Mark Rebeiz
@rebeizlab.bsky.social
370 followers 300 following 13 posts
Laboratory of Mark Rebeiz (he/they), studying the evolution and development of morphological novelty in Drosophila at the University of Pittsburgh. Rooting for team human. https://rebeizlab.weebly.com/
Posts Media Videos Starter Packs
rebeizlab.bsky.social
Really excited for PASEDB2025 in July!
evodevopanam.bsky.social
😊 Friendly reminder!

⌚️The registration deadline for the PASEDB 2025 Miami meeting is Friday June 20, 2025

Become a member: panamevodevo.org/membership.h...

Register here: evodevo.wildapricot.org/event-6007396

#pasedb #evodevo
Reposted by Mark Rebeiz
evodevopanam.bsky.social
🐟 I’ve been herring all about it!
Fish satellite symposia speaker talks at #PASEDB

Invited speaker: @fishevodevogeno.bsky.social

Organizers: @nakamuralab.bsky.social @patyschneider22.bsky.social & Joaquín Letelier

Register: evodevo.wildapricot.org/event-6007396
Reposted by Mark Rebeiz
evodevopanam.bsky.social
🌟Remember to register #PASEDB 2025 Biennial Meeting (July 22-25)!

We have an incredible line up of activities and speakers, including 4 satellite symposia (July 22): Spiralia🐌, Arthropods🦋, Fishes🐟 and Non-bilaterian 🪸

Register and submit today!
evodevo.wildapricot.org/event-6007396
The Pan American Society for Evolutionary Developmental Biology - 2025 Biennial Meeting of the Pan American Society for Evolutionary Developmental Biology
evodevo.wildapricot.org
Reposted by Mark Rebeiz
evodevopanam.bsky.social
🌟We have great satellite meetings!🥳😎

- Spiralia 🐌🪱
- Arthropods 🦋🦗🪰🪳
- Fishes🐠🐟🐡
- Non-bilaterian 🪼🪸

Remember to register here: evodevo.wildapricot.org/event-6007396

#evodevo #pasedb #science
rebeizlab.bsky.social
Thanks so much Amber! Hope you are having an awesome time in your postdoc!
rebeizlab.bsky.social
BTW our bad - Gavin's handle is @gavinrrice.bsky.social
rebeizlab.bsky.social
Thank you to the O'Connor-Giles lab for updating the incredible CRISPR Optimal Target Finder to include D. eugracilis. @bdsc.bsky.social for lines, and @flybase.bsky.social for being our favorite database
rebeizlab.bsky.social
We want to thank our amazing collaborators Julia Zeitlinger and Tatiana Gaitan. We cannot wait to share more as we continue to dive deeper into how the trichome genetic network has specialized!
rebeizlab.bsky.social
Our results demonstrate the power of genetic network co-option to redeploy a genetic network into a new tissue context. Yet, novelties are more than mere iterations of repeated structures. We reflect on how they derive unique features by elaborating their network architecture.
Schematic representation of the origin and specialization of the D. eugracilis aedaegal sheath trichomes and its genetic network
rebeizlab.bsky.social
Misexpression of the active form of shavenbaby in the naïve aedeagal sheath of D. melanogaster was sufficient to induce small trichomes.
This is one of the first times that genetic network co-option has been recapitulated through experimental manipulations.
induction of ectopic trichomes in D. melanogaster by mis-expressing shavenbaby.
rebeizlab.bsky.social
Disruption of shavenbaby via mosaic CRISPR caused the truncation of trichome height, showing the important role of shavenbaby, but also indicating that there are likely other redundant transcription factors as well
adult aedaegal sheaths of D. eugracilis control and shavenbaby CRISPR treatments which reduced height of the largest trichomes.
rebeizlab.bsky.social
Additionally, we find that the trichome genetic network was partially co-opted into the aedeagal sheath as 14 (purple) out of 23 direct targets of shavenbaby we tested have gained expression in the D. eugracilis aedeagal sheath
shavenbaby GRN showing multiple downstream functions (ECM, actin and "other".
rebeizlab.bsky.social
The novel unicellular outgrowths of D. eugracilis have evolved expression of the key trichome transcription factor shavenbaby, named for its mutant phenotype, in which trichome morphology is disrupted
expression of shavenbaby protein (top) and mRNA (bottom) in D. melanogaster (no expression in the sheath) and D. eugracilis (expression in the sheath - outlined)
rebeizlab.bsky.social
We found that each of these outgrowths develop as an actin-rich (magenta) extension of a single cell (apical cell junctions grey), similar to trichomes, hair-like structures that cover the larvae and much of the adult cuticle
rebeizlab.bsky.social
We developed the rapidly evolving drosophilid terminalia as a model to explore the genetic basis of novelty. D. eugracilis has over 150 differently sized outgrowths on its aedeagal sheath which appear to be absent from other species of Drosophila, including D. melanogaster.
The adult aedeagal sheaths of D. pseudoobscura, D. ananassae, D. melanogaster, and D. eugracilis (which is the only species with a variety of differently sized outgrowths).
rebeizlab.bsky.social
Our new @CurrentBiology paper provides a rare glimpse into a morphological novelty in Drosophila eugracilis
In it, @gavinrrice and colleagues, infer and reproduce the likely initial steps of a novelty's formation
www.sciencedirect.com/science/arti...
3D micrograph of the developing D. eugracilis terminalia