How is prokaryotic gene regulation different from eukaryotic gene regulation?
it's for my Biology PAP review. Thank You! :)
- chromozorzLv 58 years agoFavourite answer
Well there are a few major differences and a few minor. I am a big fan of why questions in science. It's a good idea to ask why there would be any differences at all!? It's a well known secret; start simple then add the layers! So I'll get the jist of it across and then give a list of differences I can think of.
So - what is actually different between pro and eukaryotes which would cause their genome to be controlled differently? The most obvious thing to me is that eukaryotes tend to be multicellular, prokaryotes are single celled. Could this simple observation tell us why? (not surprisingly, it does!). Every cell in our bodies contains the same genetic information (since every cell is descended from a single cell) - Yet if I look at the difference between a neurone and a skin cell, they are completely different in terms of morphology (how they look) and biochemistry (how they work behave). And we know that these different cellular traits are largely controlled by genetic information. So we are faced with a kind of paradox; if every cell in our bodies are controlled by genetic information and they all contain the same genetic information, then how can all our different cells do their specific jobs?
Gene regulation of course!
Complex regulatory networks - Genetic elements/sequences (enhancers/silencers/insulators) which can be kilobases from the gene they regulate - chromatin organisation - histone methylation/acetylation - Complex protein:protein:DNA interaction during polymerase recruitment - huge array of TF's in eukaryotic genomes - Genes contain multiple introns so splicing occurs - mRNAs contain 5'cap and poly-A tails - mRNAs contain 5' and 3' UTRs - Extensive post transcriptional regulation eg miRNA regulation - translational regulation of genes
minor/basic mechanisms of regulation - sequences which regulate a gene in very close proximity to the gene in question - genes and associated regulatory elements can be found as an OPERON (wiki operon and learn the lac operon) - little/no post transcriptional regulation - simple transcriptional complexes - simpler polymerase - no 5'cap or polyA - no chromatin organisation - mostly cis regulation - no nucleus so genome is always exposed to any proteins in the cell -
(n.b. I have only given a few examples, there are waaaay more. I have kept it simple as well so learn specific examples for your exam (lac operon; number of subunits compared to eu / prokaryotic RNA polymerase; sigma factors; how the extracellular environment affects the genome eg. hormones, or cell signalling - which is how a cell reacts to certain signals in it's environment; alternative splicing; RNA interference; histone methylation)Source(s): Good luck. I'm a final year genetics student.
- vogesLv 44 years ago
Chubb and Mooney are half of proper and half fallacious. Your bet is very good. Part of the rationale has to do with structure - genes make proteins and there are numerous more locations to place proteins in eukaryotic cells than in prokaryotes. Yet another cause has to do with the multicellular eukaryotes, which have unique tissues and organs - each and every distinctive tissue and organ requires one of a kind proteins, all from the equal DNA, which requires more than one phases of legislation. The multicellular organism undergoes progress as good, requiring distinct proteins at specific occasions (fetus vs newborn vs adult, for example), The prokaryote must stay easy, since the prokaryote has fast environmental changes that require rapid response (the 'bloodless splash' of reality for fecal coliforms, as one in all my professors used to assert). I am sure there are other causes, I simply can't think of them now, anyone else?