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Figure 5
Fibronectin is required for inter-tissue adhesion and a hsp70: fn1a-mKIKGR transgene rescues fn1a -/-; fn1b-/- double mutants.
(A–B) fn1a -/-; fn1b-/- double mutants exhibit a precociously converged neural tube and tissue detachment similar to MZ itgα5-/- mutants. (A) Transverse section 160 μm from last somite boundary in 12–14 somite stage fn1a-/-; fn1b -/- embryos with labeled nuclei (red) and F-actin (green). Dotted line delineates the neural tube. Arrowhead indicates tissue detachment. Scale bar = 70 μm. (B) Quantification of the medial-lateral length of the neural tube along the anterior-posterior axis starting from the last somite boundary (0 μm). Data represent means and SD. Immunostaining for Fibronectin (FN) on a 24 hpf heat shocked sibling (C), a non-heat shocked fn1a -/-; fn1b -/-; Tg hsp70: fn1a-mKIKGR embryo (D) and a heat shocked fn1a -/-; fn1b -/-; Tg hsp70: fn1a-mKIKGR embryo (E). Lateral views of the trunk with anterior to the left. DIC images of a heat shocked sibling (F), a non-heat shocked fn1a -/-; fn1b-/-; Tg hsp70: fn1a-mKIKGR embryo (G) and a heat shocked fn1a -/-; fn1b -/-; Tg hsp70: fn1a-mKIKGR embryo (H).