Transcription and Translation

Gene

a segment of DNA containing genetic information
needed for making a specific protein or RNA molecule

Transcription

production of RNA to DNA

Translation

production of protein from RNA

central dogma of biology

genetic information flows from DNA to RNA to protein

mRNA

carries genetic info coding for production of proteins

rRNA

structural component of ribosomes

tRNA

an intermediary between mRNA sequences that amino acids use to build proteins

RNA Polymerase

uses template directed synthesis to form a new RNA strand

promoter

helps RNA polymerase find sites of transcription

termination sequences

DNA sequences that when transcribed to RNA make a structure that halts transcription, forming a hairpin loop

Components of a fully processed mRNA

5’ 7 methylguanosine cap, 3’ poly A tail, removal of introns

exons

expressed, contain genetic information that becomes protein

introns

not expressed, intervening sequences (filler)

3 sites of mRNA

exit, peptidyl, amino

ribosome

enzyme that translates proteins

anti-codon region

3 nucleotides that interact with specific codons

Amino acid attachment site

at the 3’ end of the 3’ end

stages of protein synthesis

initiation, elongation, termination

initiation

the process of the cell finding the right starting point on the mRNA

Elongation

the middle stage where the actual building of the molecule occurs and RNA polymerase moves along the template strand

Termination

the ribosome hits a stop code and breaks down the entire “machine” so that the process can occur again

missense mutation

changes the identity of the amino acid

nonsense mutation

result in the presence of an early stop codon

silent mutation

no effect on the sequence

frame shift

insertion or deletion of a nucleotide