Expression patterns of engrailed‐like proteins in the chick embryo

Abstract

The protein products of both of the identified chick engrailed-like (En) genes, chick En-1 and chick En-2, are localized in cells of the developing brain, mandibular arch, spinal cord, dermatome, and ventral limb bud ectoderm, as demonstrated by labeling with the polyclonal antiserum cuEnhb-1 developed by Davis et al. (Development 111:281-298, 1991). A subpopulation of cephalic neural crest cells is also En-protein-positive. The monoclonal antibody 409 recognizes the chick En-2 gene product exclusively (Patel et al.: Cell 58:955-968, 1989;Davis et al., 1991) and colocalizes with chick En-2 mRNA in the developing head region of the chick embryo as shown by in situ hybridization (Gardner et al.: J. Neurosci. Res. 21:426-437,1988). In the present study we examine the pattern of d n h b -1 and 409 localization throughout the chick embryo from the first appearance of antibody (Abbpositive cells at stage 8 (Hamburger and Hamilton: J. Morphol. 88:49-92, 1951) through stage 28 (1-5.5 days). We compare the localization patterns of the two Abs to each other, as well as to the localization of the monoclonal Ab, HNK-1, which recognizes many neural crest cells, using double-and triple-label fluorescence immunohistochemistry. Most En proteinpositive cells in the path of neural crest cell migration are not HNK-1 positive. In detailed examination of d n h b -1 and 409 localization, we find previously undetected patterns of En protein localization in the prechordal plate, hindbrain, myotome, ventral body-wall mesoderm, and extraembryonic membranes. Based upon these observations we propose: 1) that En expression in the mesoderm may be induced through interaction with En expressing cells in the neuroectoderm; 2) that En expression in the head mesenchyme is associated with somitomere 4; and 3) that En expression may be involved in epithelial-mesenchymal cell transformations.Q 1992 Wiley-Liss, Inc.

Engrailed protein is expressed in interneurons but not motor neurons of the dorsal unpaired median group in the adult grasshopper

“…In vertebrates, by contrast, En expression occurs regionally, in a fashion that is difficult to reconcile with the segmental model (Patel et al, 1989). En gene expression in vertebrates has a complex and changing pattern during embryonic and postembryonic morphogenesis in mesodermal and ectodermally derived tissues (Davis et al, 1988(Davis et al, , 1991Gardner et al, 1989;Hatta et al, 1991;Gardner and Barald, 1992). Consistent with a broad function, En-1 knockout mice have multiple developmental defects, including loss of much of the cerebellum and colliculi, truncation and duplication of digits, and defects of sternum and ribs (Wurst et al, 1994).…”

The Ghost of Selection Past: Rates of Evolution and Functional Divergence of Anciently Duplicated Genes

“…Force et al (1999) showed that this might be the case for the En1 genes in zebrafish. In mouse and chicken, En1 is expressed in the developing pectoral appendage bud and in specific neurons of the hindbrain and spinal cord (Joyner and Martin 1987;Davis et al 1991;Gardner and Barald 1992). In zebrafish, however, one of the paralogs is expressed in the pectoral appendage bud, while the second paralog is expressed in the hindbrain/spinal cord neurons (Force et al 1999).…”

Untitled

“…Force et al (1999) showed that this model might generally apply based on the En1 genes in zebrafish. In mouse and chicken, En1 is expressed in the developing pectoral appendage bud and in specific neurons of the hindbrain and spinal cord (Joyner and Martin, 1987;Davis et al, 1991;Gardner and Barald, 1992). In zebrafish, however, one of the paralogs is expressed in the pectoral appendage bud, while the second paralog is expressed in the hindbrain/spinal cord neurons (Force et al, 1999).…”