Encyclopedia
DnaJ Heat Shock Protein Family (Hsp40) Member C5
- genes
1. Normal Function
The DNAJC5 gene provides instructions for making a protein called cysteine string protein alpha (CSPα). This protein is found near nerve cells in the brain, where it plays a role in the transmission of nerve impulses. Specifically, CSPα is part of a group (complex) of proteins that is found on the membrane of sac-like structures called synaptic vesicles. Synaptic vesicles are found close to the ends of nerve cells and contain chemical messengers that transmit signals from one nerve cell to another. CSPα is involved in recycling proteins that are involved in nerve impulse transmission by re-folding misshapen proteins so that they can be used in additional transmissions.
2. Health Conditions Related to Genetic Changes
2.1 CLN4 Disease
At least two mutations in the DNAJC5 gene have been found to cause CLN4 disease. CLN4 disease is an inherited disorder that primarily affects the nervous system. This condition usually begins in adulthood with problems with movement and intellectual function that worsen over time.
One of the DNAJC5 gene mutations replaces the protein building block (amino acid) leucine with the amino acid arginine at position 115 in the CSPα protein (written as L115R). The other mutation deletes the amino acid leucine at position 116 in the protein (written as L116del). Affected individuals have one of these mutations in one copy of the DNAJC5 gene in each cell, which leads to the production of an altered protein that cannot associate with the membrane of synaptic vesicles. The resulting reduction in protein recycling leads to a shortage (deficiency) of functional proteins, which impairs the efficiency of nerve impulse transmission. The abnormal CSPα protein may also bind to the functional CSPα protein that is produced from the normal copy of the DNAJC5 gene and prevent it from associating with synaptic vesicles, further impairing impulse transmission. Without communication between nerve cells, neurological functions are impaired, contributing to the features of CLN4 disease.
CLN4 disease is characterized by the accumulation of proteins and other substances in lysosomes, which are compartments in the cell that digest and recycle materials. These accumulations occur in cells throughout the body; however, nerve cells seem to be particularly vulnerable to their effects. The accumulations can cause cell damage leading to cell death. The progressive death of nerve cells in the brain and other tissues contributes to the decline of neurological function in CLN4 disease. However, it is unclear how mutations in the DNAJC5 gene are involved in the buildup of substances in lysosomes.
3. Other Names for This Gene
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CLN4
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CLN4B
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CSP
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cysteine string protein alpha
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DnaJ (Hsp40) homolog, subfamily C, member 5
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dnaJ homolog subfamily C member 5
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DNAJC5A
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DNJC5_HUMAN
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FLJ00118
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FLJ13070
This entry is adapted from the peer-reviewed paper https://medlineplus.gov/genetics/gene/dnajc5
References
- Benitez BA, Alvarado D, Cai Y, Mayo K, Chakraverty S, Norton J, Morris JC,Sands MS, Goate A, Cruchaga C. Exome-sequencing confirms DNAJC5 mutations ascause of adult neuronal ceroid-lipofuscinosis. PLoS One. 2011;6(11):e26741. doi: 10.1371/journal.pone.0026741.
- Cadieux-Dion M, Andermann E, Lachance-Touchette P, Ansorge O, Meloche C,Barnabé A, Kuzniecky RI, Andermann F, Faught E, Leonberg S, Damiano JA, Berkovic SF, Rouleau GA, Cossette P. Recurrent mutations in DNAJC5 cause autosomaldominant Kufs disease. Clin Genet. 2013 Jun;83(6):571-5. doi: 10.1111/cge.12020.
- Cárcel-Trullols J, Kovács AD, Pearce DA. Cell biology of the NCL proteins:What they do and don't do. Biochim Biophys Acta. 2015 Oct;1852(10 Pt B):2242-55. doi: 10.1016/j.bbadis.2015.04.027.
- Henderson MX, Wirak GS, Zhang YQ, Dai F, Ginsberg SD, Dolzhanskaya N,Staropoli JF, Nijssen PC, Lam TT, Roth AF, Davis NG, Dawson G, Velinov M, ChandraSS. Neuronal ceroid lipofuscinosis with DNAJC5/CSPα mutation has PPT1 pathologyand exhibit aberrant protein palmitoylation. Acta Neuropathol. 2016Apr;131(4):621-37. doi: 10.1007/s00401-015-1512-2.
- Tobaben S, Thakur P, Fernández-Chacón R, Südhof TC, Rettig J, Stahl B. Atrimeric protein complex functions as a synaptic chaperone machine. Neuron. 2001 Sep 27;31(6):987-99.
- Velinov M, Dolzhanskaya N, Gonzalez M, Powell E, Konidari I, Hulme W,Staropoli JF, Xin W, Wen GY, Barone R, Coppel SH, Sims K, Brown WT, Züchner S.Mutations in the gene DNAJC5 cause autosomal dominant Kufs disease in aproportion of cases: study of the Parry family and 8 other families. PLoS One.2012;7(1):e29729. doi: 10.1371/journal.pone.0029729.PLoS One. 2012;7(9). doi:10.1371/annotation/26d7eb64-ccd2-41db-b1aa-7cdc8c1eff95.
