PROTEIN SYNTHESIS TRANSCRIPTION TRANSLATION PROTEIN SYNTHESIS DNA RNA

PROTEIN SYNTHESIS: TRANSCRIPTION & TRANSLATION

PROTEIN SYNTHESIS: DNA -> RNA -> Protein

Transfer RNA (t. RNA) picks up amino acid in cytoplasm and carries them to the ribosome t. RNA has ANTIMessenger RNACODONS (m. RNA) carries nucleotide sequence from nucleus to ribosome m. RNA has CODONS TYPES OF RNA Ribosomal RNA (r. RNA) - found in ribosome - associates with proteins to form ribosomes in the cytoplasm

T-RNA AND M-RNA CODONS (in m. RNA) and ANTI-CODONS (in t. RNA) work together to make protein during TRANSLATION Remember: proteins are also called polypeptides! t. RNA

TRANSCRIPTION: DNA produces RNA - Occurs in the nucleus - Genetic code is transferred to m. RNA

A segment of DNA separates: one segment serves as a pattern for RNA • RNA Polymerase adds nucleotides to the template DNA strand. • (Remember: no “T” in RNA, only “U”, A-U, G-C)

• A genetic code for a protein in DNA is copied into the m. RNA • A genetic code is made of “CODONs” in m. RNA • Each codon is made of 3 nitrogen bases • Each codon codes for an AMINO ACID

TRANSLATION: • PROTEIN SYNTHESIS! • Occurs in ribosomes in cytoplasm or RER

Steps of Translation: 1. The m. RNA leaves the nucleus and enters the cytoplasm 2. Ribosomes attach to the m. RNA 3. t. RNA picks up free amino acids in the cell and carries them to the ribosome 4. The anti-codon in t. RNA matches the codon in m. RNA and start adding amino acids to a growing protein The bonds between amino acids are peptide bonds!! Translation animation

TRANSLATION OF GENETIC CODE IN MESSENGER RNA INTO PROTEINS INSTRUCTIONAL VIDEO

YOU CAN FIND THE AMINO ACID SEQUENCE OF A PROTEIN USING THE CODONS IN M-RNA AND A CODON TABLE! Example: DNA sequence: AAT m. RNA sequence: UUA CGC ATC GCG UAG CODONS: UUA = Leucine amino acid GCG= Alanine UAG = Stop amino acid AMINO ACID/PROTEIN SEQUENCE: LEU- ALA – STOP **THERE ARE ONLY 20 AMINO ACIDS, BUT MILLION S OF PROTEINS: IT’S THE COMBINATION OF THOSE AMINO ACIDS THAT WILL GENERATE MILLIONS OF PROTEINS!**

CODON WHEEL