Xenbase Image ID: 76980

Fig. 7. The RA and Fgf pathways regulate each other. The levels of RA signalling (AI) were altered by addition of a synthetic RA antagonist (left column) or all-trans RA (right column) and compared to a DMSO control (centre column). Embryos were assayed for fgf4 (AC) and fgf8 (DI) expression. The posterior domain of fgf4 (a) is lost in RA treated embryos (C) when compared to the control (B), but unaffected in embryos treated with RAA. Expression of fgf8 is expanded both anteriorly (E and F) and posteriorly (H and I; compare distance between arrowheads (d) marking the anterior limits of domain, and (e) marking posterior limits of domain) under treatment with RA. Decreasing RA signalling also reduces the anterior domain of fgf8 underlying the heart region (compare ratio of staining intensity between (b) marking the pituitary anlagen to (c)). A similar effect is seen with sprouty2 expression (JO), as its domain is increased with RA in both the anterior heart region (L; arrowhead f) and it extends further anterior (g) in the dorsal neural tube (O) when compared to controls (KN). Conversely, embryos were treated with SU5402 and assayed for expression of aldh1a2 (P and Q) or cyp26 (R and S) to determine the effect of a loss of Fgf signalling on the RA signalling pathway. The expression domain of aldh1a2 was expanded posterior (Q) (arrowhead: h marking posterior limit of expression domain) as compared to control embryos (P). Cyp26, normally present in the posterior LPM tailbud domain (R; arrowhead i) is undetectable when Fgf signalling is inhibited (S). Ant: anterior view with dorsal at top of image. Dor: dorsal view with anterior at top. Llv: left lateral view with anterior toward left, dorsal at top of image. Pos: posterior view with dorsal at top. The total number of embryos examined for each panel is indicated in the lower left hand corner. Image published in: Deimling SJ and Drysdale TA (2011) Copyright © 2011. Image reproduced with permission of the Publisher, Elsevier B. V. Gene Synonyms Species Stage(s) Tissue fgf4.L efgf, fgf-4, fgf4-a, fgf4-b, fgfe, HBGF-4, XEFGF, Xfgf-4, Xfgf4 X. laevis Throughout NF stage 18 to NF stage 20 involuted dorsal mesoderm paraxial mesoderm fgf8.L AIGF, FGF-8, fgf-8b, fgf8a, fgf8b, MGC79739, Xfgf-8, Xfgf8 X. laevis Sometime during NF stage 18 to NF stage 20 preplacodal ectoderm presumptive midbrain-hindbrain boundary anterior neural ridge neural tube posterior neural tube spry2.S sprouty 2, sprouty-2, sprouty2, Xsprouty2, xspry2, Xtsprouty2 X. laevis Sometime during NF stage 18 to NF stage 20 presumptive midbrain-hindbrain boundary anterior neural ridge preplacodal ectoderm neuroectoderm neural tube neural fold aldh1a2.L raldh-2, raldh2, XRaldh2 X. laevis Sometime during NF stage 18 to NF stage 20 lateral plate mesoderm dorsal lateral plate mesoderm anterior dorsal lateral plate region optic vesicle cyp26a1.L cyp26, RACE, retinoic acid converting enzyme, xCYP26, XCYP26A1 X. laevis Sometime during NF stage 18 to NF stage 20 mesoderm axial mesoderm paraxial mesoderm posterior Image source: Published Experiment + Assay Source Phenotypes and Disease Xla Wt + Retinoic acid + NF18-20 (in situ hybridization) Fig 7 ADGJM (c1) Expression Phenotype increased amount fgf8.L expression in anterior neural tube decreased amount fgf8.L expression in anterior placodal area increased amount fgf8.L expression in posterior neural tube Xla Wt + retinol + NF18-20 (in situ hybridization) Fig. 7 CFILO Expression Phenotype absent fgf4.L expression in presumptive paraxial mesoderm decreased amount fgf8.L expression in adenohypophyseal placode absent fgf8.L expression in anterior neural tube decreased amount fgf8.L expression in anterior placodal area increased amount fgf8.L expression in posterior neural tube absent fgf8.L expression in presumptive midbrain-hindbrain boundary decreased amount spry2.L expression in cardiac mesoderm increased amount spry2.L expression in neural tube Larger Image Printer Friendly View

Return to previous page