Name: central dogma: dna to protein
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

The Central Dogma

O dogma central da biologia molecular afirma que a informação codificada no DNA é transferida para o RNA, que então direciona a síntese de proteínas com base nessas instruções.
Primeiro, durante a transcrição, o DNA é usado como modelo para sintetizar RNA mensageiro ou mRNA.
O mRNA representa uma cópia da fita codificante do DNA, exceto que as timinas são substituídas por uracilas.
Em seguida, o mRNA é traduzido em uma cadeia de aminoácidos por um ribossomo.
Aqui, grupos de três nucleotídeos no mRNA, também conhecidos como códons, ligam-se a sequências complementares ou anticódons nas moléculas de RNA ou tRNA de transferência.
Cada tRNA está ligado a um aminoácido específico, dependendo do códon específico.
Por exemplo, o códon CCA se liga a um tRNA ligado à prolina, enquanto o AGC se liga a um tRNA ligado à serina.
Desta forma, o código genético especifica a ordem dos aminoácidos no polipeptídeo resultante, que é posteriormente processado para se tornar uma proteína funcional.

o dogma central

O dogma central explica o fluxo de informação genética dos nucleotídeos do DNA para a sequência de aminoácidos das proteínas. RNA é o elo perdido entre DNA e proteínas No início dos anos 1900, os cientistas descobriram que o DNA armazena todas as informações necessárias para as funções celulares, e que as proteínas desempenham a maior parte dessas funções. No entanto, os mecanismos de conversão da informação genética em proteínas funcionais permaneceram desconhecidos durante muitos anos. Inicialmente, acreditava-se que um único gene era convertido diretamente em sua proteína codificada. Duas descobertas cruciais em células eucarióticas desafiaram esta teoria. Primeiro, a produção de proteínas não ocorre no núcleo. Em segundo lugar, o DNA não está presente fora do núcleo. Essas descobertas desencadearam a busca por uma molécula intermediária que conecte o DNA à produção de proteínas. Descobriu-se que esta molécula intermediária era RNA. O RNA é sintetizado no núcleo usando o DNA como modelo. O RNA recém-sintetizado é semelhante em sequência à fita de DNA, exceto que a timina é substituída por uracila. Em eucariotos, esse transcrito primário é posteriormente processado, removendo as regiões não codificantes da proteína, tampando a extremidade 5' e adicionando uma cauda poli-A 3', para criar O mRNA maduro, que é então exportado para o citoplasma. O código genético é redundante As proteínas são criadas a partir de 20 aminoácidos em eucariotos. A combinação de quatro nucleotídeos em conjuntos de três fornece 64 (43) códons possíveis. Isso significa que mais de um códon pode codificar um aminoácido individual. Assim, diz-se que o código genético é redundante, ou degenerado. Frequentemente, mas nem sempre, os códons que especificam os mesmos aminoácidos diferem apenas no terceiro nucleotídeo do trio. Por exemplo, os códons GUU, GUC, GUA e GUG representam todos o aminoácido valina. No entanto, AUG é o único códon que representa o aminoácido metionina. O códon AUG também é o códon onde começa a síntese proteica e é, portanto, chamado de códon de início. A redundância no sistema minimiza os efeitos nocivos das mutações. Por exemplo, uma alteração na terceira posição do códon pode não alterar necessariamente o aminoácido codificado, não causando assim nenhuma alteração na funcionalidade da proteína. O código genético é universal Com algumas exceções, a maioria dos organismos procarióticos e eucarióticos usam o mesmo código genético para a síntese de proteínas. Esta universalidade do código genético permitiu avanços nas pesquisas científicas na área da agricultura e da medicina. Por exemplo, a insulina humana pode agora ser fabricada em larga escala em bactérias utilizando tecnologia de DNA recombinante. A tecnologia de DNA recombinante envolve o uso de material genético de diferentes espécies. Os genes que codificam a insulina humana são unidos ao DNA bacteriano e inseridos em uma célula bacteriana. A célula bacteriana então realiza a transcrição e tradução para produzir a proteína insulina humana, que pode tratar o diabetes em pacientes.

O Dogma Central

O dogma central explica o fluxo de informações genéticas dos nucleotídeos do DNA para a sequência de aminoácidos das proteínas.
O RNA é o elo perdido entre ...

Education

JoVE Core

Anatomy and Physiology

Anatomia e Fisiologia

Unit 1

Unidade 1

Essential Cellular Processes

Processos Celulares Essenciais

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

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 that do most of the work in living systems.

Central Dogma: DNA to Protein

the central dogma

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...

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types of rna

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transcription

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translation

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molecular factors affecting cell division

molecular-factors-affecting-cell-division

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what is meiosis?

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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...

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g protein-coupled receptors

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cellular differentiation

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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 the central dogma and how genetic information moves from DNA to RNA to protein. Learn how transcription and translation connect genes to proteins.

Central Dogma: DNA to Protein | JoVE K12

anatomy and physiology

O JoVE Core Anatomia e Fisiologia apresenta detalhes anatômicos e fisiológicos do corpo humano em animações  abrangentes, claras e envolventes. Esta coleção de vídeos se concentra nas estruturas, componentes, funções e requisitos do corpo humano. É complementada por vídeos de cientistas em ação que demonstram a aplicação desse conhecimento em instalações médicas e de pesquisa do mundo real.

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Types of RNA

Transcription

Translation

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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

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SB2.c

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

Central Dogma: DNA to Protein

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