口味偏好测定成人<em>果蝇</em
Summary
Taste is an important sensory process which facilitates attraction to beneficial substances and avoidance of toxic substances. This protocol describes a simple ingestion assay for determining Drosophila gustatory preference for a given chemical compound.
Abstract
Olfactory and gustatory perception of the environment is vital for animal survival. The most obvious application of these chemosenses is to be able to distinguish good food sources from potentially dangerous food sources. Gustation requires physical contact with a chemical compound which is able to signal through taste receptors that are expressed on the surface of neurons. In insects, these gustatory neurons can be located across the animal’s body allowing taste to play an important role in many different behaviors. Insects typically prefer compounds containing sugars, while compounds that are considered bitter tasting are avoided. Given the basic biological importance of taste, there is intense interest in understanding the molecular mechanisms underlying this sensory modality. We describe an adult Drosophila taste assay which reflects the preference of the animals for a given tastant compound. This assay may be applied to animals of any genetic background to examine the taste preference for a desired soluble compound.
Introduction
动物用chemosensation从不利条件，除了区分了有利条件。这种看法可能是这样的事情作为确定最好的食物来源，避免有毒物质或确定最佳的交配伙伴1关键。 Chemosensation通常分为两种感官部分：嗅觉和味觉的感官。这些感官的主要鉴别特征是，嗅觉（气味）被使用，而味觉（味道）需要与非易失性基板的身体接触来样周围的气态化学环境。这两种形式的感官刺激而被处理，并在大脑中产生相应的吸引力或排斥行为2解码神经系统的反应。这些感官因此对动物生存至关重要。
果蝇果蝇是不断增长的普及在了解使用模式生物ING昆虫如何感知气味和滋味。果蝇由于可用于分子，细胞，和行为途径的解剖遗传工具的丰富提供优于其他模型系统的巨大的优势。在过去15年的工作一直在表征特定细胞的身份，神经元受体和信号参与了嗅觉和味觉机制特别的工具。现在， 果蝇遗传学的功率被用来进一步阐明这些过程是如何在单个神经元和单电路级3-6编码。因此，它们提供了测定轻松打进改建感觉通路的读数是对这些字段的持续进步至关重要。
而大量的已知如何嗅觉信号进行编码并在大脑中处理的，要少得多理解有关在味觉通路类似的机制。我们在这里描述了可用于确定味道preferen一个协议行政长官在果蝇 ， 果蝇，像哺乳动物，一般喜欢甜味的化合物，而不是苦味化合物。这些食物源的任何组合可以在本实验设计来确定已知的遗传改变如何影响口味的选择可以利用。此外，药理学干预策略可以类似地评估其对动物的口味偏好效应。该测定的便利性和灵活性使得它有用的范例为理解在果蝇味觉感知的性质。
Protocol
Representative Results
Discussion
我们已经描述了一个简单而有效的协议，用于确定在果蝇味道偏好。在实验中经常使用这个实验版本，以确定感知不同品质（苦，甜，酸，咸和鲜味）呈味物质的味觉受体（GRS）的贡献。 果蝇基因组包含大约60个基因其通过选择性剪接8,9-编码68鉴定味觉受体。然而，其他蛋白质，如离子型谷氨酸受体和TRP通道也被证明在味道10-13中发挥作用。因此，在昆虫味道辨别能?…
Divulgazioni
The authors have nothing to disclose.
Acknowledgements
We would like to thank members of the Tessier lab for critical reading of this manuscript and helpful suggestions during the preparation of this protocol.
Materials
| Blue Food Coloring (Water, Propylene Glycol, FD&C Blue 1 and Red 40, Propylparaben) | McCormick | N/A | |
| Cryo/Freezer Boxes w/o Dividers | Fisher | 03-395-455 | |
| Dumont #5 Forceps | Fine Science Tools | 11251-20 | |
| Glacial Acetic Acid | Fisher | BP2401-500 | |
| Leica S6 E Stereozoom 0.63x-4.0x microscope | W. Nuhsbaum, Inc. | 10446294 | |
| Petri Dish (100 x 15 mm) | BD Falcon | 351029 | Reuseable if thoroughly washed and dried |
| Quick-Snap Microtubes | Alkali Scientific Inc. | C3017 | |
| Red Food Coloring (Water, Propylene Glycol, FD&C Reds 40 and 3, Propylparaben) | McCormick | N/A | |
| Sucrose | IBI Scientific | IB37160 |
Riferimenti
- Herrero, P. Fruit fly behavior in response to chemosensory signals. Peptides. 38 (2), 228-237 (2012).
- Vosshall, L. B., Stocker, R. F. Molecular architecture of smell and taste in Drosophila. Annu Rev Neurosci. 30, 505-533 (2007).
- Harris, D. T., Kallman, B. R., Mullaney, B. C., Scott, K. Representations of Taste Modality in the Drosophila Brain. Neuron. 86 (6), 1449-1460 (2015).
- Hong, E. J., Wilson, R. I. Simultaneous encoding of odors by channels with diverse sensitivity to inhibition. Neuron. 85 (3), 573-589 (2015).
- Kain, P., Dahanukar, A. Secondary taste neurons that convey sweet taste and starvation in the Drosophila brain. Neuron. 85 (4), 819-832 (2015).
- Masek, P., Worden, K., Aso, Y., Rubin, G. M., Keene, A. C. A dopamine-modulated neural circuit regulating aversive taste memory in Drosophila. Curr Biol. 25 (11), 1535-1541 (2015).
- Charlu, S., Wisotsky, Z., Medina, A., Dahanukar, A. Acid sensing by sweet and bitter taste neurons in Drosophila melanogaster. Nat Commun. 4, 2042 (2013).
- Clyne, P. J., Warr, C. G., Carlson, J. R. Candidate taste receptors in Drosophila. Science. 287 (5459), 1830-1834 (2000).
- Scott, K., et al. A chemosensory gene family encoding candidate gustatory and olfactory receptors in Drosophila. Cell. 104 (5), 661-673 (2001).
- Kim, S. H., et al. Drosophila TRPA1 channel mediates chemical avoidance in gustatory receptor neurons. Proc Natl Acad Sci U S A. 107 (18), 8440-8445 (2010).
- Koh, T. W., et al. The Drosophila IR20a clade of ionotropic receptors are candidate taste and pheromone receptors. Neuron. 83 (4), 850-865 (2014).
- Zhang, Y. V., Ni, J., Montell, C. The molecular basis for attractive salt-taste coding in Drosophila. Science. 340 (6138), 1334-1338 (2013).
- Zhang, Y. V., Raghuwanshi, R. P., Shen, W. L., Montell, C. Food experience-induced taste desensitization modulated by the Drosophila TRPL channel. Nat Neurosci. 16 (10), 1468-1476 (2013).
- Liman, E. R., Zhang, Y. V., Montell, C. Peripheral coding of taste. Neuron. 81 (5), 984-1000 (2014).
- Rodrigues, V., Cheah, P. Y., Ray, K., Chia, W. malvolio, the Drosophila homologue of mouse NRAMP-1 (Bcg), is expressed in macrophages and in the nervous system and is required for normal taste behaviour. EMBO J. 14 (13), 3007-3020 (1995).
- Tanimura, T., Isono, K., Yamamoto, M. T. Taste sensitivity to trehalose and its alteration by gene dosage in Drosophila melanogaster. Genetica. 119 (2), 399-406 (1988).
- Weiss, L. A., Dahanukar, A., Kwon, J. Y., Banerjee, D., Carlson, J. R. The molecular and cellular basis of bitter taste in Drosophila. Neuron. 69 (2), 258-272 (2011).
- French, A. S., et al. Dual mechanism for bitter avoidance in Drosophila. J Neurosci. 35 (9), 3990-4004 (2015).
- Deshpande, S. A., et al. Quantifying Drosophila food intake: comparative analysis of current methodology. Nat Methods. 11 (5), 535-540 (2014).
