Condicionamento positivo à butanona em c. elegans: padronização do protocolo de aprendizagem associativa
Data
2022
Autores
Silva, Luiz Felipe Marquês da 
Orientadores
Mello, Luiz Eugênio Araújo de Moraes
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Introdução: O C. elegans é um organismo modelo que vem cada vez mais ganhando
notoriedade no meio acadêmico, pois é muito útil para o estudo do aprendizado e da
memória em níveis celular e molecular. Desta forma, este projeto visou por incluir o C.
elegans no acervo de espécies do grupo LE MELLO e inaugurar o estudo de sua
aprendizagem no continente latino-americano. Objetivos: Implementar e adaptar um
modelo de condicionamento positivo em C. elegans e investigar o seu processo de
aprendizagem associativa. Materiais e métodos: Vermes hermafroditas da cepa
selvagem (N2 Bristol) foram cultivos a 20º C em placas de petri com meio NGM e
semeadas com E. coli HT115 ou OP50-1 em condição ad libitum até o primeiro dia da
fase adulta. O aprendizado nos animais foi induzido através de um modelo de
condicionamento apetitivo a odor e avaliado por meio de ensaio de quimiotaxia. Os
períodos de retenção empregados no projeto foram: 0, 15, 30, 60, 120, 180, 210, 300
e 1440 minutos. A padronização do modelo de aprendizagem foi executada através do
uso de placas personalizadas com adesivo para os ensaios de quimiotaxia e cultura
bacteriana concentrada para a alimentação dos nematoides. Resultados: O perfil de
aprendizagem caracterizado com E. coli HT115 no projeto revelou ser mais crônico que
o estabelecido pela literatura com a cepa OP50. Os dados dos ensaios executados com
E. coli OP50-1 tiveram alta variabilidade, contudo aparentam seguir a tendência
prevista pela literatura. Para agilizar a contagem dos vermes nas fotografias dos
ensaios, uma aplicação web foi desenvolvida para a semi-automação do processo.
Conclusão: A dieta oferecida ao C. elegans, possivelmente, tem impacto sobre a sua
capacidade de aprendizagem e de formação de memória associativa, devido as
diferenças constitutivas e metabólicas existentes entre os microrganismos ofertados e
suas variadas cepas.
Introduction: The worm C. elegans is a model organism that is increasing in notoriety in the academic environment, as it is very useful to study of learning and memory at the cellular and molecular levels. Therefore, this project aimed to include the C. elegans in the species' collection of the LE MELLO group and to inaugurate the study of its learning in the Latin American continent. Objectives: Implement and adapt a positive conditioning model in C. elegans and investigate its associative learning. Materials and Methods: Wild-type hermaphrodite worms (N2 Bristol) were cultured at 20°C to adulthood on NGM seeded with E. coli HT115 or OP50-1 in ad libitum using petri plates. Learning in the animals was induced through an appetitive conditioning model for odor and evaluated by chemotaxis assay. The hold periods employed in the project were: 0, 15, 30, 60, 120, 180, 210, 300 and 1440 minutes. Standardization of the learning model was performed by using custom plates with sticker to the chemotaxis assays and concentrated bacterial culture to feeding the nematodes. Results: The learning pattern characterized with E. coli HT115 in the project was found to be more chronic than that established in the reference with the OP50 strain. Data from assays performed with E. coli OP50-1 manifested high variability, however they seem to follow the trend predicted by the reference. To improve the counting of worms in the assays' pictures, a web application was developed for the semi-automation of the process. Conclusion: The diet offered to C. elegans, possibly, affects its learning and its formation of associative memories, due to the constitutive and metabolic differences between the microorganisms offered and their distinct strains.
Introduction: The worm C. elegans is a model organism that is increasing in notoriety in the academic environment, as it is very useful to study of learning and memory at the cellular and molecular levels. Therefore, this project aimed to include the C. elegans in the species' collection of the LE MELLO group and to inaugurate the study of its learning in the Latin American continent. Objectives: Implement and adapt a positive conditioning model in C. elegans and investigate its associative learning. Materials and Methods: Wild-type hermaphrodite worms (N2 Bristol) were cultured at 20°C to adulthood on NGM seeded with E. coli HT115 or OP50-1 in ad libitum using petri plates. Learning in the animals was induced through an appetitive conditioning model for odor and evaluated by chemotaxis assay. The hold periods employed in the project were: 0, 15, 30, 60, 120, 180, 210, 300 and 1440 minutes. Standardization of the learning model was performed by using custom plates with sticker to the chemotaxis assays and concentrated bacterial culture to feeding the nematodes. Results: The learning pattern characterized with E. coli HT115 in the project was found to be more chronic than that established in the reference with the OP50 strain. Data from assays performed with E. coli OP50-1 manifested high variability, however they seem to follow the trend predicted by the reference. To improve the counting of worms in the assays' pictures, a web application was developed for the semi-automation of the process. Conclusion: The diet offered to C. elegans, possibly, affects its learning and its formation of associative memories, due to the constitutive and metabolic differences between the microorganisms offered and their distinct strains.
Descrição
Citação
SILVA, Luiz Felipe Marquês da. Condicionamento positivo à butanona em C. elegans: Padronização do protocolo de aprendizagem associativa. São Paulo, 2022. 137 f. Trabalho de Conclusão de Curso (Graduação em Biomedicina) - Escola Paulista de Medicina (EPM), Universidade Federal de São Paulo (UNIFESP), São Paulo, 2022.