Search results
Results from the WOW.Com Content Network
Bacterial transcription differs from eukaryotic transcription in several ways. In bacteria, transcription and translation can occur simultaneously in the cytoplasm of the cell, whereas in eukaryotes transcription occurs in the nucleus and translation occurs in the cytoplasm. [14]
Translation promotes transcription elongation and regulates transcription termination. Functional coupling between transcription and translation is caused by direct physical interactions between the ribosome and RNA polymerase ("expressome complex"), ribosome-dependent changes to nascent mRNA secondary structure which affect RNA polymerase activity (e.g. "attenuation"), and ribosome-dependent ...
Initiation of translation in bacteria involves the assembly of the components of the translation system, which are: the two ribosomal subunits (50S and 30S subunits); the mature mRNA to be translated; the tRNA charged with N-formylmethionine (the first amino acid in the nascent peptide); guanosine triphosphate (GTP) as a source of energy, and the three prokaryotic initiation factors IF1, IF2 ...
Initiation of translation is regulated by the accessibility of ribosomes to the Shine-Dalgarno sequence.This stretch of four to nine purine residues are located upstream the initiation codon and hybridize to a pyrimidine-rich sequence near the 3' end of the 16S RNA within the 30S bacterial ribosomal subunit. [1]
The transcription termination site is located after the ORF, beyond the translation stop codon. If transcription were to cease before the stop codon, an incomplete protein would be made during translation. [3] In eukaryotic genes with multiple exons, introns are removed and exons are then joined together after transcription to yield the final ...
This is part of the process that regulates the transcription of RNA to preserve gene expression integrity and are present in both eukaryotes and prokaryotes, although the process in bacteria is more widely understood. [1] The most extensively studied and detailed transcriptional termination factor is the Rho (ρ) protein of E. coli. [2]
Eukaryotic pre-mRNAs have their introns spliced out by spliceosomes made up of small nuclear ribonucleoproteins. [10] [11] In complex eukaryotic cells, one primary transcript is able to prepare large amounts of mature mRNAs due to alternative splicing. Alternative splicing is regulated so that each mature mRNA may encode a multiplicity of proteins.
An enhancer localized in a DNA region distant from the promoter of a gene can have a very large effect on gene transcription, with some genes undergoing up to 100-fold increased transcription due to an activated enhancer. [10] Enhancers are regions of the genome that are major gene-regulatory elements.