tRNA

Question 1

tRNA

Answer 1

Adapter RNA/ transfer RNA

Question 2

Role?

Answer 2

1. Translation
2. Primer during Reverse Transcription of Retrovirus

Question 3

Size

Answer 3

75 - 95 ntds.

Mostly 76 ntds

Question 4

Present in

Answer 4

1. Cytosol
2. Semi-autonomous Organelle

Question 5

First Sequenced

Answer 5

Yeast tRNA^ala

Question 5

2D / Secondary structure

Answer 5

clover leaf like

Well defined stems and loops

Question 6

Acceptor arm

Answer 6

1. 7 BP
2. 4 unpaired ntds.
   (includes CCA in all tRNA)

Question 7

Anticodon Arm

Answer 7

1. 5-6 BP
2. Loop having Anticodons

Question 8

TΨC

Answer 8

1. Ψ is Pseudouridylation
2. 5 BP
3. contains modified Bases- Pseudouridine

Question 9

D-arm

Answer 9

1. 3-4 BP
2. D is Dihydrouridine
3. Contains modified Bases- Dihydrouridine

Question 9

Variable Loop

Answer 9

1. 4-5 ntds. actually
2. 10-24 max

Question 10

Modified bases are mainly present in_____

Answer 10

Loop

Question 11

Due to modification, they won’t be able to base pairing within?

Answer 11

within tRNA

Question 12

Shape of Tertiary Structure?

Answer 12

L-shape

Question 13

1st extended helix

Answer 13

Acceptor arm + TΨC

Question 14

2nd extended helix

Answer 14

Anticodon loop + D-arm

Question 15

_____ bond formed b/w bases

Answer 15

Hydrogen

Question 16

Unusual Bases in _____?

Answer 16

Primary structure

Question 17

Examples of Unusual Bases?

Answer 17

1. Pseudouridine
2. Dihydrouridine
3. Hypoxanthine/Inosine
4. Thymine
5. Methyl Guanine

Question 18

Unusual bases (conc. in the loop) disrupt the ____

Answer 18

Formation of Hydrogen bond

Question 19

Potential recognition sites for various proteins are present in

Answer 19

in the region of Conc. Unusual bases

Question 20

Modified bases are essential for tRNA.

true or False?

Answer 20

False

Question 21

Cells lacking these unusual bases show___

Answer 21

reduced rates of growth

Question 22

These unusual bases lead to___

Answer 22

Improved tRNA Function