Biochem RNA Processing & Translation (3)

  1. 5'-7 Methyl Cap
    • The cap synthesized during transcription that protects the mRNA from degradation and is required for translation.
    • (Hint: It is placed on the 5' end)
  2. Aminoacyl-tRNA Synthetase
    A group of amino acid -specific enzymes that joins amino acids to tRNAs.
  3. Anticodon
    A sequence of three bases of a tRNA molecule that pairs with the complementary three-nucleotide codon of an mRNA molecule during protein synthesis.
  4. Branch Point
    A crucial Adenine residue located near the polypyrimidine tract on the intron. It's 2'-OH attacks the phosphodiester bond to initiate intron cleavage.
  5. Codon
    A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid.
  6. Degeneracy
    • There are only 20 amino acids, therefore there are multiple codons for most of the amino acids.
    • (Name the phenomenon)
  7. Endonuclease
    Nuclease that hydrolyzes a phosphodiester bond WITHIN a nucleic acid molecule.
  8. Exonuclease
    Nuclease that hydrolyzes a phosphodiester bond at the END of a nucleic acid molecule.
  9. Genetic Code
    The set of ALL possible three-base codons. (64 total)
  10. Initiation Factor
    Proteins that bind to the small subunit of the ribosome during the initiation of translation.
  11. Intron
    • Non-coding protein sequences that must be removed from mRNA before translation.
    • (Hint: aka "intervening sequences")
  12. Exon
    The bits of protein coding sequences separated by introns on mRNA.
  13. Pre-mRNA
    RNA that is transcribed as an exact copy of the DNA, prior to intron removal (splicing).
  14. 'P' Site
    The ribosomal binding site that holds the tRNA carrying the growing POLYPEPTIDE chain.
  15. 'A' Site
    The ribosomal binding site that holds the tRNA carrying the next AMINO ACID to be added to the polypeptide chain.
  16. Poly(A) Binding Protein (PAB)
    A specific protein that binds to the Poly(A) tail and to eIF4F to stabilize the 5' complex
  17. Peptidyl Transferase
    Enzyme responsible for peptide bond formation in the ribosome during translation.
  18. Poly(A) Tail
    The 200-250 adenine sequence added to form the 3' end of the pre-mRNA that protects it from degradation and is required for translation.
  19. Polypyrimidine Tract
    A pyrimidine-rich region located prior to the AG at the 3' end of the intron that is composed of C's and U's.
  20. Precursor
    Large transcripts from which the RNA molecules are cleaved.
  21. Mature Products
    The final RNA molecules resulting from the cleavage of the precursor during RNA processing.
  22. Reading Frame
    • The division of a sequence of DNA or RNA into a particular series of three-nucleotide codons.
    • (Hint: Three of these are possible for any particular sequence.)
  23. Ribosome
    A large macromolecular complex that carries out protein synthesis; consisting of two subunits.
  24. Large Subunit
    The ribosomal subunit responsible for catalyzing formation of the peptide bond. (50S/60S)
  25. Small Subunit
    The ribosomal subunit responsible for stabilizing codon-anticodon interaction. (30S/40S)
  26. Shine-Delgarno Sequence
    The consensus sequence located next to the correct AUG start codon in bacteria.
  27. Splicing
    The process of intron removal.
  28. Small Nuclear RNA
    Types of RNA contained in the spliceosome that base pairs with the 5' exon-intron junction and the segment surrounding the branch point. (U1 and U2, respectively)
  29. Spliceosome
    A huge complex containing proteins and snRNAs that catalyzes the splicing reactions by bringing the branch point and intron-exon junctions together and promoting transesterification.
  30. Start Codon
    The first AUG in the mRNA that marks the beginning of translation.
  31. Stop Codon
    Either UGA, UAG, or UAA that marks the end of translation
  32. Transesterification
    • A reaction that involves the breaking of one phosphodiester bond and the formation of one phosphodiester bond.
    • (Hint: Splicing occurs by TWO of these reactions.)
  33. "Wobble" Base
    The variable third nucleotide in a codon.
Card Set
Biochem RNA Processing & Translation (3)
Biochem RNA Processing & Translation