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Figure 5.
E2a Fused to the Engrailed Repressor Domain Causes Mild Blastopore Formation Defects and Loss of Axial Mesoderm and Synergizes with Low Doses of lefty mRNA
(A) Effects of E2a-EnR injection (both cells at the two-cell stage) at stage 11. Embryos injected with E2a-EnR have delayed blastopore closure relative to uninjected control embryos but far better blastopore formation than E2a morphants. Stage 10.5 E2a-EnR embryos express more xbra than E2a morphants but less than control embryos. E2a-EnR-injected embryos express less lefty than E2a morphants.
(B) Effects of E2a-EnR injection (both cells at the two-cell stage) at stage 30. E2a-EnR-injected embryos show reduced expression of muscle markers (myoD, myf5) and notochord markers (shh, foxA2) but normal expression of the heart marker nkx2.5.
(C) E2a-Enr and 5 pg of lefty mRNA each cause only modest effects on blastopore closure, but embryos injected with both mRNAs show a failure of bottle cell formation similar to E2a morphants. Arrowhead indicates bottle cells. |
