Препарирование и обработка изображений активных зон в Drosophila Нервно-мышечном соединении
Summary
Нервно-мышечном соединении (NMJ) из<em> Дрозофилы</em> Является важной модельной системой для изучения нормальной синаптической функции, а также возмущения в синаптической функции найдены в некоторых неврологических заболеваний. Мы представляем протокол вскрытия<em> Drosophila</em> Личиночной-двигательного аппарата и иммуногистохимическое активных белков зоны в NMJ.
Abstract
The Drosophila larvae neuromuscular junction (NMJ) is an excellent model for the study of synaptic structure and function. Drosophila is well known for the ease of powerful genetic manipulations and the larval nervous system has proven particularly useful in studying not only normal function but also perturbations that accompany some neurological disease (Lloyd and Taylor, 2010). Many key synaptic molecules found in Drosophila are also found in mammals and like most CNS excitatory synapses in mammals, the Drosophila NMJ is glutamatergic and demonstrates activity-dependent remodeling (Kohet al. , 2000). Additionally, Drosophila neurons can be individually identified because their innervation patterns are stereotyped and repetitive making it possible to study identified synaptic terminals, such as those between motor neurons and the body-wall muscle fibers that they innervate (Keshishian and Kim, 2004). The existence of evolutionarily conserved synapse components along with the ease of genetic and physical manipulation make the Drosophila model ideal for investigating the mechanisms underlying synaptic function (Budnik, 1996).
The active zones at synaptic terminals are of particular interest because these are the sites of neurotransmitter release. NC82 is a monoclonal antibody that recognizes the Drosophila protein Bruchpilot (Brp), a CAST1/ERC family member that is an important component of the active zone (Waghet al. , 2006). Brp was shown to directly shape the active zone T-bar and is responsible for effectively clustering Ca2+ channels beneath the T-bar density (Fouquetet al. , 2009). Mutants of Brp have reduced Ca2+ channel density, depressed evoked vesicle release, and altered short-term plasticity (Kittelet al. , 2006). Alterations to active zones have been observed in Drosophila disease models. For example, immunofluorescence using the NC82 antibody showed that the active zone density was decreased in models of amyotrophic lateral sclerosis and Pitt-Hopkins syndrome (Ratnaparkhiet al. , 2008; Zweieret al. , 2009). Thus, evaluation of active zones, or other synaptic proteins, in Drosophila larvae models of disease may provide a valuable initial clue to the presence of a synaptic defect.
Preparing whole-mount dissected Drosophila larvae for immunofluorescence analysis of the NMJ requires some skill, but can be accomplished by most scientists with a little practice. Presented is a method that provides for multiple larvae to be dissected and immunostained in the same dissection dish, limiting environmental differences between each genotype and providing sufficient animals for confidence in reproducibility and statistical analysis.
Protocol
Discussion
Для нейронов, синаптических площадь терминала имеет решающее значение, и является мостом для надлежащей связи между пост-и пресинаптических клетках. Эффективный способ исследовать здоровье нейронов при болезни моделей для анализа белков синаптических терминала иммунофлюоресценции…
Divulgazioni
The authors have nothing to disclose.
Acknowledgements
Мы благодарим доктора Nael Алами и доктор Нам Чул Ким за полезные комментарии об этой рукописи.
Materials
| Name of Reagent | Company | Catalogue Number | Comments |
| Sylgard 184 Silicone Elastomer Base | Dow Corning | 68037-59-2 | After mixing allow for bubbles to rise slowly out by putting on slow rotator or allowing to sit for 30 minutes or more. |
| Stainless Steel Minutien PIns | Fine Science Tools | 26002-10 | Trim to approx. 3-4mm in length with regular scissors |
| Laminectomy Forceps (Blunt- Used for grasping pins) | Fine Science tools | 11223-20 | Use as blunt forceps for grasping pins |
| Dissection Forceps | World Precision Instruments | 501985 | |
| SuperFine Vannas Scissors, 8cm long | World Precision Instruments | 501778 | |
| Mouse anti-Brp antibody | DSHB | NC82 | Use 1:50 dilution |
| Cy3 Affinipure Goat Anti-Horseradish Peroxidase | Jackson Immunoresearch | 123-165-021 | Use at 1:200 dilution |
| Alexa Fluor 488 Goat anti-Mouse IgG | Invitrogen | A11001 | Use approx. 1:200 dilution |
Riferimenti
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