Yeah, we also put a disclaimer in the discussion that people that take part in our experiment probably already are biased towards wanting something different. However, it was also extra work for everyone, so it might have made them grumpy about it in the process 😉.

Not sure whether I’d call it an intervention study - more a comparative study. In several of our assessments we asked authors as well as reviewers to compare the discovery stack system with traditional review. Not the most perfect control, of course.

Results of the yearly Rauch-Pruneda carving party

🙋‍♀️

I want to highlight again that this was an excellent collaboration building on Genentech's screening and ubiquitin and my lab's organoid and infection expertise.
Rockstar graduate student Marin Miner and techs Rachael Peterson and William Scott did all the real work in the Rauch lab!

8/8 The END

Indeed! NleL deficient bacteria cause more cell extrusion than WT in organoids, and less epithelial colonization in vivo.
In mice deficient in ROCK1/2 in gut epithelia, the disadvantage of NleL deficiency is gone!
Thus, bacteria use NleL to suppress epithelial extrusion, which aids in spread!

7/8

These kinases had already been implicated in apoptotic cell extrusion. We show in organoid models that they are also needed for rapid extrusion post inflammasome activation. During epithelial infection with Citrobacter (an E.coli relative), they are degraded.
Will this have consequences?

6/8

Originally, Giovanni was screening for inflammasome inhibitors among E.coli effectors, using LPS induced cell death as readout.
NleL, a known ubiquitin ligase, was a hit. MS analysis and WB show it ubiquitinates and thus degrades Caspase-4.

But it ALSO targets kinases ROCK1 and ROCK2?

5/8

But what about signals further down in the extrusion pathway? To remove the infected cell from the mono-layered intestinal epithelium without causing a leaky hole, the extruding cell and it's neighbors have to rapidly rearrange their cytoskeleton.
Cue our new story:

4/8

This protection through the inflammasome creates evolutionary pressure on pathogens.
Accordingly, there’s examples of bacterial attack on inflammasome components, such as Shigella degrading human Gasdermins and antagonizing Caspase-4.

3/8

2017 we showed intestinal epithelial cells rapidly extrude into the lumen after NAIP–NLRC4 activation, which protects from Salmonella.
We built on work from @leighknodler.bsky.social +@sellinlab.bsky.social.
Later, @psmitchej.bsky.social showed this as the reason for mouse Shigella resistance!

2/8

Archie says, "You got this!"