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

Una relazione contraria tra due geni è l'epistasi, in cui un gene maschera o altera l'espressione di un altro. Si dice che il gene che influenza sia epistatico al gene che viene mascherato.
Ad esempio, un gene che codifica per la proteina 1 correlata alla tirosinasi, o TYRP1, determina il colore del mantello dei cani: nero o marrone.
Un altro gene, Tyr, codifica per l'enzima tirosinasi, che è responsabile della pigmentazione negli animali. Una mutazione in questo gene può causare l'assenza di pigmento, risultando in un cane albino privo di qualsiasi colorazione.
L'ordine in cui questi due geni sono espressi può essere determinato da un test di epistasi.
Se una mutazione nel gene Tyr produce un cane albino che ha ancora il gene TYRP1 wild-type, si può concludere che il gene Tyr maschera l'effetto del gene TYRP1. Ciò significherebbe che Tyr è epistatico a TYRP1.

<ol>
	<li>Michels, CA (2002). Analisi dell'epistasi. In Tecniche genetiche per la ricerca biologica, C.A. Michels (a cura di). https://doi.org/10.1002/0470846623.ch6</li>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf e Richard E. Michod. "Danno genetico, mutazione ed evoluzione del sesso". Science 229, n. 4719 (1985): 1277-1281.</li>
</ol>

analisi dell'epistasi

Epistasis Analysis

Sebbene Mendel abbia scelto sette tratti non correlati nei piselli per studiare la segregazione genetica, la maggior parte dei tratti coinvolge molteplici interazioni genetiche che creano uno spettro di fenotipi. Quando l'interazione di vari geni o alleli in posizioni diverse influenza un fenotipo, si parla di epistasi. L'epistasi spesso comporta il mascheramento di un gene o l'interferenza con l'espressione di un altro (epistasi antagonista). L'epistasi si verifica spesso quando geni diversi fanno parte dello stesso percorso biochimico. L'espressione di un gene potrebbe dipendere da un prodotto genico nella stessa via biochimica.

Analisi epistatica

Lo studio delle interazioni epistatiche consente ai ricercatori di determinare la relazione funzionale tra i geni, l'ordinamento dei geni in un percorso e il modo in cui i diversi alleli incidono quantitativamente sui fenotipi. Consideriamo una reazione biochimica catalizzata da più proteine codificate da geni diversi. I geni coinvolti in tali reazioni biochimiche possono mascherare o inibire altri geni coinvolti nella stessa via biochimica, un fenomeno chiamato epistasi. Si dice che tali geni siano in un gruppo di epistasi. Analizzando la relazione epistatica tra diversi geni, gli scienziati possono costruire una mappa dell'ordine di funzione che mostra la sequenza di eventi e geni coinvolti in un percorso. Questo processo è chiamato analisi epistatica. Gli alleli selezionati per l'analisi epistatica devono avere fenotipi distinti.

Pertanto, da quando è stato introdotto il concetto di epistasi, è diventato sempre più chiaro che la maggior parte dei sistemi biologici coinvolge molti elementi genetici che interagiscono tra loro in modi molteplici e complessi.

Analisi dell'epistasi

Sebbene Mendel abbia scelto sette tratti non correlati nei piselli per studiare la segregazione genica, la maggior parte dei tratti coinvolge più interazioni geniche che creano uno spettro di ...

Education

Didattica

JoVE Core

Molecular Biology

Biologia Molecolare

Unit 2

Unità 2

Analyzing Gene Expression and Function

Analisi dell'espressione e della funzione genica

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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...

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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

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Gene Interaction Maps in Epistasis

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