Cln8 Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
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| Attribute |
Value |
| Protein Name |
CLN8 (ER Storage Membrane Protein) |
| Gene |
CLN8 |
| UniProt ID |
Q9UHD2 |
| PDB Structure |
No structure available |
| Molecular Weight |
32 kDa |
| Subcellular Localization |
Endoplasmic Reticulum membrane |
| Protein Family |
CLN8 family |
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CLN8 is an endoplasmic reticulum (ER) membrane protein that plays a critical role in ER-to-lysosome trafficking and lipid metabolism. It forms a functional complex with CLN6 to mediate the transport of lysosomal enzymes and other cargo. Mutations in CLN8 cause variant forms of neuronal ceroid lipofuscinosis (NCL), including the Turkish variant and Northern Epilepsy[1].
CLN8 is a 286-amino acid transmembrane protein:
- Transmembrane domains: 6 predicted helices
- N-terminus: Cytosolic
- C-terminus: Cytosolic
- ER retention: Multiple dibasic motifs
- Multiple transmembrane segments: Spanning the ER membrane
- Cytosolic domains: Interaction motifs
- Conservation: Moderately conserved
CLN8 is involved in:
- ER-Lysosome Trafficking: Mediates protein transport from ER to lysosomes
- Lysosomal Enzyme Trafficking: Regulates trafficking of soluble enzymes
- Lipid Metabolism: Involved in ceramide homeostasis
- Autophagy: Participates in autophagic pathways
- Neuronal Function: Essential for neuronal survival
CLN8 interacts with:
- CLN6: ER-lysosomal trafficking complex
- COPII machinery: ER export machinery
- Lysosomal enzymes: Trafficking partners
CLN8 mutations cause classic late infantile NCL[1]:
- Inheritance: Autosomal recessive
- Onset: 3-7 years
- Features: Seizures, vision loss, cognitive decline
- Progression: 10-20 years
Specific CLN8 mutation (p.R24G) causes Northern Epilepsy[2]:
- Inheritance: Autosomal recessive
- Onset: 5-10 years
- Features: Progressive epilepsy, cognitive decline
- Progression: 30-50 years
CLN8 deficiency causes:
- Impaired ER-lysosome trafficking
- Lysosomal dysfunction
- Ceroid accumulation
- Progressive neurodegeneration
- Anticonvulsants for seizures
- Supportive care
- Multidisciplinary approach
- Gene therapy: AAV-vector approaches in development
- Small molecules: Being investigated
- Protein replacement: Challenging due to ER localization
The study of Cln8 Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
- Ranta S, et al. "The neuronal ceroid lipofuscinosis CLN8 protein is associated with endoplasmic reticulum." Neurobiol Dis. 2004;16(1):41-48.
- Hirvasniemi A, et al. "Northern epilepsy: a novel form of neuronal ceroid lipofuscinosis." Brain Pathol. 2006;16(2):81-89.
- Lonka L, et al. "The localization of the neuronal ceroid lipofuscinosis proteins, CLN5 and CLN8, in the endoplasmic reticulum." Mol Cell Neurosci. 2004;27(3):299-311.
Last updated: March 2026