GEN-3000 Lecture Notes - Lecture 12: Francis Crick, Start Codon, Transfer Rna
Document Summary
All cellular types of rna are transcribed from dna, while some viruses can copy rna from rna. Ribonucleotides contain the pyrimidine base uracil instead of thymine. Rna can be catalytic (ribozymes) -can carry out a job. If every nucleotide encoded a different amino acid-only 4 possibilities (augc) -questioning (how to get 20 amino acids) If every three4x4x4=64-crick and coworkers went on to formally prove. Used framshift mutations to show that they were correct-looked at insertions and deletions. They found if there was a single/two base shift then it changed everything but if there was a three then it maintained frame. Problem how do we know the sequence of input rna. Not possible at the time so make an rna with a single nucleotide. How do you figure out the herteomeric codons. The sequence was still not known for sure (could be aca, aac, or caa)
