Additionally, compound heterozygous pathogenic variants of PPT1 gene were detected in a girl, who initially displayed typical RTT features, but progressed into neuronal ceroid lipofuscinoses (NCL) afterwards.
Neuronal ceroid lipofuscinosis (NCL) type 1 (CLN1) is a neurodegenerative storage disorder caused by mutations in the gene encoding the lysosomal enzyme palmitoyl-protein thioesterase 1 (PPT1).
We have conducted proteomic analyses of brain and cerebrospinal fluid (CSF) from mouse models of the most frequently diagnosed NCL diseases: CLN1 (infantile NCL), CLN2 (classical late infantile NCL) and CLN3 (juvenile NCL).
In neutral conditions, pH 6.0, the PPT1 enzyme activities in NCL 1 patients showed rather higher residual activities and intermediate activities in heterozygotes in NCL 1, which was probably caused by mutated proteins in three cases with NCL 1 patients.
Neural stem cells for disease modeling and evaluation of therapeutics for infantile (CLN1/PPT1) and late infantile (CLN2/TPP1) neuronal ceroid lipofuscinoses.
Neuronal ceroid lipofuscinoses type I and type II (NCL1 and NCL2) also known as Batten disease are the commonly observed neurodegenerative lysosomal storage disorder caused by mutations in the PPT1 and TPP1 genes respectively.
CLN1 disease (OMIM #256730) is an early childhood ceroid-lipofuscinosis associated with mutated <i>CLN1</i>, whose product Palmitoyl-Protein Thioesterase 1 (PPT1) is a lysosomal enzyme involved in the removal of palmitate residues from S-acylated proteins.
To identify candidate biomarkers, we analyzed autopsy brain and matching CSF samples from controls and three genetically distinct NCLs due to deficiencies in palmitoyl protein thioesterase 1 (CLN1 disease), tripeptidyl peptidase 1 (CLN2 disease), and CLN3 protein (CLN3 disease).
Infantile-onset NCL (CLN1 disease) is caused by severe deficiency in a soluble lysosomal enzyme, palmitoyl-protein thioesterase-1 (PPT1) and no therapy beyond supportive care is available.
Mutations in the depalmitoylating enzyme gene, PPT1, cause the infantile form of Neuronal Ceroid Lipofuscinosis (NCL), an early onset neurodegenerative disease.
Nonsense mutations in CLN1 account for 52.3% of all disease causing alleles in infantile NCL, the most common of which worldwide is the p.R151X mutation.
Nonsense mutations in CLN1 account for 52.3% of all disease causing alleles in infantile NCL, the most common of which worldwide is the p.R151X mutation.
The NCLs are clinically and genetically heterogeneous and more than 14 genetically distinct NCL subtypes have been described to date (CLN1-CLN14) (Haltia and Goebel, 2012 [1]).
In total six PATs (HIP14, HIP14L, ZDHHC8, ZDHHC9, ZDHHC12, and ZDHHC15) and one thioesterase (PPT1) have been implicated in Huntington disease (HD), Alzheimer disease, schizophrenia, mental retardation, and infantile and adult onset forms of neuronal ceroid lipofuscinosis.
Although functions are defined for some of the soluble proteins that are defective in NCL (cathepsin D, PPT1, and TPP1), the primary function of the other proteins defective in NCLs (CLN3, CLN5, CLN6, CLN7, and CLN8) remain poorly defined.
To date, 10 NCL entities (CLN1-CLN10) are known and characterized by accumulation of autofluorescent storage material, age of onset and clinical symptoms.
Cases of ceroid lipofuscinosis with cytoplasmic storage of granular osmiophilic deposits are associated with reduced activity of palmitoyl-protein thioesterase-1 (PPT-1) and mutations in CLN1, and occur from infancy to adulthood.
The late-infantile-onset forms of neuronal ceroid lipofuscinosis (LINCL) are the most genetically heterogeneous group among the autosomal recessive neuronal ceroid lipofuscinoses (NCLs), with causative mutations found in CLN1, CLN2, CLN5, CLN6, CLN7 (MFSD8), and CLN8 genes.