Lecture 11, concept 10: Homologs, orthologs & paralogs

[@madkatt333]

Good video but the markers make a lot of noise.

[@deshonjoseph8316]

lol. I knew someone was going to talk about that

[@mohammedelbekkal6079]

How this man write this way, impressive

[@elianatejera7718]

I think it's mirrored, he writes normally but flips the video so we can read

[@randomshittutorials]

I needed this video. Others are so confusing. This was clear and simple. My brain just doesn't understand sometimes lol.

[@fede8327]

Same!!!

[@FieldsDynamic]

Thanks for amazing videos. Really impressive.

[@lol_marshy]

more videos like these. this is great. thanks

[@keityfarfan1472]

Thanks for this video! It's an excellent explanation! :)

[@aminaelhannaoui7523]

great and simple explanation, thank you!

[@BearersNetwork]

Thank you for this explanation😊

[@applepie4585]

Is orthologous protein a homologous protein/gene with the same function in different species, whereas homologous proteins do not necessarily need to have the same function? Also, is a paralogous protein a type of homologous protein? Thanks!

[@laurincarmichael9921]

Great explanation but the squeak of that marker is killing me.

[@jenko1017]

Great video teach! However I do recommend you do something about the squeaking noise, its really irritating

[@eriklindahl]

Not trivial to solve with equipment I'm afraid, since the setup requires fluorescent markers writing on smooth glass. However, next time I record a class I'll see if it's possible to use a low-pass filter or some sort of AI-based denoiser.

[@hyperduality2838]

Orthologs are dual to paralogs synthesize homologs (isomorphologs).

[@freefiretv7029]

MAN ,your are AWEEEEEEEEEESOME ❤❤🔥🌠

[@julianaGonzalez-p7n]

very useful!

[@danpaulisbitski]

If proteins have common ancestry and universal common ancestry is true then why do we find that some proteins don’t have homologues? Does that support separate ancestry for those proteins?

[@danpaulisbitski]

It sounds like parologs is more of an assumption than homologs. Have we observed parologs in the lab?

[@eriklindahl]

Well, my first argument would be that "common ancestry" refers to an organism, not necessarily every protein in it. However, the more boring scientific answer is that we really only care about homology in the sense of whether we can detect it or not (through sequence similarity). Once we get to the point where we can't really detect it (statistically), it becomes more of a philosophical question, and entertaining as it might be, it's not really something that we worry about in practice - precisely because we can't compute it anyway :-)

[@danpaulisbitski]

@@eriklindahl Thanks for responding and might I say seemingly very honestly. It’s rare to bring up a possible argument against universal common ancestry and not get attacked for it. LOL!

[@Eunice-tp2vm]

thank you! it's so helpful :)

[@jeffreychiu3730]

Aren't everything living homologs :D. I assume when we talk about homologs we have a timeframe in mind?

[@eriklindahl]

Homology refers to proteins/genes, not the entire organism :-)

[@danpaulisbitski]

What makes a Neanderthal a different species than a Homosapien? I thought they were just different people groups that interbred with each other?

[@eriklindahl]

The usual biological definition is that species are defined by reproductive isolation, i.e. the ability to breed. There's some evidence that humans and neanderthal were actually able to have children together, which would mean we're the same species, and only different subspecies.

[@eriklindahl]

So, in brief: With neanderthals the definition is not entirely clearcut. Some scholars consider them different species, other just subspecies.

[@danpaulisbitski]

@@eriklindahl That’s was my thoughts as well. Thanks again

[@aiden__9331]

The sound of marker on glass made me deaf.

[@annakotova3508]

The explanation is great but the sounds of your writing are unbearable!

[@eriklindahl]

I'm afraid that's a shortcoming of all the lightboard solutions for now - there simply aren't any good fluorescent markers that both produce clearly visible text/symbols and don't squeak when you write on glass. Sorry :-)

[@aminaelhannaoui7523]

yeah its pretty jarring but on the upside, it definitely has me paying attention! 😂

[@jesseward-bond2165]

@@eriklindahl Not sure how you process your audio, but a low-pass audio filter might do the trick. Could do it using Audacity (free).

[@zahraammadani]

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