These transgenic mice ("SLICK" for single-neuron labeling with inducible Cre-mediated knock-out) have a tamoxifen inducible Cre-mediated recombination system and Enhanced Yellow Fluorescent Protein driven by 2 bidirectional copies of the mouse thymus cell antigen 1 promoter. Hemizygotes are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. The Donating Investigator has not attempted to make the strain homozygous. When crossed with a strain containing a loxP site flanked sequence of interest, the offspring are useful for generating tamoxifen-induced, Cre-mediated targeted neuron-specific deletions only in neurons where the Thy1 promoter is active. These cells will be evident by the expression of Yellow Fluorescent Protein. Transgenic mice express YFP constitutively in neurons. The Donating Investigator reports that founder line A (SLICK-A) mice express the transgene in small subsets of motor neurons and dorsal root ganglion neurons.

Further characterization [Heimer-McGinn and Young 2011 genesis 49:942] reports that SLICK-A mice have high YFP fluorescence in some hippocampal regions and cortical layer V, but sparse/dim labeling in other regions (such as the midbrain and brainstem). Fluorescence is less uniform, but this allows single-neuron labeling. SLICK-A mice exhibit significant cre-mediated recombination in the absence of tamoxifen. This "leaky" recombination in SLICK-A mice was prominent in areas that have bright YFP labeling (such as hippocampal CA1 and cortical layer V). Following tamoxifen-induction, efficient recombination is observed in the expected cell types, but with some inefficient recombination observed as well (including hippocampal CA3 and cortical layers II/III). This publication concluded that YFP and cre^ERT2 expression levels are tightly coupled in SLICK-A mice, and that excessive levels of cre^ERT2 must be avoided to achieve tight control of recombinase activity when using SLICK-A mice.

The Cre-ERT2 fusion protein consists of Cre recombinase fused to a triple mutant form of the human estrogen receptor which does not bind its natural ligand (17β-estradiol) at physiological concentrations but will bind the synthetic estrogen receptor ligands 4-hydroxytamoxifen (OHT or tamoxifen) and, with lesser sensitivity, ICI 182780. Restricted to the cytoplasm, Cre-ERT2 can only gain access to the nuclear compartment after exposure to tamoxifen. To counteract the mixed estrogen agonist effects of tamoxifen injections, which can result in late fetal abortions in pregnant mice, progesterone may be coadministered.

This strain is one of many from the same transgene creator/donating investigator with fluorescent protein expression/neurobiological research applications, including:

SLICK line A (Stock No. 007606),
SLICK line V (Stock No. 007610),
SLICK line H (Stock No. 012708),
GAD67-GFP line 3 (Stock No. 007673),
Thy1-GFP line O (Stock No. 007919),
Thy1-YFP line G (line 17) (Stock No. 014130),
Thy1-CFP line I (Stock No. 014131),
Thy1-ChR2-YFP line 18 (Stock No. 007612),
Thy1-ChR2-YFP line 9 (Stock No. 007615),
Thy1-eNpHR-YFP line 2 (Stock No. 012332),
Thy1-eNpHR-YFP line 4 (Stock No. 012334),
Thy1-vChR1-YFP line 1 (Stock No. 012341),
Thy1-vChR1-YFP line 4 (Stock No. 012344),
Thy1-vChR1-YFP line 8 (Stock No. 012348),
Thy1-mhChR2-YFP line 20 (Stock No. 012350),
Prv-mhChR2-YFP line 15 (Stock No. 012355),
ChAT-ChR2-YFP line 5 (Stock No. 014545),
ChAT-ChR2-YFP line 6 (Stock No. 014546),
VGAT-ChR2-YFP line 8 (Stock No. 014548),
TpH2-ChR2-YFP line 5 (Stock No. 014555),
and R26-CAG-LSL-2XChETA-tdTomato reporter mice (Stock No. 017455).