Gene Expression and the Central Dogma of Molecular Biology
The "Central Dogma" describes the two-step process, transcription and translation, by which the information in genes flows into proteins.
Transcription: DNA to RNA
In the nucleus, an enzyme called RNA polymerase reads the DNA sequence and creates a complementary strand of Messenger RNA (mRNA). Before leaving the nucleus, this pre-mRNA undergoes splicing, where non-coding sequences (introns) are removed, leaving only the coding sequences (exons).
Translation: RNA to Protein
The mRNA travels to the ribosome, the cell’s protein factory. Here, Transfer RNA (tRNA) molecules match specific amino acids to the codons (three-base sequences) on the mRNA. This creates a polypeptide chain that eventually folds into a functional protein.
1 vue