Part 1: The Genetic Code

Polycistronic

prokaryotic mRNA is with many ORFs

Monocistronic

eukaryotic mRNA is with one ORF

5’ cap and poly a tail

eukaryotic mRNA (mature) has…

No tail

prokaryotic mRNA has ____

3

every sequence has at least __ reading frames which mutations can shift

tRNAs

crick hypothesized “adaptors” which are actually ____ read the genetic code

anticodon

trinucleotide region on the bottom of tRNA that base pairs with complementary mRNA

cell free translation

used to decipher to crack the genetic code

Marshall neinberg and Heinrich Matthaei

added polyU to a cell free translation extract containing labeled amino acids and recovered polyPhe

Triplet filter binding assay

used to decipher the genetic code, found 54 of the 64 codons, use radioactive tRNAs and bind to ribosomes with synthetic RNA triplets, wash unbound,

Mg2+

at high non physiological concentrations of _ the ribsomone does not need AUG to start translation … helped us to test larger substrates and identify the remaining codons of the genetic code

Degeneracy

the genetic code is which is dictated by what is present at the first position in the anticodon

Wobble

the _ hypothesis accounts for the degeneracy of the genetic code

32

a minimum of ___ tRNAs are needed to translate the 61 codons

20

how many amino acids are possible for the 61 codons