Greaves, Jennifer and Lemonidis, Kimon and Gorleku, Oforiwa and Cruchaga, Carlos and Grefen, Christopher and Chamberlain, Luke (2012) Palmitoylation-induced aggregation of cysteine-string protein mutants that cause neuronal ceroid lipofuscinosis. Journal of Biological Chemistry, 287 (44). pp. 37330-37339. ISSN 1083-351XFull text not available in this repository. (Request a copy from the Strathclyde author)
Recently, mutations in the DNAJC5 gene encoding cysteine-string protein alpha (CSPα) were identified to cause the neurodegenerative disorder adult-onset neuronal ceroid lipofuscinosis. The disease-causing mutations (L115R or ΔL116) occur within the cysteine-string domain, a region of the protein that is post-translationally modified by extensive palmitoylation. Here we demonstrate that L115R and ΔL116 mutant proteins are mis-targeted in neuroendocrine cells and form SDS-resistant aggregates, concordant with the properties of other mutant proteins linked to neurodegenerative disorders. The mutant aggregates are membrane-associated and incorporate palmitate. Indeed, co-expression of palmitoyl transferase enzymes promoted the aggregation of the CSPα mutants, and chemical depalmitoylation solubilized the aggregates, demonstrating that aggregation is induced and maintained by palmitoylation. In agreement with these observations, SDS-resistant CSPα aggregates were present in brain samples from patients carrying the L115R mutation, and were depleted by chemical depalmitoylation. In summary, this study identifies a novel interplay between genetic mutations and palmitoylation in driving aggregation of CSPα mutant proteins. We propose that this palmitoylation-induced aggregation of mutant CSPα proteins may underlie the development of adult-onset neuronal ceroid lipofuscinosis in affected families.
|Keywords:||exocytosis , protein palmitoylation, protein aggregation , protein acylation , membrane trafficking , palmitoylation-induced aggregation , cysteine-string protein mutants , neuronal ceroid lipofuscinosis, Pharmacy and materia medica, Biochemistry, Cell Biology, Molecular Biology|
|Subjects:||Medicine > Pharmacy and materia medica|
|Department:||Faculty of Science > Strathclyde Institute of Pharmacy and Biomedical Sciences|
|Depositing user:||Pure Administrator|
|Date Deposited:||03 Oct 2012 13:27|
|Last modified:||31 Mar 2017 03:37|