To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Play VideoPlayMuteCurrent Time 0:00/Duration Time 0:00Loaded: 0%Progress: 0%Stream TypeLIVERemaining Time -0:00 Playback Rate1ChaptersChaptersdescriptions off, selectedDescriptionssubtitles off, selectedSubtitlescaptions off, selectedCaptionsAudio TrackFullscreenThis is a modal window. Captions Settings Dialog Beginning of dialog window. Escape will cancel and close the window. Text Color White Black Red Green Blue Yellow Magenta Cyan Transparency Opaque Semi-Opaque Background Color Black White Red Green Blue Yellow Magenta Cyan Transparency Opaque Semi-Transparent Transparent Window Color Black White Red Green Blue Yellow Magenta Cyan Transparency Transparent Semi-Transparent Opaque Font Size 50% 75% 100% 125% 150% 175% 200% 300% 400% Text Edge Style None Raised Depressed Uniform Dropshadow Font Family Proportional Sans-Serif Monospace Sans-Serif Proportional Serif Monospace Serif Casual Script Small Caps Defaults Done Movie 2 Contraction of adult cKO seminiferous tubule Development ; doi: 10.1242/dev.185884 Download Original Video