This work is supported by a Canadian Health Research Institute (CIHR) Team Grant to Dr. Bolduc (co-PI) and Dr. Guy Rouleau (PI). We would like to thank Dr. Oksana Suchowersky, Dr. Kathryn Todd, the members of the University of Alberta fly club and Dr. Clayton Dickson for help in development of the method and statistical analysis.

Pesquisa sobre Drosophila melanogaster estava em conformidade com a Universidade de diretrizes de pesquisa de Alberta. 1. Fly Colecção <ol><li> Coletar 20 moscas usando CO 2 (g) anestesiados e coloque em um frasco de recolha 25 milímetros x 95 milímetros contendo alimentos. </li><li> Frascos contendo loja moscas horizontalmente para evitar a captura de moscas em quaisquer líquidos que podem se acumular no fundo do frasco. </li><li> Incubar moscas durante pelo menos 21 horas a 22 ° C em 45% de humidade num incubador durante aproximadamente durante 15 h. Defina a incubadora com uma luz de 12 horas: ciclo escuro. </li></ol> 2. Escalada Assay <ol><li> Na manhã seguinte, a transferência de 20 moscas a partir de um único frasco num copo de 250 ml cilindro graduado. Marque a posição do cilindro para mantê-lo todos os dias constante. Usar um cilindro de vidro por genótipo para evitar a contaminação cruzada entre os genótipos. Lavar-se ao fim de cada experiência e rolitar-los entre os genótipos. <ol><li> Conduzir as experiências em luz ambiente (ou luz vermelha se houver um defeito potencial na visão) a temperatura e humidade de 22 ° C e 40% respectivamente. Para evitar circadiano confundem ritmo, sempre realizar experimentos na mesma hora do dia. </li></ol></li><li> Selar o topo do cilindro com uma película de barreira (filme de cera) para impedir a fuga de quaisquer moscas (Figura 2). </li><li> Configure a câmera de vídeo em um tripé. Câmera com foco na linha 190 ml dos 250 ml cilindro graduado (17.5 cm). </li><li> Contar o número de moscas mortas na parte inferior do cilindro e nos frascos de alimentos. Grave este número como a mortalidade. </li><li> Muito bata levemente contra o cilindro de uma almofada de espuma de células fechadas, repetidamente, com força suficiente para deslocar as moscas para a superfície de fundo interna. Toque 5-10 vezes enquanto com a outra mão para pressionar registro na câmera. </li><li> Pressione o botão &quot;Record&quot; na câmara. </li><li> Comece o vidEO gravação e câmera toque no cilindro de seis vezes em um padrão não-rítmica distinta. </li><li> Realizar cada julgamento por 2 min do tempo as moscas estão último aproveitado e registrar o número de moscas que atravessam a altura de 17,5 centímetros (190 ml) em cada ponto de tempo escolhido (quantificar a cada 10 segundos). Nota: A marcação no cilindro ml irá variar de um modelo para outro cilindro, dependendo do diâmetro. Para evitar erros, medir a altura de cada cilindro usado. </li><li> Uma vez que o julgamento terminou, dispor de moscas em 95% de etanol. </li><li> Repita os passos 2.1 a 2.9 até que todos os replicados foram testados com moscas fresco de cada vez. Nota: Embora cinco repetições pode ser suficiente, com uma mutação ter um forte efeito na locomoção, 10 réplicas biológicas de 20 moscas, moscas (200) é recomendado para detectar diferenças menores. </li><li> Após a conclusão da experiência, os cilindros de lavagem na máquina de lavar de laboratório e seca O / N para ser re-utilizado. </li></ol> 3. Análise <ol><li> Analyvídeos ze de cada voar julgamento. Cada 10 segundos, anotar o número total de moscas que passam a linha de meta. <ol><li> Se uma mosca sobe de volta para baixo ou cai, registro que voam como -1 e contar a próxima mosca para cruzar a linha de meta como o mesmo número que a mosca que subiu de volta para baixo ou caiu. Por exemplo, se o 15º mosca cai abaixo da linha de meta, a próxima mosca para cruzar a linha (16 th voar) é considerado o 15º mosca e não o 16º. </li></ol></li><li> Subtrair a mortalidade a partir do número total de moscas (20) para se obter o número de moscas que permanecem no ensaio. Em cada ponto de tempo, obter a fracção de moscas acima da linha de destino. </li><li> Traçar cada porcentagem em cada ponto de tempo (ver Figura 3). </li><li> Analisar o desempenho no ponto de dados 120 segundos e realizar teste t de Student quando dois grupos se encontrem presentes ou análise de variância e um pós-teste para comparações múltiplas (com modificação Bonferroni para planejado e Tukey para co não planejadamparisons). O teste de Kolmogorov-Smirnov testa 17 também é realizada para verificar a normalidade e variância igual, mas também para comparar as distribuições do grupo mutante para o controlo. </li><li> Para apresentar os dados sobre o envelhecimento, plotar a porcentagem de moscas subir a 120 segundos com moscas de diferentes idades (2 dias, uma semana, duas semanas) para ver se há um déficit progressivo (Figura 4). </li></ol>

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The authors have nothing to disclose.

Drosophila já provou ser um excelente modelo de doença 14 e outras condições neurodegenerativas 1,2 de Parkinson. Além das ferramentas genéticas disponíveis em Drosophila, o seu genoma é altamente conservada em genes envolvidos em desordens neurológicas 19. O advento da largura métodos de rastreio genético do genoma (incluindo exome sequenciamento completo) é provável que continue a fornecer uma lista maior de genes candidatos associados com distúrbios do ...

Doenças neurodegenerativas tais como a doença devastadora de Parkinson, esclerose lateral amiotrófica, e paraplegia espástica hereditária são cada vez mais reconhecidas. Infelizmente, a maioria desses distúrbios neurodegenerativos são ainda sem tratamentos. O uso clínico generalizado de testes genéticos, imparciais de todo o genoma, tais como sequenciação de toda exome levou a um aumento do número de genes implicados em distúrbios locomotiva humanos. Apesar deste progresso, a progressão patológica desde cedo a fases tardias, permanece indefinida nesses transtornos. Drosophila fornece um com as ferramentas genéticas para estudar exigência gene de uma forma temporal e espacial controlada. Além disso, Drosophila tem se mostrado útil na triagem de drogas para doenças neurológicas como Parkinson 1, a doença de Alzheimer 2, deficiência mental e epilepsia 3,4 5,6 entre outros. O nosso objectivo foi desenvolver um custo eficaze ensaio de confiança que permita a análise de alto rendimento que ainda seria suficientemente sensível para detectar pequenas mudanças no desempenho do motor. Existem vários ensaios utilizados para quantificar os efeitos da mutação genética e / ou condições ambientais sobre o comportamento de escalada de Drosophila. A maioria dos ensaios capitalizar a tendência natural das moscas para escalar, conhecidos como geotaxis negativos, ou o ensaio de escalada. Benzer 7 em 1967 sugeriram que o aparelho em contracorrente utilizada para o estudo de fototaxia também poderia ser usado para estudar gravitaxis. Desde então, Ganetsky 8 e muitos outros 9 -12 construíram no ensaio inicial. O princípio é o de colocar um número conhecido de moscas em um frasco e o frasco toque fortemente contra uma superfície dura, fazendo com que as moscas a cair para o fundo do frasco. Como se trata de um comportamento inato, as moscas vai tentar subir para a parte superior do frasco, em oposição à gravidade. Este ensaio é quantitativa e measures quantas moscas subiram passado um marcador no frasco durante um período de tempo estipulado. Medição da velocidade, em vez do número total de moscas escalada tornou-se um parâmetro fiável e mostrado defeitos nos casos em que o número de parâmetros de moscas não foi significativa 13. O ensaio de escalada provou ser útil no estudo de muitas doenças neurodegenerativas, incluindo a doença de Parkinson 14. No entanto, observou-se que os defeitos locomotiva pode não ser detectável no momento em que a neurodegeneração já é visto em estudos patológicos 14. Assim, a utilização do ensaio tradicional pode limitar a capacidade para estudar os estágios iniciais da patogénese da doença. O aparecimento de defeitos locomotiva durante fases posteriores da patologia pode refletir uma doença cuja progressão é muito avançado para resgate completo. Isto levanta um problema potencial com a sensibilidade do ensaio escalada tradicional. A incapacidade potencial do tradicional subir ensaio para detectar defeitos leves locomotiva pode ser atribuído à altura a que as moscas são obrigados a subir. Os tradicionais 15,16 ensaio mede o número de moscas para escalar com sucesso através de uma altura de 2 a 5 cm em 10 a 20 seg.

<table><tbody><tr><td>Drosophila stocks</td><td></td><td></td><td>The stocks are selected depending on the experiments. The temperature and humidity in the room and in the incubator must be controled and consistent to avoid flies being too staticky or too wet.</td></tr><tr><td>Video camera</td><td></td><td></td><td>Any digital camcorder will do. Make sure they can focus on close object.</td></tr><tr><td>Graduated cylinder</td><td>Kimble</td><td>20028W</td><td>Different models of graduated cylinder may have different diameter. It is therefore imporant to measure the height.</td></tr><tr><td>Computer</td><td></td><td></td><td>Any model will do. We used the computer to monitor the climbing of the flies and record the number of flies at each time point.</td></tr></tbody></table>

quantitative analysis of climbing defects in a drosophila model of neurodegenerative disorders

Locomotiva defeitos resultantes de doenças neurodegenerativas pode ser um início dos sintomas da doença de tarde, após anos de degeneração subclínica, e, assim, estratégias atuais de tratamento terapêutico não são curativos. Através da utilização de sequenciação exome conjunto, um número cada vez maior de genes foram identificados a desempenhar um papel na locomoção humana. Apesar de identificar estes genes, não se sabe como esses genes são cruciais para o funcionamento normal locomotiva. Por conseguinte, um ensaio de confiança, que utiliza organismos modelo para elucidar o papel destes genes, a fim de identificar novos alvos de interesse terapêutico, é necessário mais do que nunca. Nós preparámos uma versão sensibilizado do ensaio geotaxis negativos que permite a detecção de defeitos leves anterior e tem a capacidade de avaliar esses defeitos ao longo do tempo. O ensaio é realizado em um cilindro de vidro graduado, que é selada com uma película de barreira de cera. Ao aumentar a distância patamar de ser escalado para 17,5 cm e aumentando a duração da experiência para 2 min temos observado uma maior sensibilidade na detecção de disfunções de mobilidade suaves. O ensaio é rentável e não requer a formação extensa para obter resultados altamente reprodutíveis. Isso o torna uma excelente técnica para o rastreio de drogas candidatas em mutantes de Drosophila com defeitos de locomoção.

Escalada é um comportamento forte e reprodutível. Na verdade, um dia velhos moscas do tipo selvagem alcançar o desempenho escalada distância do alvo rapidamente (25-30 seg). Moscas mutantes apresentam uma série de desempenho de leve (ou retardada) para completar a incapacidade de subir ao alvo. Nós ilustramos esta aqui com dois alelos mutantes diferentes. O primeiro é um alelo grave do Spastin gene causada por uma deleção completa do gene Spastin spas (5,75) 18. Nesta linha (5,75 spas com ...

Watch this Scientific Journal Video about Quantitative Analysis of Climbing Defects in a Drosophila Model of Neurodegenerative Disorders at JoVE.com

Quantitative Analysis of Climbing Defects in a Drosophila Model of Neurodegenerative Disorders

We present an optimized inexpensive and reliable negative geotaxis assay in Drosophila melanogaster as a model for neurodegenerative disorders. Being more sensitive to mild locomotor defects, this assay will help screen for potential genetic interactions and drug targets.

Análise Quantitativa de Defeitos de escalada em um modelo de Drosophila de doenças neurodegenerativas

Locomotive defects resulting from neurodegenerative disorders can be a late onset symptom of disease, following years of subclinical degeneration, and ...

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Universidad de Cartagena UDEC

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Neuroscience

18.5K visualizações.  University of Alberta. We present an optimized inexpensive and reliable negative geotaxis assay in Drosophila melanogaster as a model for neurodegenerative disorders. Being more sensitive to mild locomotor defects, this assay will help screen for potential genetic interactions and drug targets. 

Vídeo: Quantitative Analysis of Climbing Defects in a Drosophila Model of Neurodegenerative Disorders

Assaying Locomotor, Learning, and Memory Deficits in Drosophila Models of Neurodegeneration

Advances in genetic methods have enabled the study of genes involved in human neurodegenerative diseases using Drosophila as a model system1. Most of these diseases, including Alzheimer's, Parkinson's and Huntington's disease are characterized by age-dependent deterioration in learning and memory functions and movement coordination2. Here we use behavioral assays, including the negative geotaxis assay3 and the aversive phototaxic suppression assay (APS assay)4,5, to show that some of the behavior characteristics associated with human neurodegeneration can be recapitulated in flies. In the negative geotaxis assay, the natural tendency of flies to move against gravity when agitated is utilized to study genes or conditions that may hinder locomotor capacities. In the APS assay, the learning and memory functions are tested in positively-phototactic flies trained to associate light with aversive bitter taste and hence avoid this otherwise natural tendency to move toward light. Testing these trained flies 6 hours post-training is used to assess memory functions. Using these assays, the contribution of any genetic or environmental factors toward developing neurodegeneration can be easily studied in flies.

Assaying Locomotor, Learning, and Memory Deficits in Drosophila Models of Neurodegeneration

Behavior assays for measuring locomotor functions, learning, and memory abilities in Drosophila.

Locomotor ensaio, Aprendizagem e Memória Os déficits no Drosophila Modelos de neurodegeneração

Advances in genetic methods have enabled the study of genes involved in human neurodegenerative diseases using Drosophila as a model system1. Most of ...

Neurociência

In Vivo Forward Genetic Screen to Identify Novel Neuroprotective Genes in Drosophila melanogaster

There is much to understand about the onset and progression of neurodegenerative diseases, including the underlying genes responsible. Forward genetic screening using chemical mutagens is a useful strategy for mapping mutant phenotypes to genes among Drosophila and other model organisms that share conserved cellular pathways with humans. If the mutated gene of interest is not lethal in early developmental stages of flies, a climbing assay can be conducted to screen for phenotypic indicators of decreased brain functioning, such as low climbing rates. Subsequently, secondary histological analysis of brain tissue can be performed in order to verify the neuroprotective function of the gene by scoring neurodegeneration phenotypes. Gene mapping strategies include meiotic and deficiency mapping that rely on these same assays can be followed by DNA sequencing to identify possible nucleotide changes in the gene of interest.

In Vivo Forward Genetic Screen to Identify Novel Neuroprotective Genes in Drosophila melanogaster

We present a protocol using a forward genetic approach to screen for mutants exhibiting neurodegeneration in Drosophila melanogaster. It incorporates a climbing assay, histology analysis, gene mapping and DNA sequencing to ultimately identify novel genes related to the process of neuroprotection.

In vivo Forward genética Screen para identificar novos genes neuroprotetores em Drosophila melanogaster

There is much to understand about the onset and progression of neurodegenerative diseases, including the underlying genes responsible. Forward genetic ...

Genética

An Automated Rapid Iterative Negative Geotaxis Assay for Analyzing Adult Climbing Behavior in a Drosophila Model of Neurodegeneration

Neurodegenerative diseases are frequently associated with a progressive loss of movement ability, reduced life span, and age-dependent neurodegeneration. To understand the mechanism of these cellular events, and their causal relationships with each other, Drosophila melanogaster, with its sophisticated genetic tools and diverse behavioral features, are used as disease models for assessing neurodegenerative phenotypes. Here we describe a high-throughput method to analyze Drosophila adult negative geotaxis behavior, as an indication for possible motor defects associated with neurodegeneration. An automated machine is designed and developed to drive fly synchronization using an initial electric impulse, later allowing the recording of negative geotaxis behavior over a course of secs to mins. Images from the digitally recorded video are then processed with the self-designed RflyDetection software for statistical data manipulation. Different from the manually controlled negative geotaxis assay based on single fly, this precise, fast, and high-throughput protocol allows data acquisition from more than hundreds of flies simultaneously, providing an efficient approach to advance our understanding in the underlying mechanism of locomotor deficits associated with neurodegeneration.

An Automated Rapid Iterative Negative Geotaxis Assay for Analyzing Adult Climbing Behavior in a Drosophila Model of Neurodegeneration

This step-by-step protocol analyzes Drosophila negative geotaxis behavior using an automated multi-cylinder system that hosts hundreds of flies and synchronizes their action by an electric motor. Upon synchronization, fly negative geotaxis behavior is assayed, digitally recorded, and analyzed using the self-designed RflyDetection software.

Um ensaio automatizado rápida iterativo Geotaxis negativo para analisar o comportamento de adultos de escalada em um modelo de drosófila de neurodegeneração

Neurodegenerative diseases are frequently associated with a progressive loss of movement ability, reduced life span, and age-dependent neurodegeneration. ...

Comportamento

Assessing Neurodegenerative Phenotypes in Drosophila Dopaminergic Neurons by Climbing Assays and Whole Brain Immunostaining

Drosophila melanogaster is a valuable model organism to study aging and pathological degenerative processes in the nervous system. The advantages of the fly as an experimental system include its genetic tractability, short life span and the possibility to observe and quantitatively analyze complex behaviors. The expression of disease-linked genes in specific neuronal populations of the Drosophila brain, can be used to model human neurodegenerative diseases such as Parkinson's and Alzheimer's 5.
Dopaminergic (DA) neurons are among the most vulnerable neuronal populations in the aging human brain. In Parkinson's disease (PD), the most common neurodegenerative movement disorder, the accelerated loss of DA neurons leads to a progressive and irreversible decline in locomotor function. In addition to age and exposure to environmental toxins, loss of DA neurons is exacerbated by specific mutations in the coding or promoter regions of several genes. The identification of such PD-associated alleles provides the experimental basis for the use of Drosophila as a model to study neurodegeneration of DA neurons in vivo. For example, the expression of the PD-linked human &alpha;-synuclein gene in Drosophila DA neurons recapitulates some features of the human disease, e.g. progressive loss of DA neurons and declining locomotor function 2. Accordingly, this model has been successfully used to identify potential therapeutic targets in PD 8.
Here we describe two assays that have commonly been used to study age-dependent neurodegeneration of DA neurons in Drosophila: a climbing assay based on the startle-induced negative geotaxis response and tyrosine hydroxylase immunostaining of whole adult brain mounts to monitor the number of DA neurons at different ages. In both cases, in vivo expression of UAS transgenes specifically in DA neurons can be achieved by using a tyrosine hydroxylase (TH) promoter-Gal4 driver line 3, 10.

Assessing Neurodegenerative Phenotypes in Drosophila Dopaminergic Neurons by Climbing Assays and Whole Brain Immunostaining

Here we describe two assays that have been established to study age-dependent neurodegeneration of dopaminergic (DA) neurons in Drosophila: the climbing/startle-induced negative geotaxis assay which allows to study the functional effects of DA neurons degeneration and the tyrosine hydroxylase immunostaining which is used to identify and count DA neurons in whole brain mounts.

Avaliando fenótipos Neurodegenerativas em<em&gt; Drosophila</em&gt; Neurônios dopaminérgicos subindo Ensaios e toda Imunocoloração Cérebro

Drosophila melanogaster is a valuable model organism to study aging and pathological degenerative processes in the nervous system. The advantages of the ...

A Simple Technique to Assay Locomotor Activity in Drosophila

Drosophila melanogaster is an ideal model organism for studying various diseases due to its abundance of advanced genetic manipulation techniques and diverse behavioral features. Identifying behavioral deficiency in animal models is a crucial measure of disease severity, for example, in neurodegenerative diseases where patients often experience impairments in motor function. However, with the availability of various systems to track and assess motor deficits in fly models, such as drug-treated or transgenic individuals, an economical and user-friendly system for precise evaluation from multiple angles is still lacking. A method based on the AnimalTracker application programming interface (API) is developed here, which is compatible with the Fiji image processing program, to systematically evaluate the movement activities of both adult and larval individuals from recorded video, thus allowing for the analysis of their tracking behavior. This method requires only a high-definition camera and a computer peripheral hardware integration to record and analyze behavior, making it an affordable and effective approach for screening fly models with transgenic or environmental behavioral deficiencies. Examples of behavioral tests using pharmacologically treated flies are given to show how the techniques can detect behavioral changes in both adult flies and larvae in a highly repeatable manner.

A Simple Technique to Assay Locomotor Activity in Drosophila

The present protocol assesses the locomotor activity of Drosophila by tracking and analyzing the movement of flies in a hand-made arena using open-source software Fiji, compatible with plugins to segment pixels of each frame based on high-definition video recording to calculate parameters of speed, distance, etc.

Uma técnica simples para avaliar a atividade locomotora em Drosophila

Drosophila melanogaster is an ideal model organism for studying various diseases due to its abundance of advanced genetic manipulation techniques and ...

Mass Histology to Quantify Neurodegeneration in Drosophila

Progressive neurodegenerative diseases like Alzheimer&#39;s disease (AD) or Parkinson&#39;s disease (PD) are an increasing threat to human health worldwide. Although mammalian models have provided important insights into the underlying mechanisms of pathogenicity, the complexity of mammalian systems together with their high costs are limiting their use. Therefore, the simple but well-established Drosophila model-system&#160;provides an alternative for investigating the molecular pathways that are affected in these diseases. Besides behavioral deficits, neurodegenerative diseases are characterized by histological phenotypes such as neuronal death and axonopathy. To quantify neuronal degeneration and to determine how it is affected by genetic and environmental factors, we use a histological approach that is based on measuring the vacuoles in adult fly brains. To minimize the effects of systematic error and to directly compare sections from control and experimental flies in one preparation, we use the &#39;collar&#39; method for paraffin sections. Neurodegeneration is then assessed by measuring the size and/or number of vacuoles that have developed in the fly brain. This can either be done by focusing on a specific region of interest or by analyzing the entire brain by obtaining serial sections that span the complete head. Therefore, this method allows one to measure not only severe degeneration but also relatively mild phenotypes that are only detectable in a few sections, as occurs during normal aging.

Mass Histology to Quantify Neurodegeneration in Drosophila

Drosophila is widely used as a model system to study neurodegeneration. This protocol describes a method by which degeneration, as determined by vacuole formation in the brain, can be quantified. It also minimizes effects due to the experimental procedure by processing and sectioning control and experimental flies as one sample.

Mass Histologia para quantificar neurodegeneração em<em&gt; Drosophila</em

Progressive neurodegenerative diseases like Alzheimer&#39;s disease (AD) or Parkinson&#39;s disease (PD) are an increasing threat to human health ...

Quantitative Analysis of Neuronal Dendritic Arborization Complexity in Drosophila

Dendrites are the branched projections of a neuron, and dendritic morphology reflects synaptic organization during the development of the nervous system. Drosophila larval neuronal dendritic arborization (da) is an ideal model for studying morphogenesis of neural dendrites and gene function in the development of nervous system. There are four classes of da neurons. Class IV is the most complex with a branching pattern that covers almost the entire area of the larval body wall. We have previously characterized the effect of silencing the Drosophila ortholog of SOX5 on class IV neuronal dendritic arborization complexity (NDAC) using four parameters: the length of dendrites, the surface area of dendrite coverage, the total number of branches, and the branching structure. This protocol presents the workflow of NDAC quantitative analysis, consisting of larval dissection, confocal microscopy, and image analysis procedures using ImageJ software. Further insight into da neuronal development and its underlying mechanisms will improve the understanding of neuronal function and provide clues about the fundamental causes of neurological and neurodevelopmental disorders.

Quantitative Analysis of Neuronal Dendritic Arborization Complexity in Drosophila

This protocol focuses on quantitative analysis of neuronal dendritic arborization complexity (NDAC) in Drosophila, which can be used for studies of dendritic morphogenesis.

Análise quantitativa da arborização dendrítica Neuronal complexidade em Drosophila

Dendrites are the branched projections of a neuron, and dendritic morphology reflects synaptic organization during the development of the nervous system. ...

Quantitative Cell Biology of Neurodegeneration in Drosophila Through Unbiased Analysis of Fluorescently Tagged Proteins Using ImageJ

With the rising prevalence of neurodegenerative diseases, it is increasingly important to understand the underlying pathophysiology that leads to neuronal dysfunction and loss. Fluorescence-based imaging tools and technologies enable unprecedented analysis of subcellular neurobiological processes, yet there is still a need for unbiased, reproducible, and accessible approaches for extracting quantifiable data from imaging studies. We have developed a simple and adaptable workflow to extract quantitative data from fluorescence-based imaging studies using Drosophila models of neurodegeneration. Specifically, we describe an easy-to-follow, semi-automated approach using Fiji/ImageJ to analyze two cellular processes: first, we quantify protein aggregate content and profile in the Drosophila optic lobe using fluorescent-tagged mutant huntingtin proteins; and second, we assess autophagy-lysosome flux in the Drosophila visual system with ratiometric-based quantification of a tandem fluorescent reporter of autophagy. Importantly, the protocol outlined here includes a semi-automated segmentation step to ensure all fluorescent structures are analyzed to minimize selection bias and to increase resolution of subtle comparisons. This approach can be extended for the analysis of other cell biological structures and processes implicated in neurodegeneration, such as proteinaceous puncta (stress granules and synaptic complexes), as well as membrane-bound compartments (mitochondria and membrane trafficking vesicles). This method provides a standardized, yet adaptable reference point for image analysis and quantification, and could facilitate reliability and reproducibility across the field, and ultimately enhance mechanistic understanding of neurodegeneration.

Quantitative Cell Biology of Neurodegeneration in Drosophila Through Unbiased Analysis of Fluorescently Tagged Proteins Using ImageJ

We have developed a simple and adaptable workflow to extract quantitative data from fluorescence-imaging-based cell biological studies of protein aggregation and autophagic flux in the central nervous system of Drosophila models of neurodegeneration.

Biologia celular quantitativa de neurodegeneração em Drosophila , através de uma análise imparcial das proteínas fluorescente etiquetadas usando o ImageJ

With the rising prevalence of neurodegenerative diseases, it is increasingly important to understand the underlying pathophysiology that leads to neuronal ...

Purification of Transcripts and Metabolites from Drosophila Heads

For the last decade, we have tried to understand the molecular and cellular mechanisms of neuronal degeneration using Drosophila as a model organism. Although fruit flies provide obvious experimental advantages, research on neurodegenerative diseases has mostly relied on traditional techniques, including genetic interaction, histology, immunofluorescence, and protein biochemistry. These techniques are effective for mechanistic, hypothesis-driven studies, which lead to a detailed understanding of the role of single genes in well-defined biological problems. However, neurodegenerative diseases are highly complex and affect multiple cellular organelles and processes over time. The advent of new technologies and the omics age provides a unique opportunity to understand the global cellular perturbations underlying complex diseases. Flexible model organisms such as Drosophila are ideal for adapting these new technologies because of their strong annotation and high tractability. One challenge with these small animals, though, is the purification of enough informational molecules (DNA, mRNA, protein, metabolites) from highly relevant tissues such as fly brains. Other challenges consist of collecting large numbers of flies for experimental replicates (critical for statistical robustness) and developing consistent procedures for the purification of high-quality biological material. Here, we describe the procedures for collecting thousands of fly heads and the extraction of transcripts and metabolites to understand how global changes in gene expression and metabolism contribute to neurodegenerative diseases. These procedures are easily scalable and can be applied to the study of proteomic and epigenomic contributions to disease.

Purification of Transcripts and Metabolites from Drosophila Heads

We describe here the procedures for the extraction and purification of mRNA and metabolites from Drosophila heads. We are applying these techniques to better understand the cellular perturbations underlying neuronal degeneration. These methodologies can be easily scaled and adapted for other "omic" projects.

Purificação de Transcrições e metabolitos de<em&gt; Drosophila</em&gt; Cabeças

For the last decade, we have tried to understand the molecular and cellular mechanisms of neuronal degeneration using Drosophila as a model organism. ...

Biologia

Visualizing Synaptic Degeneration in Adult Drosophila in Association with Neurodegeneration

Drosophila serves as a useful model for assessing synaptic structure and function associated with neurodegenerative diseases. While much work has focused on neuromuscular junctions (NMJs) in Drosophila larvae, assessing synaptic integrity in adult Drosophila has received much less attention. Here we provide a straightforward method for dissection of the dorsal longitudinal muscles (DLMs), which are required for flight ability. In addition to flight as a behavioral readout, this dissection allows for the both DLM synapses and muscle tissue to be amenable to structural analysis using fluorescently labeled antibodies for synaptic markers or proteins of interest. This protocol allows for the evaluation of the structural integrity of synapses in adult Drosophila during aging to model the progressive, age-dependent nature of most neurodegenerative diseases.

Visualizing Synaptic Degeneration in Adult Drosophila in Association with Neurodegeneration

The goal of this procedure is to dissect the dorsal longitudinal muscle (DLM) tissue to assess the structural integrity of DLM neuromuscular junctions (NMJs) in neurodegenerative disease models using Drosophila melanogaster.

Visualização da Degeneração Sináptica em Drosophila Adulta em Associação com Neurodegeneração

Drosophila serves as a useful model for assessing synaptic structure and function associated with neurodegenerative diseases. While much work has focused ...

Análise Quantitativa de Defeitos de escalada em um modelo de Drosophila de doenças neurodegenerativas

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