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Updated: Jun 23, 2026

Using Ex Vivo Upright Droplet Cultures of Whole Fetal Organs to Study Developmental Processes during Mouse Organogenesis
Published on: October 21, 2015
Morphometric analysis of testis cord formation in Sox9-EGFP mice
Liesl Nel-Themaat1, Tegy J Vadakkan, Ying Wang
1Department of Genetics, University of Texas, M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Abstract:
Sox9-EGFP knockin mice were generated to label Sertoli cells and visualize testis cord formation during development. Confocal microscopy and morphometric analysis of developing cords were performed. Serial histological sections were used for three-dimensional cord reconstruction. Initially, gonad length decreased from embryonic day (E) 11.5 to E13.5, but increased thereafter, while gonad width doubled every 12 hours from E11.5 through E14.5. At E12.5, the average number of cords was 12.5, whereas this decreased to 10.4 at E13.5 and E14.5. Cord number at a given time point varied between gonads and influenced dimensions. The initial cords that formed were complex and branches were common. Time-lapse imaging revealed an intricate behavior of the Sertoli-germ cell mass and cellular exchange between connected neighboring cords. These results suggest that cord formation is a highly dynamic process that subsequently becomes refined to establish the final number of seminiferous tubule precursors.
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