Protein Synthesis

Describe the process of transcription: unwinding, complimentary base pairing, separating

  • At the transcription process, DNA is unwound first. Then, RNA polymerase makes the pair between a single stranded DNA and nucleotides to produce mRNA. With the transcribed information, mRNA falls off from the DNA strand.

(unwound)

How did today’s activity do a good job of modelling the process of transcription? In what ways was our model inaccurate?

  • I could understand in detail how the complementary pairing is made when I wrote down the mRNA code on the mRNA strand by passing the DNA through DNA helicase. However, I forgot the unwinding step of DNA which was inaccurate compared to the real synthesis.

 

Describe the process of translation: initiation, elongation, and termination

 

  • In the translation process, there is an initiation step which a ribosomal subunit and initiator tRNA with the anticodon UAC is attached to the start codon on mRNA, AUG at P site. Then, at the elongation step, other tRNA amino acids bind with the ribosome at A site. As next tRNA amino acid comes into the A site, the previous one is shifted to the P site, and tRNA without amino acid is released to the out of the ribosome. At the final step, termination, the ribosomal subunit meets the stop codon on the mRNA and a bound release factor dissociate the ribosomal subunit.

 

 

How did today’s activity do a good job of modelling the process of translation? In what ways was our model inaccurate?

  • Finding a start codon and stop codon was helpful to understand when/why a ribosomal subunit is attached and detached from a mRNA. However, based on my knowledge, there can be maximum three sites in the ribosomal subunit, so the form having only two sites is not always accurate.