[Lec 10+11] Key Terms: Translation

Question 1

virus

Answer 1

an infectious agent that replicates only in living cells of other organisms; only contains genetic information, infectious proteins (coat/envelopes), viral specific proteins

Question 2

reverse transcriptase

Answer 2

encoded in retroviral genome-synthesizes DNA from RNA

Question 3

hydrophobic stacking

Answer 3

keeps bases in place and prevents unconventional hydrogen bond formation with mRNA; more flexibility to move-last in stack

Question 4

open reading frame

Answer 4

protein coding region that is framed by a start and stop codon within the reading frame

Question 5

reading frame

Answer 5

the grid in which we read the triplet codons

Question 6

initiator RNA

Answer 6

small subunit decoding center-reads mRNA

Question 7

Svedberg units

Answer 7

measure of how fast a particle sediments

Question 8

E site

Answer 8

exit site; tRNA exits the ribosome

Question 9

P site

Answer 9

peptide site; tRNA holds the growing polypeptide

Question 10

A site

Answer 10

aminoacyl site; aminoacyl tRNA binds

Question 11

Shine-Delgarno sequence

Answer 11

16S rRNA of 30S subunit is complementary; where translation starts for prokaryotes; AUG is positioned in P site, if 30S to Shine-Delgarno sequence (AGGAGGU)

Question 12

Kozak sequence

Answer 12

when the 40S subunit recognizes the 5’ cap of the mRNA, it then scans for the AUG within this sequence; where translation begins for eukaryotes

Question 13

consensus sequence

Answer 13

resides the most abundant in each position of the sequence

Question 14

promoter consensus sequence

Answer 14

important for prokaryotic transcription (alpha factor binding site)

Question 15

IF3

Answer 15

prokaryotes; prevents 30S and 50S from associating; only 30S subunit can bind to RNA; blocks the E site

Question 16

IF1

Answer 16

prokaryotes; blocks A site

Question 17

IF2

Answer 17

prokaryotes; a GTPase and binds to the initiator tRNA; positions initiator tRNA onto P site; 1 GTP is hydrolyzed

Question 18

eIF3

Answer 18

eukaryotes; goes to P site; prevents dissocation of 40S and 60S; blocks E site

Question 19

eIF1

Answer 19

goes and blocks A site

Question 20

eIF4

Answer 20

binds to 5’ cap of mRNA

Question 21

eIF4 and Poly A binding proteins

Answer 21

hold eukaryotic mRNA into a circular shape to go round and round to allow ribosome to be more efficient

Question 22

Class 1 Release Factors

Answer 22

RF1 and RF2; recognize stop codons; shaped like tRNA

Question 23

Class 2 Release Factors

Answer 23

RF3; hydrolyzes GTP: conformational change-release Class 1 RFs, allows dissociation

Question 24

signal sequence

Answer 24

bound by SRP (signal recognition particle) which binds to the SRP receptor on the ER

Question 25

importin

Answer 25

binds at their nuclear localization sequence and transports into the nucleus