This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Processed Unprocessed Has promoter Lacks promoter Has poly A tail, Has no introns Lacks poly A tail, Retains introns Could be located anywhere in genome Located near original copy Origin: mRNA reverse transcripted to DNA, reinserted Origin: duplication of gene Nonfunctional because lacks promoter Nonfunctional because of mutation Gene Regulation-most DNA is not genes; 5-10% genes are transcribed at a time But why are so many genes turned off?? Dependent upon:-Developmental Stage some genes are only needed for certain stages-Tissue Differentiation different tissues require different genes-Environmental Conditions some genes only needed for certain environmental conditions-cells need to turn off unneeded genes to conserve energy and resources How are genes regulated ?: Steps where genes can be regulated 1.Transcription – does transcription happen or not? 2. RNA processing/RNA stability – does this occur or not? If not processed gene isn’t made; RNA Stability ex: snip the tails off mRNA, and protein won’t be encoded 3.Translation – does it occur or not? Ex: piece of dsRNA conjugated to 5’ untranslated region of RNA and blocks translation Note: dsRNA resemble viruses, and cells tend to target these, so the mRNA ends up being destroyed as collateral damage 4.Post-translation – ex: phosphorylation [on/off switch for gene regulating] Where is most regulation? Transcription because less resources are wastedWhere is most regulation?...
View Full Document