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arXiv · 0704.3263

Effect of beta-Dystroglycan Processing on Utrophin / DP116 Anchorage in Normal and MDX Mouse Schwann Cell Membrane

Karim Hnia·Gérald Hugon·Ahmed Masmoudi·Jacques Mercier·François Rivier·Dominique Jean-Marie Mornet
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Abstract

In the peripheral nervous system, utrophin and the short dystrophin isoform (Dp116) are co-localized at the outermost layer of the myelin sheath of nerve fibers; together with the dystroglycan complex. In peripheral nerve, matrix metalloproteinase (MMP) creates a 30 kDa fragment of beta-dystroglycan, leading to a disruption of the link between the extracellular matrix and the cell membrane. Here we asked if the processing of the beta-dystroglycan could influence the anchorage of Dp116 or/and utrophin in normal and mdx Schwann cell membrane. We showed that MMP-9 was more activated in mdx nerve than in wild-type one. This activation leads to an accumulation of the 30 kDa beta-dystroglycan isoform and have an impact on the anchorage of Dp116 and utrophin isoforms in mdx Schwann cells membrane. Our results showed that Dp116 had greater affinity to the full length form of beta-dystroglycan than the 30 kDa form. Moreover, we showed for the first time that the short isoform of utrophin (Up71) was over-expressed in mdx Schwann cells compared to wild-type. In addition, this utrophin isoform (Up71) seems to have greater affinity to the 30 kDa beta-dystroglycan which could explain a more stabilization of this 30 kDa at the membrane compartment. Our results highlight the potential participation of the short utrophin isoform and the cleaved form of beta-dystroglycan in mdx Schwann cell membrane architecture.

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Karim Hnia, Gérald Hugon, Ahmed Masmoudi, Jacques Mercier, François Rivier, Dominique Jean-Marie Mornet. 2007-04-24. Effect of beta-Dystroglycan Processing on Utrophin / DP116 Anchorage in Normal and MDX Mouse Schwann Cell Membrane. https://doi.org/10.1016/j.neuroscience.2006.04.043

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