Antibody against nerve growth factor-inducible large external (NILE) glycoprotein labels nerve fiber tracts in the developing rat nervous system

Abstract

The NILE (nerve growth factor-inducible large external) glycoprotein is a 230,000-dalton molecule found on the surface of PC12 cells. immunologically cross-reactive glycoproteins in the molecular weight range of 215,000 to 230,000 have been found on many types of neurons in culture. Using immunohistochemical methods, we have shown that NILErelated glycoproteins are present in neuronal fiber tracts of the developing rat brain. Antibody against the NILE glycoprotein specifically labels processes that appear identical to those recognized by antibodies against the neurofilament triplet of proteins. These processes are clearly distinct from the radial glial fibers recognized by antibody against the intermediate filament protein vimentin. NILE glycoprotein is not distributed uniformly over the entire neuronal surface but is concentrated on neurites and is much less abundant on cell bodies. NILE-positive fiber tracts are first seen in the spinal cord and rhombencephalon on embryonic day 11 and over the next 2 days appear in the mesencephalon and diencephalon.Staining in the telencephalon is not seen until embryonic day 15. The appearance of NILE immunoreactivity in these various regions closely parallels the appearance of neurofilament polypeptides, suggesting that NILE-related glycoproteins are present during the early phases of fiber tract formation. This idea is supported by the finding that the NILE glycoprotein can be found postnatally in parts of the nervous system such as the cerebellar cortex and olfactory bulb which undergo major histogenesis during the postnatal period. In the cerebellum the appearance of NILE immunoreactivity in the two major fiber zones, the molecular layer and the white matter, parallels the development of the fiber structure of these layers. These findings support tissue culture studies which suggest a role for the NILE glycoprotein in mediating nerve fiber fasciculation.

The neural restrictive silencer element can act as both a repressor and enhancer of L1 cell adhesion molecule gene expression during postnatal development

“…In a previous study (16), we found that a construct called L1lacZ containing an 18-kb segment of the mouse L1 gene produced a neurally restricted pattern of ␤-galactosidase expression. This pattern was in accord with previous immunohistochemical and in situ hybridization studies that localized the protein and mRNA expression for L1 during early neural development (12,20,25,26). L1lacZ⌬N, a construct similar to L1lacZ but lacking the NRSE normally found in the second intron of the L1 gene, showed ectopic L1 promoter activity in several nonneural tissues between days 8.5 and 13.5 of embryonic development (16).…”

“…Although the L1 cell adhesion molecule is first expressed during the differentiation of postmitotic neurons from neuroepithelial precursors (20), the most abundant expression of L1 mRNA and protein occurs during the period of postnatal development (21). At this time, there is an extensive outgrowth of neurons and formation of synaptic connections.…”

Regulation of axonal growth in the vertebrate nervous system by interactions between glycoproteins belonging to two subgroups of the immunoglobulin superfamily.

“…Furthermore, several independent in vitro experiments, including antibody perturbation studies and direct neurite outgrowth assays using these proteins, either immobilized on cell culture dishes or expressed by transfection in cell lines, have revealed compelling evidence that these Ig/FNIII-like proteins participate in axonal growth processes (Stallcup and Beasley, 1985;Hoffman et al, 1986;Fischer et al, 1986;Chang et al, 1987;Rathjen et al, 1987a,b;Lagenaur and Lemmon, 1987;Ruegg et al, 1989;Chang et al, 1990;Furley et al, 1990;Kadmon et al, 1990;Stoeckli et al, 1991;Gennarini et al, 1991).…”

L1 cell adhesion molecule is not required for small-diameter primary afferent sprouting after deafferentation

“…L1 plays a role in axonal outgrowth, fasciculation, and guidance during spinal cord development (Stallcup et al, 1985;Jessell, 1988;Stoeckli and Landmesser, 1995;Orlino et al, 2000;Tran and Phelps, 2000;Akopians et al, 2003) through homophilic and various heterophilic binding partners such as integrins (αVβ3 and α5β1) and the fibroblast growth factor receptor (Kamiguchi and Lemmon, 1997). L1 interacts with TAG-1 and DM-1 GRASP to promote neurite growth, whereas binding with *Please address correspondence to: Patricia E. Phelps, Ph.D., Dept.…”