Sophie Miller - Three Minute Thesis - 4/25/2023

we spend a third of Our Lives asleep if our prehistoric ancestors could have survived without sleep Evolution probably would have taken care of this massive inefficiency for us clearly there's something biologically important about sleep since every creature in the animal kingdom does it but we don't have to look that far to know how critical sleep is because especially here at Caltech we all know what happens

when we don't get enough of it yet even though we spend so much of our time in this bizarre state of unconsciousness much of the why and how of sleep remain a mystery the first scientists to begin to tackle these questions have been biologists who study the genes in our DNA and the circuits in our brain that are involved in sleep but the genes in our

the molecular level the molecules I'm most interested in studying are proteins proteins are the molecules in our cells that do things they're the signaling molecules enzymes Transporters structural components and antibodies for my PhD I investigate what protein cells produce during the night and how that differs from the protein cells produced during the day to do this I use the model organism called zebrafish because believe it

or not we actually have a lot in common with these creatures zebrafish have a lot of the same genes known to play a role in sleep in humans like melatonin serotonin and hypocratin and as early as four days old the larvae start exhibiting patterns of sleep at night and wait during the day just like us but before I when I came to this project there was

no way of picking apart what was being produced when well we could get a snapshot at a moment in time of all the proteins in the fish there was no way of distinguishing between which proteins were made at night and which were made during the day to do this I use a cool new method for my lab it works by using a tagged version of the

building blocks that make up proteins which I give to the fish during the time window I'm interested in studying the fish then incorporate this tag into proteins as they're being made and the tag then allows me to pull out the newly made proteins from the pool of pre-existing proteins I can then identify these proteins using an instrument called the mass spectrometer which allows me to detect

exactly which proteins were present in each sample and their relative amounts using this technique I've identified thousands of proteins synthesized during day and night and this data set which I've only just started to dig into will allow us for the first time to identify which molecules are uniquely synthesized during sleep and which during wake what excites me most though about this data set are the questions

that arise from it which proteins what is the function of the proteins made at night and how does that differ from those made during the day and do proteins make at night directly facilitate sleep or do they require sleep to be produced I hope to answer some of these questions and in doing so shed some light on the sleep we get at night thank you [Music]