Chapter 10 Flashcards
Each amino acid has:
3 bases + a codon in the mRNA
tRNAs align amino acids with corresponding codons on the _____ template
mRNA
The anticodon loop binds to the appropriate codon by
complementary base pairing.
Some tRNAs can recognize more than one mRNA codon, as a result of nonstandard base pairing (wobble) at the ____ codon position.
3rd
Name of bacterial ribosome
70S
Name of eukaryotic ribosome
80s
Ribosomes contain:
rRNA and proteins
rRNA is responsible for catalyzing
peptide bond formation
mRNAs have noncoding ______ at the ends.
UTRs
Most ______ mRNAs are mono-cistronic
eukaryote
Most ______ mRNAs are poly-cistronic
prokaryote
In both prokaryotes and eukaryotes, translation always starts with:
methionine (encoded by AUG)
Initiation codons in bacterial mRNAs are preceded by a __________ sequence, that aligns the mRNA on the ribosome.
Shine-Dalgarno
the first step of initiation: a specific initiator methionyl tRNA and the mRNA bind to the _____ ribosomal subunit.
small
A group of ribosomes bound to an mRNA molecule
polysome.
The initiator methionyl tRNA is bound to
eIF2
mRNA is brought to the complex by
eIF4E.
Ribosome scan down the mRNA to identify _____ initiation codon
AUG
When AUG is identified, _____ triggers the hydrolysis of GTP bound to eIF2.
eIF5
The initiator methionyl tRNA is bound at the ____ site. The next aminoacyl tRNA binds to the ____ site
P, A
stop codon examples
UAA, UAG, or UGA
________ recognize the signals and terminate protein synthesis.
Release factors
microRNAs are transcribed by:
RNA poly II
siRNAS are produced from ___________
double-stranded RNAs
proteins that facilitate folding of other proteins.
chaperones
Many chaperones were initially identified as
heat-shock proteins
folding takes place here
chaperonin
catalyzes disulfide bond formation
PDI
catalyzes isomerization of peptide bonds that involve proline residues.
Peptidyl prolyl isomerase
cleavage of the polypeptide chain removes portions such as the initiator methionine from the amino terminus.
proteolysis
transfer phosphate groups from ATP to the hydroxyl groups of side chains of serine, threonine, or tyrosine.
protein kinases
Phosphorylation is reversed by
protein phosphatases
cAMP-dependent protein kinase has:
two regulatory and two catalytic subunits.
attached to the amino group of the side chain of a lysine residue, then more are added to form a chain.
Ubiquitin
a large protease complex
proteasome.
