Nicole King (UC Berkeley, HHMI) 2: Choanoflagellate colonies, bacterial signals and animal origins

www.ibiology.org/ecology/choa...
Talk Overview:
Animals, plants, green algae, fungi and slime molds are all forms of multicellular life, yet each evolved multicellularity independently. How did animals evolve from their single-celled ancestors? King addresses this question using a group of fascinating organisms called choanoflagellates. Choanoflagellates are the closest living relatives to animals; they are single-cell, flagellated, bacteria eating organisms found between fungi and animals on the phylogenetic tree of life. By sequencing the genomes of many choanoflagellate species, King and her colleagues have discovered that some genes required for multicellularity in animals, such as adhesion, signaling, and extracellular matrix genes, are found in choanoflagellates. This suggests that these genes may have evolved before the transition to multicellularity in animals.
The choanoflagellate S. rosetta can exist as a unicellular organism or it can switch to form multicellular colonies. In fact, its life cycle can be quite complex; it can form long chain colonies, spherical colonies called rosettes, or exist in different unicellular forms.
In part 2 of her talk, King explains how she chose to use S. rosetta as a simple model for animal origins. After overcoming the technical difficulty of getting S. rosetta to form rosettes in the lab, she investigated how rosettes develop and how the cells within a rosette adhere to each other. She also asked the intriguing question “What regulates rosette development?”. It turns out that rosette formation is regulated by lipids produced by environmental bacteria that S. rosetta eat. This result adds to the growing interest in how bacteria may be influencing the behavior of diverse animals including humans.
Speaker Biography:
While fossils sparked Nicole King’s childhood interest in evolution, she realized that the fossil record doesn’t explain fully how animals first evolved from their single celled ancestors. To answer this question, King decided to study modern day choanoflagellates. Choanoflagellates are single celled organisms that can also develop in to multicellular assemblages.
King first learned about choanoflagellates while she was a graduate student with Richard Losick at Harvard University. She moved to the University of Wisconsin-Madison to do a post-doctoral fellowship focusing on choanoflagellates. In 2003, King joined the faculty at the University of California, Berkeley. Currently, she is a Professor of Molecular and Cell Biology at Berkeley and a Howard Hughes Medical Institute Investigator.
King’s innovative studies have been recognized with a MacArthur Foundation Fellowship and a Pew Scholarship. King is also a Senior Fellow of the Canadian Institute for Advanced Research.

[@TS-wf2rn]

Fabulous content! Like a good book you can't put down, I had to watch both parts of your lecture one after another. Brings so much wonder to my mind. Thanks for sharing!

[@MrRobertX70]

This was incredibly interesting. I think that I love choanoflagellates.!

[@trekpac2]

As a plant specialist, this was one of the most interesting presentations that I have listened to recently. Your studying the mechanisms for the formation of multicellular organisms has revealed a lot to scientists. Just great.

[@celldrwu]

That was truly fascinating! I also loved the stories of frustration and triumph of getting the cultures to form rosettes: so many stories in science are this way. Can't wait to hear updates on the research!

[@roberttwigg7295]

Thanks Nicole - A couple years ago I included you and your findings in my book. I appreciate all the work you have put into your discovery.

[@roberthfagundes5145]

Thank you so much for this talk, and congratulation to Dr. Nicole King for this incredible work

[@andreewendel5048]

Thank you very much for charing this fascinating discovery with us.

[@kalailyliani1021]

Thanks, Dr. King. Truely astonishing

[@corneliusprentjie-maker6715]

Thank you Nicole King. it is nice to see hard work and perceverance come too fruition. Ready for questions?

[@StewartChaimson]

Thank you! Very enjoyable seminar!

[@mrhdbnger]

Just mind blowing. I was on the edge of my seat with the part about the lipids being rosette inducing and how you were able to isolate those AND find their antithesis. It really was like a microscopic murder mystery. Who made the rosettes? Thank you for these videos.

[@davidrosen5137]

Thank you! Great talk; fascinating research!

[@doanviettrung]

Fascinating! BTW, she said "serendipity", but that's 1%, and 99% was hard work.

[@SergioDPerez-rm3dk]

That's exactly what serendipity means

[@corneliusprentjie-maker6715]

Such a pleasant surprise. and reward for being interested in creation. :)

[@alessandroclochiatti2160]

wonderful presentation :)

[@nextworldaction8828]

Really great!!! 💥

[@Arturito0350]

This is great, thank you so much

[@apepchoko]

Gracias por hacer tan accesibla esta interesante información👍

[@SteveHazel]

MORE PLEASE :)

[@Cr_starkov]

Thanku for this usefull informarions.i learn lot

[@numericalcode]

I have a lot more respect for choanoflagellates now!

[@penaryproductions2275]

Part 2!

[@saxoman1]

This is amazing! Thank you! I wonder if we could get a lecture on the common ancestor of vertebrates and invertebrates! Something that's hard to come by (at least on youtube and online forums).

[@patldennis]

There is no common ancestor of invert and vertebrates since vertebrates are just a derivation or nested group within invertebrates. Vertebrates are just a special kind of chordate and most chordates are actually invertebrates.

[@saxoman1]

@@patldennis I know this is like 2 years later (hope you're well!) thanks for this reply! I now know that the real distinction I was looking for was protostomes vs deuterostomes! And have found the related info, always fascinating!

[@patldennis]

@@saxoman1 Just as long as you realize not all deuterostomes are vertebrates. The most we can know about tge common ancestor of proto- and deutero- was that they descend from a bilaterian.

[@saxoman1]

@@patldennis yup! I learned that too along the way! Basically, for the question I asked, vertebrate/inbertebrate framing was incorrect. Another fascinating thing!

[@robertlipka9541]

One question not covered in the presentation: apart from the process what is the reason that the choanoflagellate forms rosettes? What advantage if any does it gain?

[@patldennis]

Teamwork makes the dreamwork. It's a more efficient feeding apparatus

[@corneliusprentjie-maker6715]

So that suggests culture? adapting survival stratagem tonsuit environment...

[@craiglilly3657]

Very good interesting! Do you have any insight into when gastrulation might occur? Once you have a ball of cells that would seem to be the next step for an animal.

[@angelochiantera1820]

Grazie!!!!

[@ewaozga6354]

I am a bit confused why different bacteria from gut is important to check if it causes rosettas?

[@reikasamaendsupwithshousuk2889]

I have questions professor, what is the benefit of being colonial for the choanoflagellates and do they form chain colony thrpugh the same process as the rosette colony?

[@StanislavMudrets]

I wish she told us what the function of the roseta formation is.

[@corneliusprentjie-maker6715]

i think in the precious video it shows relation to coral where the funnel the water to eat bacteria... but "do they then not eat their horses...but they do eat their cows?" i also had the impression it was thought they come first from the roseta form. then become free living. *so i'll have to watch again. Good work though! so jealous! :p ir

[@ardd.c.8113]

Jon clardy lab does great work

[@jomen112]

Big question;how far away are we from understanding how to turn S. rosetta into pork shops?

[@robertlipka9541]

Simples... she answered it: wait between 1 billion and 500 million years and something like pork chops becomes available.

[@MEGAJACAREI]

Hi i wonder if the weather is inventing itself to get the clonoflageles swim without water or in wheather undisdinguosheble to the eye conditions

[@mr.wrongthink.1325]

She is smart and cute.

[@ralphbucao9044]

Now. Not Now.