Limits...
A novel member of the netrin family, beta-netrin, shares homology with the beta chain of laminin: identification, expression, and functional characterization.

Koch M, Murrell JR, Hunter DD, Olson PF, Jin W, Keene DR, Brunken WJ, Burgeson RE - J. Cell Biol. (2000)

Bottom Line: In addition, beta-netrin is expressed in a limited set of fiber tracts within the brain, including the lateral olfactory tract and the vomeronasal nerve.Functional studies were performed and show that beta-netrin promotes neurite elongation from olfactory bulb explants.Together, these data suggest that beta-netrin is important in neural, kidney, and vascular development.

View Article: PubMed Central - PubMed

Affiliation: Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.

ABSTRACT
The netrins are a family of laminin-related molecules. Here, we characterize a new member of the family, beta-netrin. beta-Netrin is homologous to the NH(2) terminus of laminin chain short arms; it contains a laminin-like domain VI and 3.5 laminin EGF repeats and a netrin C domain. Unlike other netrins, this new netrin is more related to the laminin beta chains, thus, its name beta-netrin. An initial analysis of the tissue distribution revealed that kidney, heart, ovary, retina, and the olfactory bulb were tissues of high expression. We have expressed the molecule in a eukaryotic cell expression system and made antibodies to the expressed product. Both in situ hybridization and immunohistochemistry were used to describe the cellular source of beta-netrin and where beta-netrin is deposited. beta-Netrin is a basement membrane component; it is present in the basement membranes of the vasculature, kidney, and ovaries. In addition, beta-netrin is expressed in a limited set of fiber tracts within the brain, including the lateral olfactory tract and the vomeronasal nerve. Functional studies were performed and show that beta-netrin promotes neurite elongation from olfactory bulb explants. Together, these data suggest that beta-netrin is important in neural, kidney, and vascular development.

Show MeSH

Related in: MedlinePlus

β-Netrin RNA appears not to be expressed in the floorplate of midgestation mouse embryos. (A and B) nonradioactive in situ hybridizations of floor- and roofplate markers (netrin-1, and wnt-1) show good localization of transcriptions to these structures, respectively. (C and D) Two different probes for β-netrin, on the other hand, fail to localize to any region in embryonic day 11.5 spinal cord; in D we see some above background reactivity in the lateral margins of the floorplate.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2192657&req=5

Figure 8: β-Netrin RNA appears not to be expressed in the floorplate of midgestation mouse embryos. (A and B) nonradioactive in situ hybridizations of floor- and roofplate markers (netrin-1, and wnt-1) show good localization of transcriptions to these structures, respectively. (C and D) Two different probes for β-netrin, on the other hand, fail to localize to any region in embryonic day 11.5 spinal cord; in D we see some above background reactivity in the lateral margins of the floorplate.

Mentions: Tissue distribution of the β-netrin protein was determined by indirect immunofluorescence in various rat tissues and the cellular sources of β-netrin were determined by in situ hybridization. One immediately obvious generalization is that β-netrin is expressed in the basement membranes of a variety of tissues (see Fig. 6Fig. 7Fig. 8Fig. 9). In the kidney (Fig. 6), β-netrin protein is expressed in the basement membranes of all tubules. The major arteries and arterioles (Fig. 6 A, arrows) were prominently reactive; also strongly reactive were the afferent arterioles (Fig. 6C and Fig. D). Particularly clear was the reactivity in the basal lamina surrounding the smooth muscle cells in the wall of the vessels. In addition, β-netrin immunoreactivity was present in the basement membrane of the rat glomerulus. This pattern of immunoreactivity is different than that reported for the laminin β2 chain (Hunter et al. 1989), further supporting a lack of cross-reactivity between these molecules. β-Netrin transcripts, as judged by in situ hybridization, are localized to all cells in the kidney (Fig. 6 E), including the tubular epithelial, vascular endothelial, mesangial, and Bowman's capsule cells; an equally well labeled probe with a similar G-C content showed no hybridization (Fig. 6 F). These observations suggest that β-netrin is a prominent element of the basement membrane and that both the epithelium and the mesenchyme contribute to its production.


A novel member of the netrin family, beta-netrin, shares homology with the beta chain of laminin: identification, expression, and functional characterization.

Koch M, Murrell JR, Hunter DD, Olson PF, Jin W, Keene DR, Brunken WJ, Burgeson RE - J. Cell Biol. (2000)

β-Netrin RNA appears not to be expressed in the floorplate of midgestation mouse embryos. (A and B) nonradioactive in situ hybridizations of floor- and roofplate markers (netrin-1, and wnt-1) show good localization of transcriptions to these structures, respectively. (C and D) Two different probes for β-netrin, on the other hand, fail to localize to any region in embryonic day 11.5 spinal cord; in D we see some above background reactivity in the lateral margins of the floorplate.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2192657&req=5

Figure 8: β-Netrin RNA appears not to be expressed in the floorplate of midgestation mouse embryos. (A and B) nonradioactive in situ hybridizations of floor- and roofplate markers (netrin-1, and wnt-1) show good localization of transcriptions to these structures, respectively. (C and D) Two different probes for β-netrin, on the other hand, fail to localize to any region in embryonic day 11.5 spinal cord; in D we see some above background reactivity in the lateral margins of the floorplate.
Mentions: Tissue distribution of the β-netrin protein was determined by indirect immunofluorescence in various rat tissues and the cellular sources of β-netrin were determined by in situ hybridization. One immediately obvious generalization is that β-netrin is expressed in the basement membranes of a variety of tissues (see Fig. 6Fig. 7Fig. 8Fig. 9). In the kidney (Fig. 6), β-netrin protein is expressed in the basement membranes of all tubules. The major arteries and arterioles (Fig. 6 A, arrows) were prominently reactive; also strongly reactive were the afferent arterioles (Fig. 6C and Fig. D). Particularly clear was the reactivity in the basal lamina surrounding the smooth muscle cells in the wall of the vessels. In addition, β-netrin immunoreactivity was present in the basement membrane of the rat glomerulus. This pattern of immunoreactivity is different than that reported for the laminin β2 chain (Hunter et al. 1989), further supporting a lack of cross-reactivity between these molecules. β-Netrin transcripts, as judged by in situ hybridization, are localized to all cells in the kidney (Fig. 6 E), including the tubular epithelial, vascular endothelial, mesangial, and Bowman's capsule cells; an equally well labeled probe with a similar G-C content showed no hybridization (Fig. 6 F). These observations suggest that β-netrin is a prominent element of the basement membrane and that both the epithelium and the mesenchyme contribute to its production.

Bottom Line: In addition, beta-netrin is expressed in a limited set of fiber tracts within the brain, including the lateral olfactory tract and the vomeronasal nerve.Functional studies were performed and show that beta-netrin promotes neurite elongation from olfactory bulb explants.Together, these data suggest that beta-netrin is important in neural, kidney, and vascular development.

View Article: PubMed Central - PubMed

Affiliation: Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.

ABSTRACT
The netrins are a family of laminin-related molecules. Here, we characterize a new member of the family, beta-netrin. beta-Netrin is homologous to the NH(2) terminus of laminin chain short arms; it contains a laminin-like domain VI and 3.5 laminin EGF repeats and a netrin C domain. Unlike other netrins, this new netrin is more related to the laminin beta chains, thus, its name beta-netrin. An initial analysis of the tissue distribution revealed that kidney, heart, ovary, retina, and the olfactory bulb were tissues of high expression. We have expressed the molecule in a eukaryotic cell expression system and made antibodies to the expressed product. Both in situ hybridization and immunohistochemistry were used to describe the cellular source of beta-netrin and where beta-netrin is deposited. beta-Netrin is a basement membrane component; it is present in the basement membranes of the vasculature, kidney, and ovaries. In addition, beta-netrin is expressed in a limited set of fiber tracts within the brain, including the lateral olfactory tract and the vomeronasal nerve. Functional studies were performed and show that beta-netrin promotes neurite elongation from olfactory bulb explants. Together, these data suggest that beta-netrin is important in neural, kidney, and vascular development.

Show MeSH
Related in: MedlinePlus