Investigation of the fate of Sry-expressing cells using an in vivo Cre/loxP system.
Sry (sex-determining region on Y chromosome) is expressed in the undifferentiated, bipotential genital ridges of mammalian XY fetuses. The expression of Sry initiates testis development, but the lineage of Sry-expressing cells is unclear. In this study, double-transgenic mice were analyzed using the Cre/loxP system. Cre under the control of the Sry promoter was expressed in the fetal gonads of transgenic mice similarly to endogenous Sry. The Sry/Cre-transgenic mice were crossed with CAG(cytomegalovirus immediate-early enhancer, chicken beta-actin promoter and fusion intron of chicken beta-actin and rabbit beta-globin)/loxP/CAT/loxP/LacZ-transgenic mice, in which the transgene expressed beta-galactosidase after a Cre-mediated recombination event. Sertoli cells, germ cells of testes and granulosa cells of ovaries of double-transgenic mice stained positive with X-gal. Cre expression was detected in germ cells and peritubular/Sertoli cells in adult testes. It is not clear whether beta-galactosidase expression in the Sertoli cells of the testes occurred as a result of Cre expression in the adult or in the fetal gonads. These analyses indicate that cells expressing Sry-inducing factors in female fetal gonads become granulosa cells.
Ito
Masanori
M
Laboratory of Applied Genetics, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Japan. mito@tmh.tmc.edu
Yokouchi
Kou
K
Yoshida
Kazuhisa
K
Kano
Kiyoshi
K
Naito
Kunihiko
K
Miyazaki
Jun-Ichi
J
Tojo
Hideaki
H
D000818:Animals; D019070:Cell Lineage / Q000235:genetics; D002478:Cells, Cultured; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006107:Granulosa Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D019426:Integrases / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D010053:Ovary / Q000166:cytology / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011817:Rabbits; D011995:Recombination, Genetic; D012708:Sertoli Cells / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D051876:Sex-Determining Region Y Protein / Q000235:genetics* / Q000378:metabolism*; D013737:Testis / Q000166:cytology / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism; D001616:beta-Galactosidase / Q000032:analysis / Q000235:genetics
D051876:Sex-Determining Region Y Protein; C497746:Sry protein, mouse; D014764:Viral Proteins; C045073:Cre recombinase; D019426:Integrases; D001616:beta-Galactosidase