Amyotrophic Lateral Sclerosis Modifiers in Drosophila Reveal the Phospholipase D Pathway as a Potential Therapeutic Target

Amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig’s disease, is a devastating neurodegenerative disorder lacking effective treatments. ALS pathology is linked to mutations in >20 different genes indicating a complex underlying genetic architecture that is effectively unknown. Here, in an attempt to identify genes and pathways for potential therapeutic intervention and explore the genetic circuitry underlying Drosophila models of ALS, we carry out two independent genome-wide screens for modifiers of degenerative phenotypes associated with the expression of transgenic constructs carrying familial ALS-causing alleles of FUS (hFUSR521C) and TDP-43 (hTDP-43M337V). We uncover a complex array of genes affecting either or both of the two strains, and investigate their activities in additional ALS models. Our studies indicate the pathway that governs phospholipase D activity as a major modifier of ALS-related phenotypes, a notion supported by data we generated in mice and others collected in humans.

Download Full-text

IBD analysis of Australian amyotrophic lateral sclerosis SOD1-mutation carriers identifies five founder events and links sporadic cases to existing ALS families

10.1101/685925 ◽

2019 ◽

Cited By ~ 2

Author(s):

Lyndal Henden ◽

Natalie A. Twine ◽

Piotr Szul ◽

Emily P. McCann ◽

Garth A. Nicholson ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Motor Neurons ◽

Neurodegenerative Disorder ◽

Sporadic Case ◽

Sporadic Als ◽

Disease Penetrance ◽

Sporadic Cases ◽

Familial Als ◽

Founder Events ◽

Lateral Sclerosis

AbstractAmyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterised by the loss of upper and lower motor neurons resulting in paralysis and eventual death. Approximately 10% of ALS cases have a family history of disease, while the remaining cases present as apparently sporadic. Heritability studies suggest a significant genetic component to sporadic ALS, and although most sporadic cases have an unknown genetic etiology, some familial ALS mutations have also been found in sporadic cases. This suggests that some sporadic cases may be unrecognised familial cases with reduced disease penetrance. Identifying a familial basis of disease in apparently sporadic ALS cases has significant genetic counselling implications for immediate relatives. A powerful strategy to uncover a familial link is identity-by-descent (IBD) analysis which detects genomic regions that have been inherited from a common ancestor. We performed IBD analysis on 90 Australian familial ALS cases from 25 families and three sporadic ALS cases, each of whom carried one of three SOD1 mutations (p.I114T, p.V149G and p.E101G). We identified five unique haplotypes that carry these mutations in our cohort, indicative of five founder events. This included two different haplotypes that carry SOD1 p.I114T, where one haplotype was present in one sporadic case and 20 families, while the second haplotype was found in the remaining two sporadic cases and one family, thus linking these familial and sporadic cases. Furthermore, we linked two families that carry SOD1 p.V149G and found that SOD1 p.E101G arose independently in each family that carries this mutation.

Download Full-text

Using Drosophila melanogaster To Discover Human Disease Genes: An Educational Primer for Use with “Amyotrophic Lateral Sclerosis Modifiers in Drosophila Reveal the Phospholipase D Pathway as a Potential Therapeutic Target”

Genetics ◽

10.1534/genetics.120.303495 ◽

2020 ◽

Vol 216 (3) ◽

pp. 633-641

Author(s):

Surya Banerjee ◽

Shimshon Benji ◽

Sarah Liberow ◽

Josefa Steinhauer

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Drosophila Melanogaster ◽

Phospholipase D ◽

Therapeutic Target ◽

Human Disease ◽

Disease Genes ◽

Genetic Screens ◽

Potential Therapeutic Target ◽

Human Disease Genes ◽

Lateral Sclerosis

Since the dawn of the 20th century, the fruit fly Drosophila melanogaster has been used as a model organism to understand the nature of genes and how they control development, behavior, and physiology. One of the most powerful experimental approaches employed in Drosophila is the forward genetic screen. In the 21st century, genome-wide screens have become popular tools for identifying evolutionarily conserved genes involved in complex human diseases. In the accompanying article “Amyotrophic Lateral Sclerosis Modifiers in Drosophila Reveal the Phospholipase D Pathway as a Potential Therapeutic Target,” Kankel and colleagues describe a forward genetic modifier screen to discover factors that contribute to the severe neurodegenerative disease amyotrophic lateral sclerosis (ALS). This primer briefly traces the history of genetic screens in Drosophila and introduces students to ALS. We then provide a set of guided reading questions to help students work through the data presented in the research article. Finally, several ideas for literature-based research projects are offered as opportunities for students to expand their appreciation of the potential scope of genetic screens. The primer is intended to help students and instructors thoroughly examine a current study that uses forward genetics in Drosophila to identify human disease genes.

Download Full-text

Genome-wide association analyses identify new risk variants and the genetic architecture of amyotrophic lateral sclerosis

Nature Genetics ◽

10.1038/ng.3622 ◽

2016 ◽

Vol 48 (9) ◽

pp. 1043-1048 ◽

Cited By ~ 254

Author(s):

Wouter van Rheenen ◽

◽

Aleksey Shatunov ◽

Annelot M Dekker ◽

Russell L McLaughlin ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Genetic Architecture ◽

Genome Wide Association ◽

Association Analyses ◽

Risk Variants ◽

Genome Wide ◽

Lateral Sclerosis

Download Full-text

Genetic analysis of amyotrophic lateral sclerosis identifies contributing pathways and cell types

Science Advances ◽

10.1126/sciadv.abd9036 ◽

2021 ◽

Vol 7 (3) ◽

pp. eabd9036

Author(s):

Sara Saez-Atienzar ◽

Sara Bandres-Ciga ◽

Rebekah G. Langston ◽

Jonggeol J. Kim ◽

Shing Wan Choi ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Membrane Trafficking ◽

Molecular Mechanisms ◽

Cell Types ◽

Polygenic Risk Score ◽

Genome Wide ◽

Genome Wide Data ◽

Data Driven Approach ◽

Single Nucleus ◽

Lateral Sclerosis

Despite the considerable progress in unraveling the genetic causes of amyotrophic lateral sclerosis (ALS), we do not fully understand the molecular mechanisms underlying the disease. We analyzed genome-wide data involving 78,500 individuals using a polygenic risk score approach to identify the biological pathways and cell types involved in ALS. This data-driven approach identified multiple aspects of the biology underlying the disease that resolved into broader themes, namely, neuron projection morphogenesis, membrane trafficking, and signal transduction mediated by ribonucleotides. We also found that genomic risk in ALS maps consistently to GABAergic interneurons and oligodendrocytes, as confirmed in human single-nucleus RNA-seq data. Using two-sample Mendelian randomization, we nominated six differentially expressed genes (ATG16L2, ACSL5, MAP1LC3A, MAPKAPK3, PLXNB2, and SCFD1) within the significant pathways as relevant to ALS. We conclude that the disparate genetic etiologies of this fatal neurological disease converge on a smaller number of final common pathways and cell types.

Download Full-text

Shared genetic links between amyotrophic lateral sclerosis and obesity-related traits: a genome-wide association study

Neurobiology of Aging ◽

10.1016/j.neurobiolaging.2021.01.023 ◽

2021 ◽

Author(s):

Chunyu Li ◽

Ruwei Ou ◽

Qianqian Wei ◽

Huifang Shang

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Association Study ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Genome Wide ◽

A Genome ◽

Lateral Sclerosis ◽

Shared Genetic

Download Full-text

The Skeletal Muscle Emerges as a New Disease Target in Amyotrophic Lateral Sclerosis

Journal of Personalized Medicine ◽

10.3390/jpm11070671 ◽

2021 ◽

Vol 11 (7) ◽

pp. 671

Author(s):

Oihane Pikatza-Menoio ◽

Amaia Elicegui ◽

Xabier Bengoetxea ◽

Neia Naldaiz-Gastesi ◽

Adolfo López de Munain ◽

...

Keyword(s):

Skeletal Muscle ◽

Amyotrophic Lateral Sclerosis ◽

Muscle Tissue ◽

Motor Neurons ◽

Neurodegenerative Disorder ◽

Disease Onset ◽

Fine Tuning ◽

Current State ◽

The Central Nervous System ◽

Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder that leads to progressive degeneration of motor neurons (MNs) and severe muscle atrophy without effective treatment. Most research on ALS has been focused on the study of MNs and supporting cells of the central nervous system. Strikingly, the recent observations of pathological changes in muscle occurring before disease onset and independent from MN degeneration have bolstered the interest for the study of muscle tissue as a potential target for delivery of therapies for ALS. Skeletal muscle has just been described as a tissue with an important secretory function that is toxic to MNs in the context of ALS. Moreover, a fine-tuning balance between biosynthetic and atrophic pathways is necessary to induce myogenesis for muscle tissue repair. Compromising this response due to primary metabolic abnormalities in the muscle could trigger defective muscle regeneration and neuromuscular junction restoration, with deleterious consequences for MNs and thereby hastening the development of ALS. However, it remains puzzling how backward signaling from the muscle could impinge on MN death. This review provides a comprehensive analysis on the current state-of-the-art of the role of the skeletal muscle in ALS, highlighting its contribution to the neurodegeneration in ALS through backward-signaling processes as a newly uncovered mechanism for a peripheral etiopathogenesis of the disease.

Download Full-text

Cognitive dysfunction in amyotrophic lateral sclerosis: can we predict it?

Neurological Sciences ◽

10.1007/s10072-021-05188-0 ◽

2021 ◽

Author(s):

Fabiola De Marchi ◽

◽

Claudia Carrarini ◽

Antonio De Martino ◽

Luca Diamanti ◽

...

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Time Course ◽

Neurodegenerative Disorder ◽

Early Stage ◽

Multisystem Disorder ◽

Behavioral Impairment ◽

Behavioral Impairments ◽

Als Patients ◽

Disease Stages ◽

Lateral Sclerosis

Abstract Background and aim Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by the degeneration of both upper and lower motoneurons in the brain and spinal cord leading to motor and extra-motor symptoms. Although traditionally considered a pure motor disease, recent evidences suggest that ALS is a multisystem disorder. Neuropsychological alterations, in fact, are observed in more than 50% of patients: while executive dysfunctions have been firstly identified, alterations in verbal fluency, behavior, and pragmatic and social cognition have also been described. Detecting and monitoring ALS cognitive and behavioral impairment even at early disease stages is likely to have staging and prognostic implications, and it may impact the enrollment in future clinical trials. During the last 10 years, humoral, radiological, neurophysiological, and genetic biomarkers have been reported in ALS, and some of them seem to potentially correlate to cognitive and behavioral impairment of patients. In this review, we sought to give an up-to-date state of the art of neuropsychological alterations in ALS: we will describe tests used to detect cognitive and behavioral impairment, and we will focus on promising non-invasive biomarkers to detect pre-clinical cognitive decline. Conclusions To date, the research on humoral, radiological, neurophysiological, and genetic correlates of neuropsychological alterations is at the early stage, and no conclusive longitudinal data have been published. Further and longitudinal studies on easily accessible and quantifiable biomarkers are needed to clarify the time course and the evolution of cognitive and behavioral impairments of ALS patients.

Download Full-text

Genome-wide genetic links between amyotrophic lateral sclerosis and autoimmune diseases

BMC Medicine ◽

10.1186/s12916-021-01903-y ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Chun Yu Li ◽

Tian Mi Yang ◽

Ru Wei Ou ◽

Qian Qian Wei ◽

Hui Fang Shang

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Autoimmune Diseases ◽

Genetic Correlation ◽

Functional Enrichment ◽

Genome Wide Association Studies ◽

Risk Genes ◽

Genome Wide ◽

Shared Risk ◽

Lateral Sclerosis ◽

Shared Genetic

Abstract Background Epidemiological and clinical studies have suggested comorbidity between amyotrophic lateral sclerosis (ALS) and autoimmune disorders. However, little is known about their shared genetic architecture. Methods To examine the relation between ALS and 10 autoimmune diseases, including asthma, celiac disease (CeD), Crohn’s disease (CD), inflammatory bowel disease (IBD), multiple sclerosis (MS), psoriasis, rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), type 1 diabetes (T1D), and ulcerative colitis (UC), and identify shared risk loci, we first estimated the genetic correlation using summary statistics from genome-wide association studies, and then analyzed the genetic enrichment leveraging the conditional false discovery rate statistical method. Results We identified a significant positive genetic correlation between ALS and CeD, MS, RA, and SLE, as well as a significant negative genetic correlation between ALS and IBD, UC, and CD. Robust genetic enrichment was observed between ALS and CeD and MS, and moderate enrichment was found between ALS and UC and T1D. Thirteen shared genetic loci were identified, among which five were suggestively significant in another ALS GWAS, namely rs3828599 (GPX3), rs3849943 (C9orf72), rs7154847 (G2E3), rs6571361 (SCFD1), and rs9903355 (GGNBP2). By integrating cis-expression quantitative trait loci analyses in Braineac and GTEx, we further identified GGNBP2, ATXN3, and SLC9A8 as novel ALS risk genes. Functional enrichment analysis indicated that the shared risk genes were involved in four pathways including membrane trafficking, vesicle-mediated transport, ER to Golgi anterograde transport, and transport to the Golgi and subsequent modification. Conclusions Our findings demonstrate a specific genetic correlation between ALS and autoimmune diseases and identify shared risk loci, including three novel ALS risk genes. These results provide a better understanding for the pleiotropy of ALS and have implications for future therapeutic trials.

Download Full-text