🚨🚨Preprint alert!🚨🚨 We removed the main centromere 3 domain of Drosophila‼️ We designed an inducible dCas9-Fok1 system to cut 🧬 at unique sequences flanking the ~50-kb island where most of CENP-A sits. To our knowledge, this has never been attempted in a living animal!

Let my toddler pick the birthday card for his friend and he wanted to get the one with the cat 😝

Nobody move!

Come be my colleague at UCSF! Our department BTS (like the K-pop band, but aka Bioengineering and Therapeutic Sciences) is searching for TWO new faculty members. Links, timeline, and why two searches in this thread 🧵

And most definitely the economics prize

Corollary: it will also be within a week of the next grant deadline

If you can donate to your local food bank now is the time

Protamines sound super cool, because they are, they evolve, superfast, and are of the first examples of positive selection at the gene level!

Will anyone ask Trump or @MarshaBlackburn or @BrentTaylorTN about this today? Seems like a clarksville type Q 🤷🏼

There's something beautiful about sitting at the confocal and visualizing different cell types, different tissues, different ideas .... It's such pure joy. Science is beautiful as it is. I hope we are able to protect this experience - esp in light of recent events of AI usage for image processing.

I mean, there is a giant corn in the middle, so...

TL:DR; male fertility essential protamines still evolve fast because they are in an arms race with selfish genes on the sex chromosomes. Although Mendelian inheritance is ubiquitous, it is a fragile truce and itself is a Red Queen conflict: running hard to keep in place

That is meiotic drive. Something (we think Y-linked) kills sperm that carry a target on the X. Mst77F protects them. Fused sex chromosome (attached X^X and attached X^Y) crosses back this up. We do not know the target yet but we ruled out the obvious suspect: a giant satellite repeat on the X.

We took a fly protamine, Mst77F, which is both essential for male fertility in D. melanogaster and among the fastest-evolving genes, and swapped in versions from related species. We also halved its dose. In both cases, sperm carrying the X chromosome were slower at compacting their DNA.