BIO 325 Lecture Notes - Lecture 1: Proflavine, Phosphodiester Bond, Reading Frame
Document Summary
A gene"s nucleotide sequence is co-linear with the amino acid sequence. Yanofsky how do mutations in dna correspond to mutations in protein. Gene expression: mutagenized e. coli, grew on media that contains tryptophan, replica plated to find colonies that don"t grow without tryptophan, mapped sites of mutations in dna by recombination, purified mutant trpa proteins and determined amino acid sequences. Wild-type phenotype may result when the reading frame is restored through frameshift mutations, which are insertions or deletions that shift the reading frame. Transcription: new phosphodiester bond forms at the 3" end (like in dna replication, rna is also made in 5" 3" direction. Translation: mrna is read in 5" 3" direction. Only one dna strand is transcribed for a gene, but either top or bottom strand is used to transcribe different genes: rna-like strand = sense strand = coding strand, template strand = antisense strand = noncoding strand. In vitro translation with synthetic mrnas reveal the first codon identities.
