Remyelination plays an important role in determining the fate of demyelinating disorders. However, it is arrested during chronic disease states. Cystatin F, a papain-like lysosomal cysteine proteinase inhibitor, is a crucial regulator of demyelination and remyelination. Using hemizygous proteolipid protein transgenic 4e (PLP4e/-) mice, an animal model of chronic demyelination, we found that cystatin F mRNA expression was induced at 2.5 months of age and up-regulated in the early phase of demyelination, but significantly decreased in the chronic phase. We next investigated cystatin F regulatory factors as potential mechanisms of remyelination arrest in chronic demyelinating disorders. We used the CysF-STOP-tetO::Iba-mtTA mouse model, in which cystatin F gene expression is driven by the tetracycline operator. Interestingly, we found that forced cystatin F mRNA over-expression was eventually decreased. Our findings show that cystatin F expression is modulated post-transcriptionally. We next identified embryonic lethal, abnormal vision, drosophila like RNA-binding protein 1 (ELAVL-1), and miR29a as cystatin F mRNA stabilizing and destabilizing factors, respectively. These roles were confirmed in vitro in NIH3T3 cells. Using postmortem plaque samples from human multiple sclerosis patients, we also confirmed that ELAVL-1 expression was highly correlated with the previously reported expression pattern of cystatin F. These data indicate the important roles of ELAVL-1 and miR29a in regulating cystatin F expression. Furthermore, they provide new insights into potential therapeutic targets for demyelinating disorders. (Figure presented.).
Bibliographical noteFunding Information:
This work was funded by a Grant‐in‐Aid for Scientific Research on Innovative Areas: “Foundation of Synapse and Neurocircuit Pathology (23110521),” Japan Society for the Promotion of Science (JSPS), “Glial Assembly: a new regulatory machinery of brain function and disorders (25117001)” and by the Thailand Research Fund under the Royal Golden Jubilee‐Ph.D. Scholarship and Mahidol University to WW and BC. The CysF‐STOP‐tetO, Iba‐mtTA, MLC‐mtTA, and mice were provided by Takahiro Shimizu in the Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Japan, and Kenji Tanaka in the Department of Neuropsychiatry, Keio University, Tokyo, Japan. The human tissue was provided by the Collaborative Research Project of the Brain Research Institute, Niigata University. We are grateful for the technical assistance provided by Hirokazu Hashimoto from the Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Japan. PLP 4e/‐
- cystatin F
- demyelinating diseases
- gene expression regulation
PubMed: MeSH publication types
- Journal Article