Description:

Amyotrophic lateral sclerosis is a devastating disease, and thus it is important to identify the causative gene and resolve the mechanism of the disease. We identified optineurin as a causative gene for amyotrophic lateral sclerosis. We found three types of mutations: a homozygous deletion of exon 5, a homozygous Q398X nonsense mutation and a heterozygous E478G missense mutation within its ubiquitin-binding domain. Optineurin negatively regulates the tumor necrosis factor-α-induced activation of nuclear factor kappa B. Nonsense and missense mutations abolished this function. Mutations related to amyotrophic lateral sclerosis also negated the inhibition of interferon regulatory factor-3. The missense mutation showed a cyotoplasmic distribution different from that of the wild type. There are no specific clinical symptoms related to optineurin. However, severe brain atrophy was detected in patients with homozygous deletion. Neuropathologically, an E478G patient showed transactive response DNA-binding protein of 43 kDa-positive neuronal intracytoplasmic inclusions in the spinal and medullary motor neurons. Furthermore, Golgi fragmentation was identified in 73% of this patient's anterior horn cells. In addition, optineurin is colocalized with fused in sarcoma in the basophilic inclusions of amyotrophic lateral sclerosis with fused in sarcoma mutations, and in basophilic inclusion body disease. These findings strongly suggest that optineurin is involved in the pathogenesis of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis is a progressive neurodegenerative syndrome characterized by loss of motor neurons. Cognitive impairment occurs in a significant proportion of those affected. Numerous theories of pathogenesis have been advanced. The most cogent hypothesis is that genetic susceptibilities to neurodegeneration interact with environmental exposures, leading to neuronal injury, glial activation and neuronal death. Modern tools of molecular and cell biology and constructive international collaborations have provided insights into the factors that increase disease susceptibility. The important observation that genes associated with ribonucleic acid (RNA) processing are implicated in disease pathogenesis will undoubtedly influence the direction of research in the coming years. These factors, combined with improvements in clinical trial design, and an improved understanding of the limitations of translating positive findings from animal models to human subjects, are likely to lead to new and successful therapeutic options for patients in the near future.

With Regards
Meery
Journal Coordinator
Global Journal of Research and Review