Lecture on Protein Synthesis by Amoeba Sisters

Introduction

• Importance of understanding how DNA results in traits (e.g., eye color)
• DNA contains genetic information coding for proteins that create pigments
• Process of converting DNA to protein: Protein Synthesis

Importance of Proteins

• Proteins play various roles: transport, structure, enzymes, protection, etc.
• Essential for living organisms
• Protein synthesis is a constant process in cells

DNA and Protein Synthesis

• DNA located in the nucleus of cells
• Some DNA is noncoding or inactive
• Focus on genes coding for active proteins

Role of RNA

• RNA: nucleic acid similar to DNA with distinct roles
• Key role in protein synthesis
• Two major steps: Transcription and Translation

Transcription

• Occurs in the nucleus
• DNA is transcribed into a message
• Enzyme: RNA polymerase connects complementary RNA bases to the DNA
• Result: single-stranded mRNA (messenger RNA)
• mRNA editing is crucial for accurate protein synthesis

Translation

• Occurs in the cytoplasm
• mRNA attaches to ribosomes (made of rRNA)
• Ribosome builds protein by reading mRNA codons
• tRNA (transfer RNA) carries amino acids, the building blocks of proteins
• tRNA matches amino acids to mRNA codons through complementary anticodons

Process of Translation

• Ribosome reads mRNA in triplets called codons
• Example: mRNA codon AUG matches with tRNA anticodon UAC carrying methionine
• Codon chart helps determine which amino acid corresponds to each mRNA codon
• Multiple codons can code for the same amino acid (e.g., leucine)
• Amino acids linked by peptide bonds to form a protein
• Stop codons signal the end of protein synthesis

Conclusion

• DNA directs protein synthesis with help from mRNA, rRNA, and tRNA
• Protein may undergo folding, modification, and transportation based on its function
• Encouragement to stay curious and explore further topics