Name: rna types in gene expression
Uploaded: 2025-05-22T09:05:54.000Z
Duration: 1 min 20 s
Channel: JoVE

K12 Standards

Georgia Standards of Excellence

9-12

Biology

SB2.a

Types of RNA

Istnieją trzy typy RNA, które odgrywają bezpośrednią rolę w syntezie białek - informacyjny RNA lub mRNA, transferowy RNA lub tRNA oraz rybosomalny RNA lub rRNA.
mRNA jest najpierw transkrybowane z DNA przez komplementarne parowanie zasad. W cząsteczce mRNA kodony, grupy trzech nukleotydów, określają sekwencję aminokwasów i wskazują, gdzie powinna rozpocząć się i zakończyć synteza białek.
Translacja następuje po przemieszczeniu się mRNA do cytoplazmy, gdzie jest umieszczane na małej podjednostce rybosomalnej za pomocą jej rRNA.
Następnie cząsteczka tRNA, z sekwencją antykodonu składającą się z trzech nukleotydów na jednym końcu i specyficznym aminokwasem na drugim, wiąże się z komplementarnym kodonem w mRNA.
Prawidłowe tRNA wiążą się sekwencyjnie z mRNA, a rRNA w dużej podjednostce rybosomalnej katalizuje tworzenie wiązania peptydowego między dwoma aminokwasami.
Rybosom przemieszcza się w dół mRNA, tworząc polipeptyd z sekwencją aminokwasów określoną przez mRNA.

rodzaje rna

W syntezie białek biorą udział trzy główne typy RNA: informacyjny RNA (mRNA), transferowy RNA (tRNA) i rybosomalny RNA (rRNA). Te RNA pełnią różnorodne funkcje i można je ogólnie sklasyfikować jako RNA kodujące i niekodujące. Niekodujące RNA odgrywają ważną rolę w regulacji ekspresji genów w odpowiedzi na zmiany rozwojowe i środowiskowe. Niekodującymi RNA u prokariotów można manipulować w celu opracowania skuteczniejszych leków przeciwbakteryjnych do stosowania u ludzi i zwierząt. RNA pełni różnorodne, ale współpracujące funkcje Główny dogmat biologii molekularnej głosi, że DNA zawiera informację kodującą białka, a RNA wykorzystuje te informacje do kierowania syntezą białek. Informacyjny RNA (mRNA) to RNA kodujący białko. Składa się z kodonów – sekwencji trzech nukleotydów kodujących konkretny aminokwas. Transferowy RNA (tRNA) i rybosomalny RNA (rRNA) to niekodujące RNA. tRNA działa jak cząsteczka adaptorowa, która odczytuje sekwencję mRNA i umieszcza aminokwasy we właściwej kolejności w rosnącym łańcuchu polipeptydowym. rRNA i inne białka tworzą rybosom – miejsce syntezy białek w komórce. Podczas translacji rybosomy poruszają się wzdłuż nici mRNA, gdzie stabilizują wiązanie cząsteczek tRNA i katalizują tworzenie wiązań peptydowych pomiędzy aminokwasami. Zatem różne typy RNA pełnią specyficzne, ale uzupełniające się funkcje podczas syntezy białek. Niekodujące RNA u eukariotów regulują ekspresję genów Niekodujące RNA inne niż tRNA i rRNA były początkowo uważane za „śmieci genomowe”, ponieważ nie kodowały białek. Jednakże ich rolę w regulacji ekspresji genów odkryto w ciągu ostatnich kilku dziesięcioleci i nadal są one szeroko badane. Na podstawie ich długości, niekodujące RNA można sklasyfikować jako małe regulatorowe RNA (< 100 nukleotydów) lub długie niekodujące RNA (> 200 nukleotydów). Zarówno małe regulatorowe RNA, jak i długie niekodujące RNA regulują ekspresję genów poprzez zmianę różnych etapów transkrypcji i translacji. Niekodujące RNA wpływają na splicing mRNA - usuwanie niekodujących segmentów i łączenie sekwencji kodujących białka. W ten sposób kontrolują tworzenie różnych wariantów białka z jednego genu. Małe regulatorowe RNA, takie jak mikroRNA (miRNA) i małe interferujące RNA (siRNA), wiążą się z komplementarnymi sekwencjami mRNA i hamują syntezę białek poprzez blokowanie dostępu mechanizmów translacyjnych do mRNA lub przez degradację samego mRNA. Długie niekodujące RNA oddziałują i rekrutują enzymy, które chemicznie modyfikują DNA i histony – białka pomagające pakować DNA w jądro – w celu aktywacji lub tłumienia transkrypcji.

Rodzaje RNA

W syntezie białek biorą udział trzy główne typy RNA: informacyjny RNA (mRNA), transferowy RNA (tRNA) i rybosomalny RNA (rRNA). Te RNA pełnią różnorodne ...

Education

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Anatomy and Physiology

Anatomia i fizjologia

Unit 1

Jednostka 1

Essential Cellular Processes

Podstawowe procesy komórkowe

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

rna types in gene expression

RNA types play different roles in gene expression. RNA, or ribonucleic acid, helps carry and use genetic information in cells. The main types discussed here are messenger RNA, ribosomal RNA, and transfer RNA.

Messenger RNA, or mRNA, carries the genetic code from DNA to the ribosome. The ribosome is the site where proteins are made. Ribosomal RNA, or rRNA, is a key part of the ribosome itself. Transfer RNA, or tRNA, brings the correct amino acids to the ribosome during protein building.

These RNA molecules work together during protein synthesis. mRNA provides the message, rRNA helps form the protein-making machinery, and tRNA matches amino acids to the code. Understanding these RNA types helps explain how cells turn genetic instructions into proteins.

RNA Types in Gene Expression

the central dogma

Central Dogma: DNA to Protein

The central dogma explains how genetic information flows in cells from DNA to RNA to protein. It is a core idea in molecular biology and helps show how genes influence cell function. DNA stores the instructions. During transcription, a cell copies a gene into RNA, which is a related nucleic acid. That RNA message can then be used in translation to build a protein. Proteins carry out many jobs in cells and help determine traits. The central dogma links the genetic code in DNA to the molecules...

replication in eukaryotes

Eukaryotic DNA Copying at the Replication Fork

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types of rna

RNA types play different roles in gene expression. RNA, or ribonucleic acid, helps carry and use genetic information in cells. The main types discussed here are messenger RNA, ribosomal RNA, and transfer RNA. Messenger RNA, or mRNA, carries the genetic code from DNA to the ribosome. The ribosome is the site where proteins are made. Ribosomal RNA, or rRNA, is a key part of the ribosome itself. Transfer RNA, or tRNA, brings the correct amino acids to the ribosome during protein building. These...

transcription

Transcription and RNA Synthesis

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translation

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regulation of expression at multiple steps

regulation-of-expression-at-multiple-steps

How Cells Control Gene Expression

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what is the cell cycle?

Cell Cycle Stages in Cell Growth

The cell cycle is the process that controls cell growth and division. It explains how one cell makes two new cells. This process helps cells grow and reproduce.

interphase

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the cell cycle control system

Cell Cycle Checkpoints and Cyclin Control

The cell cycle is controlled by checkpoints that help a cell move from one phase to the next and begin mitosis. This control system uses internal regulatory molecules and outside signals to send stop or advance instructions. It makes sure each step is finished before the cell moves forward. Cyclins and cyclin-dependent kinases, or Cdks, are the main regulators of the cell cycle. They act during the G1, G2, and M phases. These regulators work at specific checkpoints to keep cell division...

molecular factors affecting cell division

molecular-factors-affecting-cell-division

Cell Cycle Regulators That Control Division

Cell division is controlled by outside signals and by internal cell cycle regulators. Nearby cell death can encourage division, and human growth hormone (hGH) can also promote it. In contrast, too little hGH or crowded cells can slow or stop division. Inside the cell, regulator molecules help each stage finish correctly before the next stage begins. Some regulators act directly on the cycle, while others affect the activity or production of other regulatory proteins. These molecules can either...

what is meiosis?

Meiosis and the Formation of Gametes

Meiosis is the cell division process that forms gametes, or sex cells. It reduces the chromosome number so offspring can inherit the correct amount of genetic material. This process includes two successive divisions. First, one cell divides, and then the resulting cells divide again. These steps separate the genetic material in a controlled way. Meiosis helps explain how sexual reproduction passes traits from one generation to the next. It is a key topic in high school biology because it...

overview of cell signaling

Cell Signaling Pathways and Responses

Cell signaling pathways and responses help cells communicate and react to changes. Cells send signals to one another, and those signals can trigger a specific response in the target cell. A signal usually begins when a signaling molecule reaches a cell with the right receptor, which is a protein that receives the message. The receptor helps the cell recognize the signal and start the communication process. Inside the cell, the message can move through a signaling pathway. This pathway passes...

types of signaling molecules

Chemical Messengers in Cell Signaling

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g protein-coupled receptors

G Protein-coupled Receptor Signaling

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cellular differentiation

From Stem Cell to Specialized Cells

Cellular differentiation turns unspecialized cells into specialized cells with specific jobs. This process helps a complex organism, such as a human, develop from a single fertilized egg into a body with many cell types. Nerve cells, muscle cells, and epithelial cells are examples of the final cell types that appear during development. A zygote is the first cell after fertilization. It is a totipotent stem cell, which means it has very high differentiation potential and can form all cell types...

key terms and concepts

Explore messenger RNA, ribosomal RNA, and transfer RNA, and see how each RNA type helps carry and use genetic information during protein synthesis.

RNA Types in Gene Expression | JoVE K12

anatomy and physiology

JoVE Core Anatomy and Physiology showcases the anatomical and physiological details of the human body in comprehensive, clear, and engaging video animations. This collection of lessons focuses on the structures, components, functions, and requirements of the human body. It is complemented by scientist-in-action videos that demonstrate the application of this knowledge in real-world medical and research settings.

The Central Dogma

Replication in Eukaryotes

Transcription

Translation

Regulation of Expression at Multiple Steps

The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. ...

Construct an explanation of how the structures of DNA and RNA lead to the expression of information within the cell via the processes of replication, transcription, and translation

What is Meiosis?

Meiosis I

Meiosis is the division of a diploid cell into haploid cells forming sperm and eggs in animals through differentiation. Meiosis I is the first stage of ...

Meiosis II

Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for ...

Crossing over

Nondisjunction

Genome Copying Errors

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Overview of DNA Repair

In order to be passed through generations, genomic DNA must be undamaged and error-free. However, every day, DNA in a cell undergoes several thousand to a ...

Base Excision Repair

One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and ...

RNA Editing

RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or ...

Mutations

Teratogenicity

The ability of a drug to produce structural deformations and functional abnormalities in the developing embryo or the fetus is called teratogenicity, and ...

Mechanisms of Retrovirus-induced Cancers

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Construct an argument based on evidence to support the claim that inheritable genetic variations may result from:New genetic combinations through meiosis (crossing over, nondisjunction), Non-lethal errors occurring during replication (insertions, deletions, substitutions), Heritable mutations caused by environmental factors (radiation, chemicals, and viruses)

SB2.b

Transgenic Plants

Recombinant DNA technology called transgenesis is often used to add a foreign gene or remove a detrimental gene from an organism. Such genetically ...

Transgenic Organisms

Overview

Transgenic organisms are genetically engineered to carry transgenes&#x2014;genes from a different species&#x2014;as part of their genome. The ...

Testing For Genetically Modified Foods

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University
Genetic modification of foods has been a controversial issue due to debated ...

Genetic Engineering of Model Organisms

Transgenesis, or the use of genetic engineering to alter gene expression, is widely used in the field of developmental biology. Scientists use a number of ...

Ask questions to gather and communicate information about the use and ethical considerations of biotechnology in forensics, medicine, and agriculture

SB2.c

Obtain, evaluate, and communicate information to analyze how genetic information is expressed in cells

RNA Types in Gene Expression

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