1. DNA as the Blueprint:
- Gene expression begins with the DNA molecule, which contains the genetic instructions for making proteins.
- A specific segment of DNA, called a gene, holds the code for a single protein.
2. Transcription:From DNA to RNA:
- The first step in gene expression is transcription , where the DNA sequence of a gene is copied into a messenger RNA (mRNA) molecule.
- Cette molécule d'ARNm agit comme un messager, portant le code génétique de l'ADN dans le noyau aux ribosomes du cytoplasme.
3. Translation:From RNA to Protein:
- Translation is the process where the mRNA sequence is read by ribosomes, and amino acids are assembled in a specific order to create a protein.
- Transfer RNA (tRNA) molecules bring the correct amino acids to the ribosome, matching them to the codons on the mRNA.
4. Protein Folding and Function:
- After synthesis, the newly formed protein folds into a specific three-dimensional shape. This shape is essential for the protein's function.
en résumé:
* Gene expression starts with the DNA sequence of a gene.
* La transcription produit l'ARNm, transportant le code du gène aux ribosomes.
* Translation uses the mRNA code to assemble amino acids into a protein.
* The protein folds into its functional shape.
Par conséquent, la synthèse des protéines est le stade final de l'expression des gènes, où les informations génétiques codées dans l'ADN se traduisent en une protéine fonctionnelle. Ce processus est essentiel pour toutes les fonctions cellulaires, y compris la croissance, la réparation et le métabolisme.
