Isolation of an abdominal-A gene from the locust Schistocerca gregaria and its expression during early embryogenesis.
Using sequence homology to Drosophila homeobox-containing genes, we have cloned a homologue of abdominal-A from the locust Schistocerca gregaria. The Schistocerca clone encodes a stretch of 78 amino acids including the homeodomain and its flanking regions identical to the corresponding region of abdominal-A. We have shown by in situ hybridization that this gene is transcribed and have used an antibody raised against its protein product to examine the expression of abdominal-A during early Schistocerca embryogenesis. Schistocerca is a short germ insect. Although the segmented body plan is very similar to that of Drosophila, the segments are generated sequentially by a process of growth, not simultaneously by subdivision of a syncytial blastoderm. In both organisms, abdominal-A is expressed throughout the abdomen from a sharp anterior boundary located within the first abdominal segment (A1). The initial activation of the genes in the two species differs. Schistocerca initiates expression in a small group of cells in the anterior of A2, shortly after this segment is defined by the appearance of engrailed protein. This contrasts with the appearance of abdominal-A expression in Drosophila, which appears simultaneously throughout the entire abdomen.
Tear
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Department of Genetics, Cambridge University, UK.
Akam
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Martinez-Arias
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A
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015870:Gene Expression / Q000235:genetics*; D005801:Genes, Homeobox / Q000235:genetics*; D006110:Grasshoppers / Q000196:embryology / Q000235:genetics*; D008969:Molecular Sequence Data