Protein Synthesis

Transcription

The process of synthesizing RNA from a DNA template.

Translation

The process of synthesizing a polypeptide chain from an mRNA template.

RNA polymerase

An enzyme that synthesizes RNA by linking RNA nucleotides complementary to a DNA template.

Codon

A sequence of three nucleotides on mRNA that codes for a specific amino acid.

mRNA

Messenger RNA; it carries genetic information from DNA to the ribosome.

tRNA

Transfer RNA; it brings the correct amino acid to the ribosome during translation.

rRNA

Ribosomal RNA; it makes up the ribosome and helps facilitate protein synthesis.

Exons

Coding regions of RNA that are expressed and joined together after introns are removed.

Introns

Non-coding regions of RNA that are removed during RNA processing.

5’ cap

A modified guanine nucleotide added to the 5’ end of mRNA for protection and ribosome attachment.

Poly-A tail

A sequence of adenine nucleotides added to the 3’ end of mRNA to prevent degradation.

Spliceosome

A complex of proteins and RNA that removes introns from pre-mRNA.

Frameshift mutation

A mutation caused by insertions or deletions that alters the reading frame of the genetic code.

Missense mutation

A mutation that changes one amino acid in a protein.

Nonsense mutation

A mutation that creates a stop codon, leading to a truncated protein.

Promoter

Region of DNA where RNA polymerase attaches to initiate transcription.

AUG

The start codon that begins the translation of mRNA into a polypeptide.

Ribosome

A cellular structure made of rRNA and proteins that synthesizes proteins by translating mRNA.

Polyribosome

A complex of multiple ribosomes translating the same mRNA strand simultaneously.

Central dogma

The flow of genetic information from DNA to RNA to protein.