Question

The central dogma of protein synthesis in kinetoplastid is

• A. G-RNA $\to$ DNA $\to$ mRNA $\to$ protein
• B. DNA $\to$ G-RNA $\to$ mRNA$\to$ protein
• C. DNA $\to$ DNA $\to$ mRNA $\to$ protein
• D. mRNA $\to$ G-RNA $\to$ DNA $\to$ protein

Answer 1

Answer: (B)

DNA $\to$ G-RNA $\to$ mRNA$\to$ protein

• The mitochondrial DNA of the kinetoplastids has many open reading frames (ORF's) (sequences from which RNA- is synthesized which is later translated to protein by protein synthesis ).
• These ORF's unlike the ORF's of the regular nuclear genes are incomplete. So, though they can be transcribed to form an mRNA (specifically pre-edited mRNA) for it to be translated to a protein more modifications to the mRNA are needed (editing of mRNA).
• These modifications are brought about by the use of another RNA molecule called the Guide RNA (G-RNA).
• Once the editing is done mature mRNA is then finally translated to protein.
  Thus, the correct option is B