Generation and characterization of Ins1-cre-driver C57BL/6N for exclusive pancreatic beta cell-specific Cre-loxP recombination.
Cre/loxP system-mediated site-specific recombination is utilized to study gene function in vivo. Successful conditional knockout of genes of interest is dependent on the availability of Cre-driver mice. We produced and characterized pancreatic β cell-specific Cre-driver mice for use in diabetes mellitus research. The gene encoding Cre was inserted into the second exon of mouse Ins1 in a bacterial artificial chromosome (BAC). Five founder mice were produced by microinjection of linearized BAC Ins1-cre. The transgene was integrated between Mafa and the telomere on chromosome 15 in one of the founders, BAC Ins1-cre25. To investigate Cre-loxP recombination, BAC Ins1-cre25 males were crossed with two different Cre-reporters, R26R and R26GRR females. On gross observation, reporter signal after Cre-loxP recombination was detected exclusively in the adult pancreatic islets in both F1 mice. Immunohistological analysis indicated that Cre-loxP recombination-mediated reporter signal was colocalized with insulin in pancreatic islet cells of both F1 mice, but not with glucagon. Moreover, Cre-loxP recombination signal was already observed in the pancreatic islets at E13.5 in both F1 fetuses. Finally, we investigated ectopic Cre-loxP recombination for Ins1, because the ortholog Ins2 is also expressed in the brain, in addition to the pancreas. However, there was no Cre-loxP recombination-mediated reporter signal in the brain of both F1 mice. Our data suggest that BAC Ins1-cre25 mice are a useful Cre-driver C57BL/6N for pancreatic β cell-specific Cre-loxP recombination, except for crossing with knock-in mice carrying floxed gene on chromosome 15.
Laborarory Animal Resource Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan.
Yoshikazu
Y
Hasegawa
Yoko
Y
Daitoku
Seiya
S
Mizuno
Yoko
Y
Tanimoto
Saori
S
Mizuno-Iijima
Miki
M
Matsuo
Noriko
N
Kajiwara
Masatsugu
M
Ema
Hisashi
H
Oishi
Yoshihiro
Y
Miwa
Kazuyuki
K
Mekada
Atsushi
A
Yoshiki
Satoru
S
Takahashi
Fumihiro
F
Sugiyama
Ken-ichi
K
Yagami
D000818:Animals; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D003920:Diabetes Mellitus / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D005260:Female; D007328:Insulin / Q000235:genetics*; D050417:Insulin-Secreting Cells; D019426:Integrases / Q000235:genetics*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic / Q000235:genetics*; D008249:Protein-Lysine 6-Oxidase / Q000235:genetics*; D011995:Recombination, Genetic / Q000235:genetics*
D016326:Extracellular Matrix Proteins; C514817:Ins1 protein, mouse; D007328:Insulin; C077112:Lox protein, mouse; D008249:Protein-Lysine 6-Oxidase; C045073:Cre recombinase; D019426:Integrases