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

العلاقة المعاكسة بين جينين هي الرعاف ، حيث يخفي أحد الجينات أو يغير تعبير الآخر. يقال إن الجين المؤثر معرفي للجين الذي يتم إخفاؤه.
على سبيل المثال، يحدد الجين الذي يرمز للبروتين 1 المرتبط بالتيروزيناز أو TYRP1 لون معطف — أسود أو بني.
جين آخر ، Tyr ، يرمز لإنزيم التيروزيناز ، المسؤول عن التصبغ في. يمكن أن تتسبب الطفرة في هذا الجين في غياب الصبغة ، مما يؤدي إلى ألبينو يفتقر إلى أي تلوين.
يمكن تحديد الترتيب الذي يتم به التعبير عن هذين الجيلين عن طريق اختبار رعاف.
إذا أنتجت طفرة في جين Tyr ألبينو لا يزال يحتوي على جين TYRP1 من النوع البري ، فيمكن استنتاج أن جين Tyr يخفي تأثير جين TYRP1. هذا يعني أن Tyr هو معرفي ل TYRP1.

<ol>
	<li>ميشيلز ، سي إيه (2002). تحليل Epistasis. في التقنيات الوراثية للبحوث البيولوجية ، C.A. ميشيلز (محرر). https://doi.org/10.1002/0470846623.ch6</li>
	<li>برنشتاين ، هاريس ، هنري سي بيرلي ، فريدريك أ. هوبف ، وريتشارد إي ميشود. "الضرر الجيني والطفرة وتطور الجنس". علم 229 ، رقم 4719 (1985): 1277-1281.</li>
</ol>

تحليل الحجب الجيني

Epistasis Analysis

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على الرغم من أن مندل اختار سبع سمات غير مرتبطة في البازلاء لدراسة الفصل الجيني، إلا أن معظم السمات تنطوي على تفاعلات جينية متعددة تخلق طيفًا من الأنماط الظاهرية. عندما يؤثر تفاعل الجينات أو الأليلات المختلفة في مواقع مختلفة على النمط الظاهري، فإن هذا يسمى epistasis. غالبًا ما تشتمل الحجب الجيني على إخفاء جين واحد أو التدخل في التعبير عن جين آخر (الحجب الجيني العدائي). يحدث الرعاف غالبًا عندما تكون الجينات المختلفة جزءًا من نفس المسار الكيميائي الحيوي. قد يعتمد التعبير عن الجين على منتج جيني في نفس المسار الكيميائي الحيوي.

التحليل المعرفي

تسمح دراسة التفاعلات المعرفية للباحثين بتحديد العلاقة الوظيفية بين الجينات، وترتيب الجينات في المسار، وكيف تؤثر الأليلات المختلفة كميًا على الأنماط الظاهرية. فكر في تفاعل كيميائي حيوي يتم تحفيزه بواسطة بروتينات متعددة مشفرة بواسطة جينات مختلفة. يمكن للجينات المشاركة في مثل هذه التفاعلات الكيميائية الحيوية أن تخفي أو تمنع الجينات الأخرى المشاركة في نفس المسار الكيميائي الحيوي، وهي ظاهرة تسمى epistasis. ويقال إن مثل هذه الجينات موجودة في مجموعة epistasis واحدة. من خلال تحليل العلاقة المعرفية بين الجينات المختلفة، يمكن للعلماء بناء خريطة ترتيب الوظائف التي توضح تسلسل الأحداث والجينات المشاركة في المسار. وتسمى هذه العملية التحليل المعرفي. يجب أن يكون للأليلات المختارة للتحليل المعرفي أنماط ظاهرية مميزة.

على هذا النحو، منذ طرح مفهوم الحجب الجيني، أصبح من الواضح بشكل متزايد أن معظم الأنظمة البيولوجية تتضمن العديد من العناصر الجينية التي تتفاعل مع بعضها البعض بطرق متعددة ومعقدة.
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على الرغم من أن مندل اختار سبع سمات غير مرتبطة في البازلاء لدراسة الفصل الجيني ، إلا أن معظم السمات تتضمن تفاعلات جينية متعددة تخلق طيفا من ...

Education

JoVE Core

Molecular Biology

البيولوجيا الجزيئية

Unit 2

الوحدة الثانية

Analyzing Gene Expression and Function

تحليل التعبير الجيني ووظيفته

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

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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Using SNP Patterns to Link Disease Risk

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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 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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