Molecular Basis of Inheritance Question 46
46. In the process of transcription in Eukaryotes, the RNA polymerase I transcribes - [2019, Odisa]
(a) Precursor of mRNA, hnRNA
(b) mRNA with additional processing, capping and tailing
(c) tRNA, 5 srRNA and snRNAs
(d) rRNAs $-28 S, 18 S$ and $5.8 S$
Show Answer
Answer : d
Hints & Solution
(d) During transcription in eukaryotes, RNA polymerase I transcribes $5.8 S, 18 S$ and $28 S$ rRNA. Eukaryotic transcription is carried out in the nucleus of the cell and proceeds in three sequential stages: initiation, elongation, and termination. Eukaryotes require transcription factors to first bind to the promoter region and then help recruit the appropriate polymerase. The state of chromatin structure at a specific region in eukaryotic DNA, along with the presence of specific transcription factors, works to regulate gene expression in eukaryotes. However, this complex interplay between proteins that serve as transcriptional activators or repressors and accessibility to the regulatory sequence is still just part of the story. Epigenetic mechanisms, including DNA methylation and imprinting, noncoding RNA, post-translational modifications, and other mechanisms, further enrich the cellular portfolio of gene expression control activities.
