Name: gene interaction maps in epistasis
Uploaded: 2023-04-30T10:14:33.000Z
Duration: 1 min 9 s
Channel: JoVE

Uma relação contrária entre dois genes é a epistasia, onde um gene mascara ou altera a expressão de outro. Diz-se que o gene influenciador é epistático ao gene que está sendo mascarado.
Por exemplo, um gene que codifica a proteína 1 relacionada à tirosinase, ou TYRP1, determina a cor da pelagem dos cães - preta ou marrom.
Outro gene, Tyr, codifica a enzima tirosinase, responsável pela pigmentação em animais. Uma mutação neste gene pode causar a ausência de pigmento, resultando em um cão albino que não possui coloração.
A ordem em que esses dois genes são expressos pode ser determinada por um teste de epistasia.
Se uma mutação no gene Tyr produz um cão albino que ainda possui o gene TYRP1 do tipo selvagem, pode-se concluir que o gene Tyr mascara o efeito do gene TYRP1. Isso significaria que Tyr é epistático para TYRP1.

<ol>
	<li>Michels, C.A. (2002). Análise de epistasia. Em Técnicas Genéticas para Pesquisa Biológica, C.A. Michels (Ed.). https://doi.org/10.1002/0470846623.ch6</li>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf e Richard E. Michod. "Dano genético, mutação e evolução do sexo." Ciência 229, nº 4719 (1985): 1277-1281.</li>
</ol>

análise de epistasia

Epistasis Analysis

Embora Mendel tenha escolhido sete características não relacionadas em ervilhas para estudar a segregação genética, a maioria das características envolve múltiplas interações genéticas que criam um espectro de fenótipos. Quando a interação de vários genes ou alelos em diferentes locais influencia um fenótipo, isso é chamado de epistasia. A epistasia geralmente envolve um gene que mascara ou interfere na expressão de outro (epistasia antagônica). A epistasia geralmente ocorre quando genes diferentes fazem parte da mesma via bioquímica. A expressão de um gene pode depender de um produto gênico na mesma via bioquímica. Análise epistática O estudo das interações epistáticas permite aos pesquisadores determinar a relação funcional entre os genes, a ordenação dos genes em uma via e como os diferentes alelos impactam quantitativamente os fenótipos. Considere uma reação bioquímica catalisada por múltiplas proteínas codificadas por genes diferentes. Os genes envolvidos em tais reações bioquímicas podem mascarar ou inibir outros genes envolvidos na mesma via bioquímica, um fenômeno denominado epistasia. Diz-se que tais genes estão em um grupo de epistasia. Ao analisar a relação epistática entre diferentes genes, os cientistas podem construir um mapa de ordem de função que mostra a sequência de eventos e genes envolvidos numa via. Este processo é chamado de análise epistática. Os alelos selecionados para a análise epistática devem possuir fenótipos distintos. Como tal, desde que o conceito de epistasia foi introduzido, tornou-se cada vez mais claro que a maioria dos sistemas biológicos envolve muitos elementos genéticos que interagem entre si de formas múltiplas e complexas.

Análise de Epistasia

Embora Mendel tenha escolhido sete características não relacionadas em ervilhas para estudar a segregação de genes, a maioria das características envolve múltiplas interações gênicas que criam um espectro de ...

Education

JoVE Core

Molecular Biology

Biologia Molecular

Unit 2

Unidade 2

Analyzing Gene Expression and Function

Analisando a Expressão e a Função Gênica

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

gene interaction maps in epistasis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene.

Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in the same pathway are considered part of one epistasis group.

Epistatic analysis uses these interactions to reveal how genes are related. Scientists can use it to identify the functional relationship between genes, determine the order of genes in a pathway, and see how different alleles affect phenotypes in a quantitative way. When multiple proteins encoded by different genes take part in a biochemical reaction, epistatic analysis can help build an order-of-function map that shows the sequence of events and the genes involved.

To compare genes in this way, the alleles chosen for analysis must have distinct phenotypes. Since epistasis was first described, it has become clear that many biological systems include genetic elements that interact in complex ways. These interactions help explain why many traits do not follow simple single-gene patterns.

Gene Interaction Maps in Epistasis

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epistasis analysis

Gene interaction maps in epistasis show how different genes work together to shape a phenotype. In epistasis, the interaction of genes or alleles at different locations affects the final trait. This often happens when one gene masks or interferes with the expression of another gene. Epistasis is common when genes are part of the same biochemical pathway. In that case, the expression of one gene can depend on a gene product made earlier in the pathway. Genes that mask or inhibit other genes in...

genome-wide association studies-gwas

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key terms and concepts

Explore how epistasis reveals gene interactions, pathway order, and phenotype changes through epistatic analysis in high school biology.

Gene Interaction Maps in Epistasis | JoVE K12

molecular biology

JoVE Core Biologia Molecular mostra os processos moleculares da célula através de vídeos de animação claros e concisos. Além disso, nos vídeos de Cientistas em ação, a aplicação desses conceitos é demonstrada por meio de experimentos reais em laboratórios modernos.

Gene Interaction Maps in Epistasis

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