Cx43 gap junction gene expression and gap junctional communication in mouse neural crest cells

Abstract

Although gap junctions are not known to be important in mediating cell‐cell interactions amongst migratory cells, our studies showed that the connexin 43 (Cx43) gap junction gene is widely expressed in mouse neural crest cell lineages. Using in situ hybridization analysis, Cx43 expression was detected in presumptive neural crest cells emerging from the neural folds of the early postimplantation embryo. Neural crest expression of the Cx43 gap junction gene was also indicated by the analysis of transgenic mice containing a lacZ reporter construct driven by the Cx43 promoter. In neural tube explant cultures of these transgenic mice, lacZ expression was observed in the emerging neural crest outgrowths. Whole mount X‐gal staining of these transgenic embryos at various stages of development showed lacZ expression in neural crest cells distributed along the entire craniocaudal axis, with expression found in both cranial and trunk neural crest cells contributing to a wide range of embryonic tissues. This included presumptive cardiac neural crest cells localized in the heart. In light of the widespread expression of Cx43 in neural crest cell lineages, dye injection studies were carried out to determine if neural crest cells are functionally coupled via gap junctions. Such studies revealed extensive dye coupling among presumptive neural crest cells, thus demonstrating that these migratory cells are indeed gap junctional communication competent. In total, these observations suggest that gap junctions may play a role in mouse neural crest development. This possibility is particularly intriguing given the recent finding that the Cx43 knockout mice die of defects associated with the outflow tract [Reaume et al., 1995], a region of the heart in which neural crest cells are required for normal development. Dev. Genet. 20: 119–132, 1997. © 1997 Wiley‐Liss, Inc.

Differential Expression of Connexin43 and Desmin Defines Two Subpopulations of Medial Smooth Muscle Cells in the Human Internal Mammary Artery

“…35 Cx43 is highly expressed by the neural crest cell lineage and is associated with the development of proximal great vessels. 42 The inverse relationship between Cx43 and desmin expression in the internal mammary artery is not only a feature of whole groups of cells; data from preliminary double-label experiments on cultured cells indicate that the relationship applies at the level of the individual cell (Y.-S.K.) (unpublished data, 1998).…”

Microarray analysis of homocysteine‐responsive genes in cardiac neural crest cells in vitro

“…Our choosing the explanted neural tube as a source of neural crest cells is based upon previous work that demonstrated significant changes in the behavior of neural crest cells treated with homocysteine (e.g., Brauer and Rosenquist, 2002). The neural tube has been used as the source of migratory neural crest cells in vitro in experiments with other vertebrates as well, including the mouse (e.g., Lo et al, 1997;Bannerman et al, 2000;Epstein et al, 2000) and the axolotl (e.g., Cerny et al, 2005). Other laboratories have obtained migratory neural crest cells from isolated neural folds (Basch et al, 2000) or branchial arches (Zhao et al, 2006); however, there is no universally accepted standard model for studying neural crest cells in vitro, and our having chosen the neural tube explant model makes the present results more comparable with our earlier work.…”

Primordial germ cell migration

“…Junctions between neural-crest cells are thought to allow cell-cell communication during the migration process (Lo et al, 1997). Loss of the gap-junction protein Cx43 interferes with neural crest migration (Xu et al, 2001).…”