Heterogeneous inducible mammary-specific expression of Jab/SOCS1 in lactating transgenic mice is associated with no obvious phenotype, even at the cellular level.
The cytokine-inducible suppressor of cytokine signalling SOCS1, or JAB, has been shown to be implicated in vitro in the negative regulation of the prolactin-receptor-induced activation of JAK2 and STAT5. Disruption of this gene in vivo resulted in an accelerated mammary gland development. In the present experiment, we assessed the potential impact on the lactation process of the doxycycline-inducible mammary-controlled expression of this gene in transgenic mice. Three transgenic mouse lines that expressed JAB specifically in the mammary gland in a conditional manner following doxycycline treatment were successfully established. The resulting overall expression of JAB was high and ranged from half to four times that of the endogenously expressed homologous gene in the thymus. It was found to be highly heterogeneous in the mammary epithelium, with less than 5% of JAB-expressing cells detected. Phenotypic analysis of these transgenic mice exhibiting doxycycline-induced JAB expression did not reveal any obvious effect on the lactation process. Double immunostaining experiments suggested that JAB expression in vivo did not significantly affect the beta-casein gene expression and the STAT5a nuclear localisation. These results do not support a role for JAB in the disruption of the lactation process.
Petridou
Barbara
B
Génomique et Physiologie de la Lactation, Institut National de la Recherche Agronomique, 78352 Jouy-en-Josas Cedex, France. Petridou@diamant.jouy.inra.fr
Soulier
Solange
S
Besnard
Nathalie
N
Hudrisier
Marthe
M
Hue-Beauvais
Catherine
C
Costa Da Silva
José
J
Djiane
Jean
J
Vilotte
Jean-Luc
JL
D000818:Animals; D016466:CHO Cells; D002352:Carrier Proteins / Q000378:metabolism*; D006224:Cricetinae; D003412:Cricetulus; D005260:Female; D007150:Immunohistochemistry; D007774:Lactation; D008321:Mammary Glands, Animal / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D008894:Milk Proteins / Q000378:metabolism; D010641:Phenotype; D011247:Pregnancy; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D019076:Transgenes
D002352:Carrier Proteins; D008894:Milk Proteins; D012097:Repressor Proteins; C491590:Socs1 protein, mouse; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins