We have studied the transcription factors SCIP and Krox-20 in differentiating Schwann cells-during normal development, in experimentally induced degenerating and regenerating peripheral nerves, and in cell culture-and have compared the expression of these regulators to a battery of genes that mark distinct stages in Schwann cell differentiation. In the myelinating Schwann cell lineage, we find ...

To investigate the function of laminin in peripheral nerve development, we specifically disrupted the laminin gamma1 gene in Schwann cells. Disruption of laminin gamma1 gene expression resulted in depletion of all other laminin chains known to be expressed in Schwann cells. Schwann cells lacking laminin do not extend processes required for initiating axonal sorting and mediating axon-Schwann ce...

Axons of dorsal root ganglion neurons express on their surfaces one or more proteins which are mitogenic for Schwann cells (Salzer, J., R. P. Bunge, and L. Glaser, 1980, J. Cell Biol., 84:767-778). Incubation of co-cultures of dorsal root ganglion neurons and Schwann cells with 4-methylumbelliferyl-beta-D-xyloside, an inhibitor of proteoglycan biosynthesis, decreases the mitogenic response of t...

Schwann cell proliferation induced by a myelin-enriched fraction was examined in vitro. Although nearly all the Schwann cells contained material that was recognized by antisera to myelin basic protein after 24 h, only 1% of the cells were synthesizing DNA. 72 h after the addition of the mitogen a maximum of 10% of the cells incorporated [3H]thymidine. If the cultures were treated with the myeli...

We have generated previously transgenic rats that overexpress peripheral myelin protein 22 (PMP22) in Schwann cells. In the nerves of these animals, Schwann cells have segregated with axons to the normal 1:1 ratio but remain arrested at the promyelinating stage, apparently unable to elaborate myelin sheaths. We have examined gene expression of these dysmyelinating Schwann cells using semiquanti...

Schwann cells, from a variety of sources, are known to possess P2Y purinergic metabotropic receptors. However, it is not known if Schwann cells associated with autonomic nerve terminals possess such receptors and if so whether these receptors are activated by the endogenous release of ATP from the nerve terminals. We show that such Schwann cells in the vas deferens give evoked calcium transient...

Myelin basic proteins (MBP) are major constituents of the myelin sheath in the central nervous system (CNS) and the peripheral nervous system (PNS). In the CNS Mbp translation occurs locally at the axon-glial contact site in a neuronal activity-dependent manner. Recently we identified the small non-coding RNA 715 (sncRNA715) as a key inhibitor of Mbp translation during transport in oligodendroc...

In the vertebrate embryo, the neural crest cells (NCCs) that migrate out from the neural primordium yield multiple phenotypes, including melanocytes, peripheral neurones and glia and, in the head, cartilage, bone, connective cells and myofibroblasts / vascular smooth muscle cells (SMCs). The differentiation of pluripotent NCCs is mainly directed by local growth factors. Even at postmigratory st...

Schwann cells promote the regrowth of nerve fibers in both the PNS and CNS and might thus be of value in strategies to promote repair following injury or demyelination in the CNS. The effectiveness of Schwann cells in promoting repair could, however, be limited by interactions with reactive astrocytes that are prominent at lesioned and demyelinated sites. To investigate this possibility, experi...

Schwann cells develop from the neural crest in a well-defined sequence of events. This involves the formation of the Schwann cell precursor and immature Schwann cells, followed by the generation of the myelin and nonmyelin (Remak) cells of mature nerves. This review describes the signals that control the embryonic phase of this process and the organogenesis of peripheral nerves. We also discuss...