Exon 2 of the mouse Syt11 (synaptotagmin XI) gene carries a Flag tag insertion and is flanked by loxP sites in this Syt11 knock-in allele. Cre recombinase-mediated excision of the floxed exon results in a knock-out of the gene, useful in studies of neurotransmitter release mechanisms.
Dr. Thomas C. Sudhof, Stanford University School of Medicine
Synaptotagmin XI (encoded by Syt11) is a synaptotagmin isoform that lacks an apparent ability to bind calcium, phospholipids, or SNARE proteins. SYT11 protein resides on abundant vesicles that differ from synaptic vesicles and resemble trafficking endosomes. These vesicles recycle via the plasma membrane in an activity-dependent manner, but their exocytosis is slow and desynchronized. Knock-outs of the gene are lethal.
Exon 2 of the mouse Syt11 gene carries a Flag tag insertion and is flanked by loxP sites in this Syt11 knock-in allele. Mutant protein levels are similar to those of the wildtype protein and expression is brain-specific, localized in the neuronal soma and dendrites.
Cre recombinase-mediated excision of the floxed exon results in a knock-out allele useful in studies of neurotransmitter release mechanisms. Selective ablation of Syt11 in excitatory forebrain neurons (via crosses with a Nex:Cre (Neurod6tm1(cre)Kan) strain which drives recombination in differentiating neurons as early as embryonic day 11.5) does not affect life span but impairs synaptic plasticity and memory. SYT11-deficient neurons display normal secretion of fast neurotransmitters and peptides but exhibit a reduction of long-term synaptic potentiation.
An FRT-neomycin-FRT-loxP cassette was placed in intron 1, a reporter tag composed of two Flag epitopes and a tetracysteine motif (DYKDDDDKCCPGCCDYKDDDDK) was inserted in-frame into exon 2, and a loxP site was place in intron 2 via homologous recombination in (129X1/SvJ x 129S1/Sv)F1- Kitl+-derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts. Resultant mice were crossed with a Flp recombinase-expressing strain to excise the neomycin cassette, leaving Flag-tagged exon 2 flanked by loxP sites. This strain was backcrossed to C57BL/6 once, and maintained on a mixed C57BL/6 and 129 background by the donating laboratory.
|Allele Name||targeted mutation 1, Thomas C Sudhof|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Syt11, synaptotagmin XI|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||A targeting vector was designed to place a LoxP-Flp-neomycin-Flp cassette in intron 1, a FLAG-(C)4-FLAG cassette in exon 2, and LoxP site in intron 2. Mutant protein expression levels are similar to those of the wildtype protein. Expression is brain-specific and localized in the neuronal soma and dendrites (presumably on cargo vesicles). Protein can be recognized using FLAG antibody by Western blot analysis, but not in brain sections and labeled cultures. No significant N-ethyl-maleimide-sensitive factor attachment protein receptor (SNARE) binding is observed in immunoprecipitation (IP) assays.|
|Mutations Made By|| |
Dr. Thomas Sudhof, Stanford University School of Medicine
Heterozygotes and homozygotes are viable and fertile.
When using the Syt11 knock-in, 11E mouse strain in a publication, please cite the originating article(s) and include JAX stock #008294 in your Materials and Methods section.