February&March 2013 Cre reporter mouse expressing nuclear-localized beta-galactosidase

Cre reporter mouse expressing nuclear-localized
beta-galactosidase

B6.129P2-Gt(ROSA)26Sor<tm1(NLS-lacZ)Ito>/ItoRbrc RBRC02657

Courtesy of Dr. Shigeyoshi Itohara, RIKEN BSI

Cre recombinase is a 38-kDa enzyme derived from bacteriophage P1 that specifically recognizes 34-bp loxP sites. Cre is among the most widely used site-specific recombinases in genome engineering. For identifying the derivatives of Cre-expressing cells, a number of reporter mouse strains have been reported, such as ROSA26 reporter mice (R26R mice) [1]. One potential disadvantage of these Cre reporter mice is that analysis at the level of single cells can be difficult or imprecise in neuronal tissue (e.g., cerebral cortex and thalamus), due to diffuse signals in the cell cytoplasm after staining.

Dr. Itohara and colleagues targeted the ROSA26 locus to generate new reporter mice (R26-NLS-lacZor RNZ mice) in which lacZ including the SV40 nuclear localization signal (NLS) was inserted downstream of the loxP-flanked PGK-neo cassette [2]. The left two panels show X-gal staining of coronal brain sections from Emx1-Cre/R26R mice. Cre-mediated recombination in Emx1-Cre mice (RBRC01345) is reportedly specific to excitatory cortical neurons [3, 4]. The two right panels show sections from Emx1-Cre/RNZ mice, indicating that RNZ reporter mice expressing nuclear-localized beta-galactosidase allow for single-cell resolution. The new RNZ mice are useful as a Cre reporter strain following Cre-mediated recombination.

Depositor

Dr. Shigeyoshi Itohara
Laboratory for Behavioral Genetics, RIKEN Brain Science Institute

References

[1]	Soriano P. Generalized lacZ expression with the ROSA26 Cre reporter strain. Nat Genet.; 21(1):70-1, 1999.
[2]	Kobayashi Y, Sano Y, Vannoni E, Goto H, Suzuki H, Oba A, Kawasaki H, Kanba S, Lipp H-P, Murphy NP, Wolfer DP, Itohara S. Genetic dissection of medial habenula-interpeduncular nucleus pathway function in mice. Front Behav Neurosci.; 7: 17, 2013.
[3]	Iwasato T, Datwani A, Wolf AM, Nishiyama H, Taguchi Y, Tonegawa S, Knöpfel T, Erzurumlu RS, Itohara S. Cortex-restricted disruption of NMDAR1 impairs neuronal patterns in the barrel cortex. Nature; 406(6797):726-31, 2000.
[4]	Iwasato T, Nomura R, Ando R, Ikeda T, Tanaka M, Itohara S. Dorsal telencephalon-specific expression of Cre recombinase in PAC transgenic mice. Genesis; 38(3):130-8, 2004.

Comments are closed.