Mouse homeobox gene transcripts occupy different but overlapping domains in embryonic germ layers and organs: a comparison of Hox-3.1 and Hox-1.5.
By use of in situ hybridization experiments, the mouse homeobox genes Hox-3.1 and Hox-1.5 are compared in the temporal and spatial patterns of their embryonic transcripts. Transcripts of both genes are first detected at about 7 1/2 days, although the appearance of Hox-3.1 transcripts apparently follows Hox-1.5 after a small delay. Hox-3.1 and Hox-1.5 transcripts occupy domains which are different, although overlapping, along the anteroposterior axis of the embryo. The domains are first established within the ectoderm and mesoderm germ layers at 7 1/2-8 days, but subsequently they persist within the nervous system, the prevertebral column and within at least some of the organs (the thyroid, lung, stomach, mesonephric and metanephric kidneys) at 12 1/2 days. In discussion, two different mechanisms are considered by which positional information might first be generated within the germ layers.
Gaunt
S J
SJ
Department of Molecular Embryology, AFRC Institute of Animal Physiology and Genetics Research, Cambridge, UK.
D000818:Animals; D001345:Autoradiography; D004622:Embryo, Mammalian / Q000502:physiology*; D005314:Embryonic and Fetal Development; D005786:Gene Expression Regulation; D005801:Genes, Homeobox; D051379:Mice; D009024:Morphogenesis; D013997:Time Factors; D014158:Transcription, Genetic