Question

During which step of the replication-translation process does each RNA first play a role?

Answer 1

During replication process, the two strands of DNA are separated and complementary strand are synthesized for each original strand. DNA polymerase enzyme synthesizes the new strand. To initiate the replication process, a few nucleotides length RNA primer binds to DNA strand and DNA polymerase adds the nucleotides in the growing strand. Except in this initiation step, in no other stage RNA is involved DNA replication.

After the replication process is completed, the necessary proteins in a cell are synthesized by transcription and translation processes. During transcription, one of the DNA strand acts as a template and mRNA is synthesized by RNA polymerase enzyme. Once, the transcription is completed, mRNA undergo processing by 5` capping, poly adenylation tail and removal of noncoding sequences by splicing mechanism. In all these stages, mRNA is involved.

Once the transcription process is finished, the rRNA joins the two ribosomal subunits and initiates the protein synthesis process (translation). The tRNA adds amino acids complementary to the mRNA sequence and involved in the synthesis of polypeptide chain. In this process, all the 3 RNAs - mRNA, rRNA and tRNA are involved.