Question

Define the different elements comprising a eukaryotic “gene body," whether or not copies of these different elements are present in mature mRNA, and whether or not they code for protein.

If you can include a photo with labels and include the terms transcriptional start site, 5' untranslated region (UTR), start codon, intron, exon, stop codon, and 3' untranslated region, that'd be great!!

Answer 1

Every Eukaryotic genes starts from a regulatory region, to which regulatory molecules which proteinaceous in nature bind and regulate DNA replication, transcription, RNA processing and translation.

DNA sequences called as enhancers bind to proteins called as activators or inducers to increase the rate of gene expression or transcription.

DNA sequences called as insulators or silencers bind to proteins called as repressors to decrease the rate of gene expression or transcription.

Coactivators work along with activators and Corepressors work along with repressors.

Another regulatory region is promoter to which RNA polymerase binds and initiate transcription.

Another regulatory region is terminator to which a terminator protein binds and stops transcription.

After regulatory region comes the transcription start site point This is the region from where transcription starts and transcription and at the transcription stop site.

After transcription, premature RNA is formed. This undergoes RNA processing to form a mature RNA. The processing involves capping, tailing and splicing of premature RNA. The premature RNA contained exams and introns. Exons are coding regions and introns are non coding regions. Both exons and introns constitutes a gene (gene is shown, but introns and exons are not show in the figure).

After RNA processing RNA undergoes translation to form a sequence of amino acids. But translation starts at start codon and stops at stop codon. Start codon is located after transcription start site and a stop codon is located before the transcription stop site. The region of translation from start codon to stop codon is called as open reading frame.

Between transcription start site and start codon and between transcription stop site and stop codon, untranslated regions are present. These regions undergo transcription but do not undergo translation.

I hope you understood everything. Please let me know in the comment section if you have any doubt. Please rate.