Figures
Laminin 211 inhibits protein kinase A in Schwann cells to modulate neuregulin 1 type III-driven myelination
Myelin is formed by the wrapping of glial cell membranes around axons and is required for the fast conduction of nerve impulses and to support axons. In the peripheral nervous system, myelin is produced by Schwann cells, and defects in peripheral myelin can cause debilitating diseases whose molecular mechanisms are only partially understood. This study by Ghidinelli et al. reveals how two crucial extracellular modulators of myelin formation—neuregulin 1 type III (Nrg1III) and laminin α2β1γ1 (Lm211)—work together in the peripheral nervous system. Although Lm211 was believed to promote myelination, the authors show here that it can also inhibit myelin formation by suppressing the activity of Nrg1III, limiting the activation of its downstream signaling cascade. These results help to explain why certain inherited neuropathies are characterized by hypermyelination and redundant myelin sheaths. The image shows myelin formed in vitro by Schwann cells when co-cultured with dorsal root ganglion neurons for this study.
Image Credit: Angelo Quattrini and Paola Podini, San Raffaele Scientific Institute
Citation: (2017) PLoS Biology Issue Image | Vol. 15(6) June 2017. PLoS Biol 15(6): ev15.i06. https://doi.org/10.1371/image.pbio.v15.i06
Published: June 30, 2017
Copyright: © 2017 Quattrini and Podini, San Raffaele Scientific Insititute. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Myelin is formed by the wrapping of glial cell membranes around axons and is required for the fast conduction of nerve impulses and to support axons. In the peripheral nervous system, myelin is produced by Schwann cells, and defects in peripheral myelin can cause debilitating diseases whose molecular mechanisms are only partially understood. This study by Ghidinelli et al. reveals how two crucial extracellular modulators of myelin formation—neuregulin 1 type III (Nrg1III) and laminin α2β1γ1 (Lm211)—work together in the peripheral nervous system. Although Lm211 was believed to promote myelination, the authors show here that it can also inhibit myelin formation by suppressing the activity of Nrg1III, limiting the activation of its downstream signaling cascade. These results help to explain why certain inherited neuropathies are characterized by hypermyelination and redundant myelin sheaths. The image shows myelin formed in vitro by Schwann cells when co-cultured with dorsal root ganglion neurons for this study.
Image Credit: Angelo Quattrini and Paola Podini, San Raffaele Scientific Institute