DNA and RNA Replication (+Transcription and Translation)

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you forget the polyadenylation (addition of adenine nucleotides at the 3' of the RNA transcript) that ends the termination process and after that, the RNA splicing (intron/exon).

>>8393898
Ah, yea, thank you.
The Polyadenyl is just that long strand of A's at the end to keep the RNA from degrading iirc.

I apologize for the lame question as well, but what exactly are Introns?
Are they just unneeded pieces of code, and are therefore spliced out, or is it something else?

>>8393953
they are unneeded, or they contain skipped exons, or they serve as a mutation pool, or they have regulatory sequences/secondary structures. it all depends.

>>8393953
>The Polyadenyl is just that long strand of A's at the end to keep the RNA from degrading iirc.
it's got like tons or protein sticking to it and also some weird loops that do some regulation or even anchoring iirc.

>>8393978
Ah, alright.
Whatever the fuck your genes decide I guess.

>>8393986
Yeah, I heard that somewhere too.
That bit's a little confusing isn't it?
Perhaps the looping adds enzymes to speed up the transcription, if there's protein stuck to the A cap?

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>>8393953
They have a LOT of roles, some of them still being researched.

When in the genome, they can act as transcription regulators (sequences that start or stop transcription and the like). When they're being transcribed, they can act as time switches, as in, delaying transcription so that the protein expression coincides with another pathway product. If you remove those introns, yous shorten the sequence and the product comes earlier, causing problems in metabolic pathways and whatever function they used to serve. Introns during transcription can also be used in alternative splicing, wherein they are kept during transcription and they are translated along with the exons to yield a slightly different protein that could serve a different purpose, increasing the repertoire of proteins available without taking up more space (separate large DNA sequences). There are other functions as well, after translation, in combination with Exon junction complex, look it up if you're interested.

I attached a pic from a review paper on the role of introns that I used two years ago in an essay that outlines the role of introns, those that we know of.

>>8394009
Yeah, I'd heard about Alternative Splicing before, but not the other things you've mentioned.
From what you've read, it sounds like they can cause/assist with a lot of mutations, which I wasn't aware of.

And thank you for pointing me toward that Exon Junction Complex thing, I'll be checking it out.

>>8394021
Fuck, meant "said", not "read."

Sometimes the DNA is methylated and therefore locked' from being transcribed. Might want to look into this if you're interested.

http://www.nature.com/scitable/topicpage/The-Role-of-Methylation-in-Gene-Expression-1070

>>8394009
Do we now how many intrones does, for example, human DNA consist? I can't find numbers, it's only said that procaryotes have much less of them than eucatyotes.

>>8395368
Methylation is also used by bacteria to prevent their anti-phage endonucleases from damaging their own DNA

>>8395452
We don't even know exactly how many genes humans have yet. It won't be until after we know that that we can know exact data on introns