Protein Synthesis Flashcards
A Site
The first site in a ribosome, to which a tRNA molecule can first bind/enter the ribosome.
Anticodon
The series of three nitrogen bases found on a tRNA molecule, complementary to the matching codon on mRNA.
Base Substitution
A type of mutation in which one nitrogen base is mistaken for another.
Chaperone Protein
A protein that assists in protein folding by helping the polypeptide fold up.
Codon
A series of three successive nitrogen bases that codes for one amino acid.
Elongation
In Transcription: the second stage, in which RNA polymerase travels down DNA and brings in complementary mRNA nucleotides to match each DNA nucleotide. In Translation: the second stage, in which tRNA molecules enter the ribosome until a stop codon is reached on mRNA, to lengthen the polypeptide formed.
E Site
The third and final site of a ribosome, from which a tRNA molecule exits and leaves, leaving behind its amino acid to the polypeptide formed.
Exon
A coding region of mRNA’s primary transcript.
Frameshift Mutation
A type of mutation in which there is an insertion or deletion of a nitrogen base in a genetic information sequence going from DNA to mRNA. Shifts the entire reading frame, changing the polypeptide formed.
Guanine Cap
The series of guanine bases added to the front of mRNA during RNA Processing to protect it from enzyme damage in the cytoplasm and aid in attachment to a ribosome.
Initiation
In Transcription: the first stage, in which RNA polymerase binds to the promoter on DNA with the aid of transcription factors. In Translation: the first stage, in which the ribosome travels along mRNA until it finds the start codon, AUG, and binds to the mRNA to begin elongation.
Intron
A non-coding region of mRNA’s primary transcript.
Mature mRNA
The final transcript version of mRNA that is ready for translation; has undergone RNA Processing/splicing.
mRNA
Messenger RNA, the RNA that is created as a copy of the genetic information in DNA during transcription during protein synthesis.
Mutagens
Chemical agents that can cause mutations.
Mutations
Mistakes or unintentional changes to genetic information sequences.
P Site
The second (middle) site of a ribosome, into which a tRNA molecule shifts from the A site.
Poly-A Tail
A long series of adenine bases that is added to the end of mRNA during RNA Processing to protect it from enzyme damage in the cytoplasm and regulate how long it stays in the cytoplasm making proteins.
Primary Transcript
The “rough draft” of mRNA that is created in transcription.
Promoter Site
An area along DNA to which RNA polymerase binds during transcription.
Reading Frame
The proper way of reading a strand of mRNA.
Release Factor
A molecule that enters the ribosome during termination of translation to end the polypeptide formed.
RNA Polymerase
The enzyme that is used to create mRNA during transcription.
Splicing
RNA Processing; the process during which the primary transcript of mRNA is edited to make it ready for translation.
Start Codon (AUG)
The codon in mRNA that signals when translation should begin.
Stop Codon (UAA, UGA, UAG)
One of three codons in mRNA that signals when translation should end.
Signal Sequence
A series of amino acids that indicates to a ribosome to attach to the rough ER to allow a protein to be exported out of the cell.
Terminator
An area on the DNA that signals when RNA Polymerase should stop carrying out transcription.
Termination Sequence
The sequence of nitrogen bases that indicates when transcription should end.
Transcription
The first stage of protein synthesis, during which mRNA is created in the nucleus as a copy of the genetic information stored in DNA.
Transcription (Initiation) Factors
Chemicals that aid in the attachment of RNA polymerase to DNA during the initiation phase of transcription.
Translation
The second and final stage of protein synthesis, during which the mRNA created during transcription is used to synthesize a protein in the cytoplasm, using a ribosome.
tRNA
Transfer RNA; RNA that brings amino acids to translation to create the polypeptide needed.
tRNA Charging
The process of adding an amino acid onto a tRNA molecule to “recharge” it, or allow it to bring amino acids to translation again.
