Question

The overall process of prokaryotic and eukaryotic gene expression are very similar, employing the same basic mechanisms of transcription initiation, elongation, and termination by RNA polymerase followed by translation of the mRNA by ribosomes and charges tRNAs. The eukaryotic process, however, has a few unique aspects to I. List or describe some of these important differences.

Answer 1

Prokaryotic Gene Expression	Eukaryotic Gene Expression
Polycystronic mRNA(one mRNA codes for more than one protein)	Monocistronic mRNA(one mRNA codes for single protein)
Single RNA polymerase synthesize all RNA species	RNA polymerase I- rRNA RNA polymerase II-mRNA RNA polymerase III- tRNA
Promoter is cis acting and contains consensus sequences recognized by sigma factor.	Different promoters and transcription factors are present for different RNA polymerases.
Protein synthesis is initiated by binding of 70 S ribosome to the shine Dalgarno sequence.	Protein synthesis is initiated by recognition of 5' cap and kozak sequence.
N-formylmethionine is the first amino acid in newly synthesized polypeptide.	Methionine is the first amino acid in newly synthesized polypeptide.
Translation initiation factors: IF -1, IF-2,IF-3 Elongation Factors:EF-Tu,EF-Ts,EF-G Termination:RF-1,RF-2,RF-3	Translation initiation and Elongation factors: eIF 2, eIF1, eIF1A, eIF3 and eIF5
Transcription and translation occurs parallely.	After transcription mRNA undergoes post transcriptional modifications for eg. Splicing, polyadenylation and cleavage, capping at 5' end.
Coding sequences are continuous	coding sequences are interrupted by non coding/intergenic sequences known as introns