Ectopic expression of a genomic fragment containing a homeobox causes neural defects in the axolotl.
An axolotl (Ambystoma mexicanum) genomic fragment containing the Ahox1 homeobox was placed under the control of the mouse hsp68 promoter, which seems to function constitutively in the axolotl. The resulting construct was injected into fertilized axolotl eggs to see if it would perturb development. Of the injected embryos, 20% showed severe reduction of the anterior neural plate. Later in development, these embryos had small heads, no eyes, and appeared to lack the normal regionalization of the brain. An additional 35% of the embryos were less severely affected, but had reduced or missing eyes. Control embryos, including ones injected with a construct missing the DNA recognition helix of the homeobox, developed normally.
Department of Biology, University of Ottawa, Ont., Canada.
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M
Whiteley
J B
JB
Armstrong
D000557:Ambystoma; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002490:Central Nervous System / Q000196:embryology*; D005314:Embryonic and Fetal Development; D005260:Female; D005306:Fertilization; D015870:Gene Expression; D005801:Genes, Homeobox; D008845:Microinjections; D008969:Molecular Sequence Data; D010957:Plasmids; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic