From gene to protein DNA mRNA protein trait nucleus cytoplasm aa From gene to protein nucleus cytoplasm transcription translation DNA mRNA protein ribosome trait

from nucleic acid language to amino acid language Translation from nucleic acid language to amino acid language

How does mRNA code for proteins? TACGCACATTTACGTACGCGG DNA 4 ATCG AUGCGUGUAAAUGCAUGCGCC mRNA 4 AUCG ? Met Arg Val Asn Ala Cys Ala protein 20 How can you code for 20 amino acids with only 4 nucleotide bases (A,U,G,C)?

mRNA codes for proteins in triplets TACGCACATTTACGTACGCGG DNA codon AUGCGUGUAAAUGCAUGCGCC mRNA AUGCGUGUAAAUGCAUGCGCC mRNA ? Met Arg Val Asn Ala Cys Ala protein

The code Code for ALL life! Code is redundant Start codon Stop codons strongest support for a common origin for all life Code is redundant several codons for each amino acid 3rd base “wobble” Why is the wobble good? Start codon AUG methionine Stop codons UGA, UAA, UAG

How are the codons matched to amino acids? 3 5 DNA TACGCACATTTACGTACGCGG 5 3 mRNA AUGCGUGUAAAUGCAUGCGCC codon 3 5 UAC Met GCA Arg tRNA CAU Val anti-codon amino acid

From gene to protein DNA mRNA protein trait nucleus cytoplasm aa From gene to protein nucleus cytoplasm transcription translation DNA mRNA protein ribosome trait

Building a polypeptide 1 2 3 Building a polypeptide Initiation brings together mRNA, ribosome subunits, initiator tRNA Elongation adding amino acids based on codon sequence Termination end codon Leu Val release factor Ser Met Met Met Met Leu Leu Leu Ala Trp tRNA C A G U A C U A C G A C A C G A C A 5' U 5' U A C G A C 5' A A A U G C U G U A U G C U G A U A U G C U G A A U 5' A A U mRNA A U G C U G 3' 3' 3' 3' A C C U G G U A A E P A 3'

Can you tell the story? RNA polymerase DNA amino acids exon intron tRNA pre-mRNA 5' GTP cap mature mRNA aminoacyl tRNA synthetase poly-A tail 3' large ribosomal subunit polypeptide 5' tRNA small ribosomal subunit E P A ribosome