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

Przeciwstawnym związkiem między dwoma genami jest epistaza, w której jeden gen maskuje lub zmienia ekspresję drugiego. Mówi się, że gen wpływający jest epistatyczny w stosunku do genu, który jest maskowany.
Na przykład gen kodujący białko 1 związane z tyrozynazą lub TYRP1 określa kolor sierści psów - lub brązowy.
Inny gen, Tyr, koduje enzym tyrozynazę, który jest odpowiedzialny za pigmentację u zwierząt. Mutacja w tym genie może powodować brak pigmentu, co powoduje, że pies albinos nie ma żadnego ubarwienia.
Kolejność, w jakiej te dwa geny są wyrażane, można określić za pomocą testu epistazy.
Jeśli mutacja w genie Tyr wytworzy psa albinosa, który nadal ma gen TYRP1 typu dzikiego, można wywnioskować, że gen Tyr maskuje działanie genu TYRP1. Oznaczałoby to, że Tyr jest epistatyczny w stosunku do TYRP1.

<ol>
	<li>Michels, C.A. (2002). Analiza epistazy. W: Techniki genetyczne w badaniach biologicznych, C.A. Michels (red.). https://doi.org/10.1002/0470846623.ch6</li>
	<li>Bernstein, Harris, Henry C. Byerly, Frederic A. Hopf i Richard E. Michod. "Uszkodzenia genetyczne, mutacje i ewolucja płci". Science 229, nr 4719 (1985): 1277-1281.</li>
</ol>

analiza epistazy

Epistasis Analysis

Chociaż Mendel wybrał siedem niepowiązanych ze sobą cech grochu do badania segregacji genów, większość cech obejmuje wiele interakcji genów, które tworzą spektrum fenotypów. Kiedy interakcja różnych genów lub alleli w różnych lokalizacjach wpływa na fenotyp, nazywa się to epistazą. Epistaza często wiąże się z maskowaniem jednego genu lub zakłócaniem ekspresji innego (epistaza antagonistyczna). Epistaza często występuje, gdy różne geny są częścią tego samego szlaku biochemicznego. Ekspresja genu może zależeć od produktu genu na tym samym szlaku biochemicznym. Analiza epistatyczna Badanie interakcji epistatycznych pozwala naukowcom określić związek funkcjonalny między genami, kolejnością genów w szlaku oraz ilościowy wpływ różnych alleli na fenotypy. Rozważmy reakcję biochemiczną katalizowaną przez wiele białek kodowanych przez różne geny. Geny biorące udział w takich reakcjach biochemicznych mogą maskować lub hamować inne geny zaangażowane w ten sam szlak biochemiczny, zjawisko zwane epistazą. Mówi się, że takie geny należą do jednej grupy epistazy. Analizując epistatyczną relację między różnymi genami, naukowcy mogą skonstruować mapę porządku funkcji, która pokazuje sekwencję zdarzeń i genów zaangażowanych w dany szlak. Proces ten nazywany jest analizą epistatyczną. Allele wybrane do analizy epistatycznej muszą mieć różne fenotypy. W związku z tym od czasu wprowadzenia koncepcji epistazy staje się coraz bardziej jasne, że większość systemów biologicznych obejmuje wiele elementów genetycznych, które oddziałują ze sobą na wiele i złożonych sposobów.

Analiza epistazy

Chociaż Mendel wybrał siedem niepowiązanych cech grochu do badania segregacji genów, większość cech obejmuje wiele interakcji genów, które tworzą spektrum ...

Education

JoVE Core

Molecular Biology

Biologia molekularna

Unit 2

Jednostka 2

Analyzing Gene Expression and Function

Analiza ekspresji i funkcji genów

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

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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JoVE Core Molecular Biology showcases the molecular processes of the cell through clear and concise animated video lessons. Additionally, in scientist-in-action videos, these concepts' application is demonstrated through real experiments in modern laboratories.

Gene Interaction Maps in Epistasis

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