Passing Genetic Notes in Class CC106 / Discussion D by John R. Finnerty

BioUNITY

BacteriaEukaryotaArchaea LUCA Last Universal Common Ancestor metabolism protein assembly genetic material genetic code Unity & Diversity

Metabolic Unity Use the same enzymes to digest sugars.

Molecular Unity Use the same molecular machinery to build proteins.

Genetic Unity Use DNA & RNA to transmit encoded information. & use the same genetic code.

LEUCINE ISO- LEUCINE CYST EINE DNA alphabet Portion of a gene RNA alphabet Protein sequence c -C-T-A-T-T-A-A-G-T- -C-U-A-U-U-A-A-G-U- gene is transcribed into a “message” message is translated into a protein using the genetic code -G-A-T-A-A-T-T-C-A- string of amino acids LIC

Human insulin gene E. coli bacterium Human insulin protein Implication of Shared Genetic Code

Key Properties of the Code Each codon (= word) is 3-letters long. There is a reading frame. The code is redundant: multiple words say the same thing. The code is somewhat robust to errors. Not all mutations (= spelling mistakes) change the meaning.

I. Using the 1-letter abbreviations for amino acids, compose a note instructing your teammates to perform some action. 20 available letters: A C D E F G H I K L M N P Q R S T V W Y

II. Reverse translate your protein note into DNA letters (ACGT) using the genetic code. C T A G A A G C C A A T

II. Reverse translate your protein note into DNA letters (ACGT) using the genetic code. C T A G A A G C C A A T IIa. Add 0, 1, or 2 dummy letters at the beginning and end to hide the reading frame. C GA

III. Transmit note, now encoded in DNA form to another team, who will mutate 1 of every 5 letters. IIIa. Pass mutated message to intended recipients. C G C T A G A A G C C A A T A C G T T A G A G G C C A A A A

IV. Recipients translate message (after being told the correct reading frame). C G T T A G A G G C C A A A A R STOP RPK

IV. Recipients translate message (after being told the correct reading frame). C G T T A G A G G C C A A A A R STOP RPK C G T T A G A G G C C A A A A LE A K

V. Deduce what the message is supposed to say. C G T T A G A G G C C A A A A LE A K Clues: should direct me to perform an action. Message would be mutated in 3 places. But, not all DNA mutations would change the meaning of the message (the amino acid).

V. Deduce what the message is supposed to say. C G T T A G A G G C C A A A A LE A K PE E K Clues: should direct me to perform an action. Message would be mutated in 3 places. But, not all DNA mutations would change the meaning of the message (the amino acid).

V. Deduce what the message is supposed to say. C G T T A G A G G C C A A A A LE A K C G C C A G A G G A AA A A A PE E K Clues: should direct me to perform an action. Message would be mutated in 3 places. But, not all DNA mutations would change the meaning of the message (the amino acid).

V. Deduce what the message is supposed to say. C G T T A G A G G C C A A A A LE A K LE A P Clues: should direct me to perform an action. Message would be mutated in 3 places. But, not all DNA mutations would change the meaning of the message (the amino acid).

V. Deduce what the message is supposed to say. C G T T A G A G G C C A A A A LE A K C G T T A G A G G C C C C A A LE A P Clues: should direct me to perform an action. Message would be mutated in 3 places. But, not all DNA mutations would change the meaning of the message (the amino acid).

V. Deduce what the message is supposed to say. C G T T A G A G G C C A A A A LE A K C G T T A G A G G C C A A T A LE A N Clues: should direct me to perform an action. Message would be mutated in 3 places. But, not all DNA mutations would change the meaning of the message (the amino acid).

T C A G T TTT TTC TTA TTG FFLLFFLL TCT TCC TCA TCG SSSSSSSS TATT ACT AAT AG YY**YY** TGT TGC TGA TGG CC*WCC*W TCAGTCAG C CTT CTC CTA CTG LLLLLLLL CCT CCC CCA CC G PPPPPPPP CAT CAC CAA CAG HHQQ HHQQ CGT CG CC GAC GG RRRRRRRR TCAGTCAG A ATT ATC ATA ATG II I M ACT ACC ACA ACG TTTTTTTT AAT AAC AAA AAG NNKK NNKK AGT AGC AGA AG G SSRRSSRR TCAGTCAG G GTT GTC GTA GTG VVVVVVVV GCT GC CG CAG CG AAAAAAAA GAT GAC GAA GAG DDEE DDEE GGT GG CG GA GG G GGGGGGGG TCAGTCAG Third letter in codon Second letter in codon First letter in codon