Figure 2.
Inhibition of mir-125a-5p perturbs somitogenesis in chicken embryos, and stabilizes Lfng transcripts in the PSM A. Electroporation of anti-NC#1MO has no effect on somite morphology (panel a), while electroporation of anti-mir-125aMO results in abnormal somite morphology with absent (dashed line) or disorganized (arrows) intersomitic boundaries in electroporated regions (panel b).B. Uncx4.1 staining is reduced and diffuse in embryos electroporated with anti-mir-125aMO (dashed line, panel b) compared to anti-NC#1MO (panel a). Note relatively normal somites in the older region of the anti-mir-125aMO embryo in the region that is less positive for the morpholino (square bracket). The same embryo is pictured in part A panel a and part B panel a C. MyoD expression is disorganized in somites electroporated with anti-mir-125aMO (dashed line, panel b) compared to embryos electroporated with anti-NC#1MO (panel a). Note normal myotomes in the unelectroporated regions of the anti-mir-125aMO embryo (square brackets). D 2h post-electroporation with anti-NC#1MO, endogenous Lfng is observed in the three described phases (Pourquie and Tam, 2001). In contrast, in anti-mir-125aMO positive embryos, robust, non-cyclic Lfng expression is observed in the caudal PSM of all embryos (panel d, n=15/15). E In situ analysis with a probe specific for the Lfng intron demonstrates that both control embryos (a,b) and embryos electroporated with anti-mir-125aMO (c,d) exhibit dynamic patterns of newly transcribed Lfng RNA. F. c-hairy1 expression is cyclic in control embryos (a-c), or in embryos electroporated with anti-mir-125aMO (d-f)Right hand panels reflect the fluorescein signal demarcating the electroporated regions of each embryo. Fl: fluorescein. Degree of electroporation efficiency designated as “++ ” = strong, “+” = moderate, “(+)” = weak,“ −” = negative. Arrowheads indicate the most recent somite boundary. See figure S2 for fluorescein images as well as analysis of mir-125a-5p by in situ in electroporated embryos.