OBJ - Protein Synthesis

Question 1

Sketch the cloverleaf structure of a tRNA, and list the structural and functional features that are common to tRNAs.

Answer 1

3’ CCA tail = acceptor stem that AA binds to (7 base pairs)
D Arm/Loop = 4 base pairs
Anticodon Arm = 5 base pairs with Anticodon
T Arm/loop = 5 base pairs TΨC
Variable loop
5’ Terminal phosphate group

AA determined by Anticodon & variable loop

Question 2

Describe how amino acids are polymerized by the ribosome, including the factors and interactions that ensure the fidelity of the reaction.

Answer 2

5’ -> 3’ Amino Terminus to Carboxyl Terminus
1st AUG = beings coding Methionine
UAA = STOP codon

Question 3

Spliceosome

Answer 3

• Assembled by 5 snRNPS
• U1-U6
• Removes introns from transcribed pre-mRNA