Gene Regulation And Protein Synthesis Flashcards
What do RNA polymerases do?
Bind to promoters to initiate transcription
What are RNA polymerases?
Multi subunit complexes which make up RNA
What is TFIID?
General transcription factor
Role of TATA box binding protein in transcription:
Introduces kink to DNA to determine start and direction of transcription
Provides landing platforms for transcription factors and RNA polymerase
What is elongation in transcription?
Addition of nucleotides to RNA chain in 5’-3’ direction
Termination in translation:
Site encounters stop codon
Termination protein binds to codon
Ribosome dissociates
Causes change in transferase
tRNA releases protein
What is initiation in translation?
Formation of initiation complex
Energy provided by GTP
Requires additional general transcription factors
Role of rRNA
Combines with proteins to form ribosomes
Role of tRNA
Carries amino acids to be incorporated into proteins
Role of mRNA
Carries genetic information for protein synthesis
What are the 3 types of RNA polymerases in eukaryotes?
Pol I
Pol II
Pol III
Termination in transcription:
Release of finished RNA
Role of Aminoacyl-tRNA synthetases
Catalyses covalent attachment of amino acids to their corresponding tRNA molecule
What is elongation in translation?
Anticodons of tRNA form base pairs with codons on mRNA
Role of Peptidyl transferase
Catalyses peptide bond formation between amino acids in P and A sites
Role of EF-2
moves ribosomes along mRNA
Post translational modifications (4):
Glycosylation
Disulphide bonds (ER)
Folding/assembly of multi-subunit proteins (ER)
Specific proteolytic cleavage (ER, Golgi)
What are the 3 tRNA binding sites?
P (peptidyl site)
A (acceptor site)
E (exit site)
What do free ribosomes in cytoskeleton produce?
Proteins for cytosol, nucleus, and mitochondria
What do bound ribosomes on rough ER produce?
Proteins for plasma membrane, ER, Golgi
Point mutation
Change in single base
