Question

Two of the steps involved in producing nematode resistant tobacco plants based on the process of RNAi are mentioned below. Write the missing steps in its proper sequence.
(a).........., (b)using Agrobacterium as vector introduce it into tobacco., (c) ......... , (d).......... (e)initiates-RNA interference, (f).......... (g)......... , (h) ..........

Answer 1

A nematode Meloidegyne incognitia infects the roots of tobacco plants which reduce the production of tobacco. The infection can be prevented using RNA interference (RNAi) process which is checked by silencing of specific mRNA due to a complementary ds RNA. The ds RNA binds and prevents translation of the mRNA. By using Agrobacterium vectors, nematode-specific genes were introduced into the host plants which produce both sense and antisense RNA in the host cells. These two RNAs are complementary to each other and form a double stranded RNA (ds RNA) that initiates RNAi and hence, silences the specific mRNA of the nematode. The parasite cannot survive in transgenic host and so, prevents the plants from pests.

Thus the correct order is

1. ds RNA binds and prevents translation of the mRNA.
   
2. using Agrobacterium as vector introduce it into tobacco
   
3. this produce both sense and antisense RNA in the host cells.
   
4. These two RNAs are complementary to each other and form a double stranded RNA
   
5. initiates-RNA interference
   
6. it silences the specific mRNA of the nematode
   
7. The parasite cannot survive in transgenic host
   
8. so the plant is prevented from pest