Fletcher Lab

Lab: Why aren't we on Bluesky? Dan: Umm. I don't follow Bluesky. Lab: But the rest of the world does. Scientists too. Dan: I see. What's your point? Lab: We should be on Bluesky. And join scientific discussions. Dan: I'm more the silent type. Lab: We'll run it. Dan: Go for it!

Congrats Deepak!

Congrats to Ojiugo Egeonu on her recent poster titled ‘Evaluating IL-1β as a Non-Invasive Biomarker of Endometriosis.’ She measured the inflammatory cytokine IL-1β in menstrual effluent and peripheral blood, exploring if menstrual fluid could offer a less invasive path to diagnosing endometriosis.

New paper out in Nature Communications! Tall bystander proteins block FcγR engagement in antibody-dependent phagocytosis, but engineering the membrane with tall binding proteins restores close contacts & rescues phagocytosis. Congrats to all the authors! www.nature.com/articles/s41...

Influenza A virus must cross the mucus layer to infect us. Our new preprint combines theory, simulations, and experiments to show how the virus can hijack this barrier to power its motion and follow receptor gradients—without an internal motor or signaling network. www.biorxiv.org/content/10.6...

Congratulations to Daniel Fletcher of UC Berkeley on being named a 2026 ASCB Fellow! https://www.ascb.org/society-news/fifteen-visionary-scientists-named-2026-ascb-fellows/

What if you had a light-triggered starting gun for #CRISPR diagnostics? Meet LUCas, a light-controlled #Cas13a system that stays silent until you need it. Now published in @narjournal.bsky.social. Congrats to all the authors! #moleculardiagnostics academic.oup.com/nar/article/...

Congrats Deepak (@deepakkrish.bsky.social) on starting your own lab. We could not be more proud of you!

Congratulations Andres! bio.bakarlabs.org/new-impact-g...

Congrats to MCB's Dan Fletcher & Roberto Zoncu @robzonculab.bsky.social on being named 2026 ASCB Fellows! 👏🎉@ascbiology.bsky.social

New preprint! Surface confinement reshapes CRISPR assay dynamics in ways solution-phase work never reveals. We built a multi-scale framework to capture those effects, then used it to develop SurfCas: a multiplexed bead-based Cas13a assay in a one-pot format. www.biorxiv.org/content/10.6...

We are recruiting participants for endometriosis research. Our lab is studying menstrual blood to develop better diagnostic and therapeutic tools for endometriosis. If you would like to participate, please complete this survey: redcap.berkeley.edu/surveys/?s=8... #Endometriosis #WomenHealth

Congratulations to Carlos (@carlosfng.bsky.social) for his doctoral hooding ceremony! #PhinisheD #PhD

A huge thanks to everyone who participated in the Fletcher Lab Art Show 2026! Your creativity, talent, and passion made this event truly special. Check out the Ground State Ensemble performance: youtu.be/h7E9Nld7mtk?...

Fletcher Lab members brought hand-held microscopes to the @exploratorium.bsky.social outreach event — putting the power to explore the microscopic world directly in people's hands. Huge shoutout to Michael Anne, Zaina, Andres, and Chunzi. ©Exploratorium, photo by Ida Tietgen Høyrup.

Congratulations to Carlos (@carlosfng.bsky.social) for being a recipient of the 2026 Outstanding Graduate Student Peer Mentor Award. Images courtesy of Laure Andrillon.

Congratulations Smiti (@smitim.bsky.social) for passing your qualifying exam! #PhDCandidate

Join us for the 22nd Fletcher Lab Artshow! We’re looking for artists to submit their work and be part of an evening celebrating creativity and community. We will also have the return of the Ground State Ensemble! Art by @chunzi-liu.bsky.social @qb3-berkeley.bsky.social @berkeleymcb.bsky.social

In our new work published in @natbiomedeng.nature.com in collaboration with @theottlab.bsky.social and @doudna-lab.bsky.social, we introduce "interfering" guide RNAs (igRNA) for CRISPR-Cas13a that regulate enzyme activity after activation. Congrats to all the authors! www.nature.com/articles/s41...

Happy #internationalwomensday to all of the incredible women, especially those from our lab (past and present). Your curiosity, creativity and determination continue to shape our science and community.

The NTDscope is a portable brightfield, darkfield, and fluorescence microscope used for diagnosing neglected tropical diseases (NTDs). This video shows S. mansoni miracidia. Check out our most recent publication: journals.plos.org/globalpublic...

Check out our latest preprint: LUCas! A direct light control of Cas13 trans-cleavage activity. Congrats to all the authors: Carlos (@carlosfng.bsky.social), Deepak (@deepakkrish.bsky.social), Andres, and Aymeric. www.biorxiv.org/content/10.6...

My choice last week in @science.org www.nature.com/articles/s41... Caitlin E. Cornell, Aymeric Chorlay, Deepak Krishnamurthy, Nicholas R. Martin, Lucia Baldauf & Daniel A. Fletcher

Preprint out now! Cell surfaces are crowded with tall proteins that block immune recognition. We discovered tall binding proteins create “stepping stones” that help short receptors engage, even in dense crowds. A new design principle for #immunotherapy. In memory of Phillip L. Geissler

☕Cornell et al. show that target cells with low cortical tension induce #macrophages to preferentially trogocytose, or engulf in small fragments, whereas target cells with high #CorticalTension tend towards #phagocytosis. bit.ly/3L7xFIO

How does a macrophage decide to eat or simply nibble? Check out our latest paper! You can also read this nice review. Congrats Caitlin for leading this amazing work! www.nature.com/articles/s41... www.nature.com/articles/s41...

Macrophages can engulf targets whole (phagocytosis) or nibble them in small fragments (trogocytosis), a decision controlled by cortical tension (hi favors former, low latter) www.nature.com/articles/s41... www.nature.com/articles/s41... @natcellbio.nature.com @ucberkeleyofficial.bsky.social

If you are going to #ASCB2025, check out some great talks and posters from our lab members

Happy Thanksgiving! Gratitude today for everyone pushing the frontiers of science in their different roles.

Check out our latest published manuscript: SurFlex microscopy, a new technique to measure molecular flexibility. Congrats to Aymeric, @sid592.bsky.social, @blenackmon.bsky.social, and Andres! www.pnas.org/doi/10.1073/...

Congratulations Dan for being elected to the National Academy of Medicine! bit.ly/4o0pDj5

Our team is developing portable digital microscopes that harness AI to automatically detect parasitic infections. This shows great potential to help public health programs expand access to affordable disease screening in low-resource settings. Link: tinyurl.com/4bazch67

Check out Siddhansh (@sid592.bsky.social) presentation at the 4th Physics of Life Symposium hosted by the #CZBiohubSF. youtu.be/b7G5wyE6iyo?...

Happy Postdoc Appreciation Week to all of our postdocs! #PostdocAppreciationWeek

Congratulations Kira for passing your qualifying exam!

Take a look at our newest published article in PLOS NTD: doi.org/10.1371/jour... #schistosomiasis #ML #diagnostics

Check out our most recent published paper in @natcomms.nature.com about the effects of cell surface crowding in cell-cell fusion: rdcu.be/ezCOF

Check out this talk by one of our amazing postdocs, Deepak! youtu.be/ErE3f5iyPio

Had fun at the MBL Physiology Course in Woods Hole! Chunzi, Elizabeth & Kira led creative rotations: • Trogocytosis is a mi(gh)t-y way to transfer • Sync(ytium) or Swim: Which fusogen will reign supreme? • Mucin Impossible: Eat up or get lost

Welcome to our new BioE Ph.D. students, Smiti and Michael Anne! @smitim.bsky.social

Congratulations Caitlin!!

Come to the Annual Fletcher Lab Artshow on Friday May 9th, 2025! We host this event yearly as an opportunity for folks to display their artwork, come together with wine and cheese, and admire artwork!

Come explore and be amazed on April 12 and 13 at the @exploratorium.bsky.social. This event is based upon work supported by the Center for Cellular Construction. #microscopy #Magnified

Congratulations to both Jared and Andres for passing their qualifying exams

🌟Say hello to Dan Fletcher @fletcherlabucb.bsky.social, a bioengineer renowned for developing novel experimental approaches and microscopy tools with far-reaching impacts on our understanding of infectious diseases, immunology, and cancer biology. 1/

preLights in cell biology (Feb 2025) This article lists the recent @prelights.bsky.social posts that discuss #preprints in #cellbio. Featured #preLight by @fadelvalle.bsky.social covering work on macrophage trogocytosis from @fletcherlabucb.bsky.social. journals.biologists.com/jcs/article/...

Some lab members and friends attended the #StandupforScience protest.

“We have a role to play in making the world a better place.” Thank you to #RhodesScholar Professor Dan Fletcher for hosting our partners Schmidt Science Fellows at UC, Berkeley for another year as part of the Science Leadership Program. @fletcherlabucb.bsky.social 📷 @claudinegossett.bsky.social

Fun story from the Fletcher lab showing that surface crowding is a major impediment to cell-cell fusion and myoblasts reduce their surface crowding to improve fusion! www.biorxiv.org/content/10.1...