration of light-off spike.