Xenbase Image ID: 79870

FIG. 5. XCdc42 affects convergent extension, but not mesoderm induction. (A) Embryos were injected as indicated into the animal pole of four blastomeres at the four-cell stage. Animal cap explants were excised at stage 8.5, treated with 10 ng/ml recombinant activin, and cultured to the equivalent of stage 18. (a) Animal cap explants from uninjected control embryos elongated significantly in response to activin. (b) WT XCdc42 mRNA (400 pg) injection interfered with activin-induced explant elongation. (c) Animal cap explants injected with DN XCdc42 mRNA (2 ng) failed to elongate. (d) Coinjection of WT XCdc42 mRNA (400 pg) together with DN XCdc42 mRNA (400 pg) rescued the elongation of animal caps. (B) Injections were targeted to the DMZ at the four-cell stage. DMZ explants were excised at stage 10 and cultured to stage 20 before being measured for elongation. (a) Uninjected control DMZ explants elongated significantly. Injection of either (b) WT XCdc42 (400 pg) or (c) DN XCdc42 (2 ng) suppressed convergent extension of DMZ explants. (C) Quantitation of convergent extension of animal cap (AC) and DMZ explants. RNAs expressed are shown below graph. n, total number of explants. (D) RT-PCR analysis detecting expression of mesodermal markers in animal caps derived from embryos injected with XCdc42 constructs. Animal caps from embryos injected with either WT XCdc42 (400 pg) alone or WT and DN XCdc42 (400 pg each) were treated with activin at stage 8.5 and cultured until stage 10.5 for analysis of goosecoid (gsc), Xbra, and chordin (Chd) expression and until stage 23 for analysis of muscle actin (M. actin) expression. ODC and EF-1alpha are loading controls. Image published in: Choi SC and Han JK (2002) Copyright © 2002. Image reproduced with permission of the Publisher, Elsevier B. V. Larger Image Printer Friendly View

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