This report describes Parkinson disease 5 (PARK5, PD5), which is a subtype of Parkinson disease; PARK5 exhibits autosomal dominant inheritance. The human gene implicated in this disease is UCHL1, Ubiquitin carboxyl-terminal esterase L1, which is involved in the processing of ubiquitin precursors and of ubiquitinated proteins. UCHL1 is also implicated in a form of spastic paraplegia (SPG7; MIM:615491). There is a single orthologous gene in Drosophila, Uch, for which RNAi-targeting constructs and alleles caused by insertional mutagenesis have been generated. Dmel\Uch is also orthologous to the human gene UCHL3.
A UAS construct of a tagged human Hsap\UCHL1 gene has been introduced into flies, but has not been characterized in the context of this disease model.
RNAi-mediated knockdown of Dmel\Uch in dopaminergic neurons (DA neurons) results in the underdevelopment and/or progressive degeneration of the DA neurons; adult animals exhibit age-dependent locomotor defects. Many physical interactions have been described for Dmel\Uch; see below and in the Uch gene report.
[updated Nov. 2018 by FlyBase; FBrf0222196]
Parkinson disease (PD) is a neurodegenerative disease usually typified by slow onset in mid to late adulthood; there are also early-onset and juvenile forms of the disease. Symptoms worsen over time and include resting tremor, muscular rigidity, bradykinesia [abnormal slowness of movement], and postural instability [impaired balance and coordination]; additional symptoms may include postural abnormalities, dysautonomia [symptoms caused by malfunction of the autonomic nervous system], dystonic cramps, and dementia. Parkinson disease is the second-most common neurodegenerative disease (after Alzheimer disease), affecting approximately 1% of the population over 50 (Polymeropoulos et al., 1996, pubmed:8895469). [from MIM:168600; 2013.07.23]
Parkinson disease is described as early-onset disease if signs and symptoms begin before age 50. Early-onset cases that begin before age 20 may be referred to as juvenile-onset disease. [from Genetics Home Reference, GHR_condition:parkinson-disease, 2015.02.13]
[PARKINSON DISEASE 5, AUTOSOMAL DOMINANT, SUSCEPTIBILITY TO; PARK5](https://omim.org/entry/613643)
[UBIQUITIN CARBOXYL-TERMINAL ESTERASE L1; UCHL1](https://omim.org/entry/191342)
Susceptibility to autosomal dominant Parkinson disease-5 (PARK5) is conferred by heterozygous mutation in the UCHL1 gene; one such family has been reported. [from MIM:613643; 2018.07.24]
UCHL1 encodes a ubiquitin-protein hydrolase involved both in the processing of ubiquitin precursors and of ubiquitinated proteins. [Gene Cards, UCHL1; 2018.07.24]
Ubiquitin carboxyl-terminal esterase L1 (UCHL1) is a member of a gene family whose products hydrolyze small C-terminal adducts of ubiquitin to generate the ubiquitin monomer. Expression of UCHL1 is highly specific to neurons and to cells of the diffuse neuroendocrine system. It is present in all neurons (Doran et al., 1983; pubmed:6343558). [from MIM:191342; 2018.07.24]
Many to one (2 human to 1 Drosophila); the other human gene is UCHL3.
Moderate- to high-scoring ortholog of human UCHL3 and UCHL1 (1 Drosophila to 2 human). Dmel\Uch shares 40-46% identity and 54-67% similarity with the human genes.