Maxence Lejars

beautiful work by Gaurav Dugar, who taught me my first RNA stuff and even a bit of Campylobacter :)

Starvation-independent alarmone production inhibits translation through GTP depletion in Bacillus

#MicroSky

Bidirectional promoters in Escherichia coli: regulatory rules and implications for gene expression noise Abstract. In prokaryotes, bidirectional promoters are pseudo-symmetrical DNA sequences that stimulate divergent transcription. Ubiquitous, and far more lik

@ewarman.bsky.social has followed up on her discovery of bidirectional promoters in bacteria by defining their basic rules for regulation and links to gene expression noise...

academic.oup.com/nar/article/...

RNase Y mutations and RNA turnover optimization as a possible pathway for ATB tolerance

Evolution and diversity of oxidoreductases involved in redox balance and energy conservation - Nature Ecology & Evolution HORBEC are protein complexes involved in the regulation of redox balance and energy conservation. The authors develop a bioinformatic tool for HORBEC annotation in bacterial and archaeal genomes and r...

Passioned by #bioenergetics? Do not miss our new article on the evolutionary history of oxidoreductases with G. Borrel and @sgribaldo.bsky.social @archaeal.bsky.social @valdeanda.bsky.social @pasteur.fr @cnrs.fr @cnrsbiologie.bsky.social @natecoevo.nature.com (www.nature.com/articles/s41...).

Why m⁶A? An RNA surveillance model Dierks and Schwartz discuss the m6A surveillance model, proposing that m6A flags “undesirable” intron-less RNAs (e.g., transposons) for decay. This provides a mechanism to distinguish “legitimate” spliced mRNAs and potentially suppress harmful RNA.

Online Now: Why m⁶A? An RNA surveillance model Online now:

#Microsky

Reposting just for the title!

Integrated fluorescence light microscopy-guided cryo-focused ion beam-milling for in situ montage cryo-ET Nature Protocols, Published online: 30 January 2026; doi:10.1038/s41596-025-01284-zA protocol for cryogenic 3D correlative focused ion beam milling using an integrated fluorescence light microscope and montage cryo-ET for nonadherent and adherent mammalian cells, as well as primary Drosophila melanogaster neurons.

New Article! Integrated fluorescence light microscopy-guided cryo-focused ion beam-milling for in situ montage cryo-ET

Combining super-resolution imaging and machine learning, we reveal that C. thermocellum shifts from a microbe-mediated strategy to dynamic cellulosome redistribution during growth on insoluble substrates.
www.life-science-alliance.org/content/9/3/...

Polyamine sensing by nascent ornithine decarboxylase antizyme stimulates decoding of its mRNA - Nature Ornithine decarboxylase (ODC), the rate-limiting enzyme in the biosynthesis of polyamines, is regulated by an antizyme (OAZ). Polyamines induce antizyme expression by promoting ribosomal frame-shiftin...

Many many moons ago I fell in love with science while working on how Polyamines regulate programmed ribosomal frame shifting

www.nature.com/articles/nat...

Time to get back to these fascinating and complex field

Raman spectroscopy can be used to predict cellular physiology and proteome composition in E. coli.

🔗 buff.ly/bcALp6R

“A student joining a lab is often presented with a hypothesis to work on and may see science as a hypothesis-testing endeavor. Many young postdocs have been told that as a PhD student their job was to answer questions—now they have to discover their own unknown unknowns.”

🧫🧪

Large-scale testing of antimicrobial lethality at single-cell resolution predicts mycobacterial infection outcomes - Nature Microbiology Via high-throughput imaging and tracking over 140 million single mycobacteria, the authors show that drug- and strain-specific killing predict treatment outcomes, with potential to improve drug develo...

#microsky

www.nature.com/articles/s41...

Novel estimation of memory in molecular dynamics with extended and comprehensive single-molecule tracking software: FreeTrace Single-molecule tracking (SMT) in live cells reveals how biomolecules explore crowded intracellular environments, yet most tracking software assumes Brownian motion, an approximation that fails when a...

Its been a pleasure to be a part of this work.

Our group, and in particular Junwoo Park, describes a powerful tool to study single-molecule tracking. FreeTrace reconstruct trajectories under fractional Brownian motion, which enabled us to study anomalous diffusion 🔬

www.biorxiv.org/content/10.6...

New Microbe Matters!

@relenski.bsky.social traces the legacy of Escherichia coli and how science is evolving to use this model organism in new ways

#microsky

www.nature.com/articles/s41...

RNA-triggered Cas12a3 cleaves tRNA tails to execute bacterial immunity - Nature Cas12a3 nucleases constitute a distinct clade of type V CRISPR–Cas bacterial immune systems that preferentially cleave the 3′ tails of tRNAs after recognition of target RNA to induce growth arres...

#microsky #phagesky #phage defence

www.nature.com/articles/s41...

A 5′-UTR cis-acting RNA element targeted by RNase III is essential for DNA simple sequence repeat-dependent phase variation in Haemophilus influenzae Abstract. Simple sequence repeats (SSRs) are insertion-deletion mutational hotspots causing phase variation in bacterial genomes. When located in intergeni

A 5′-UTR cis-acting RNA element targeted by RNase III is essential for DNA simple sequence repeat-dependent phase variation in Haemophilus influenzae

academic.oup.com/nar/article/...

A toxin/antitoxin system targeting the replication sliding-clamp induces competence in Streptococcus pneumoniae Author summary The environment in which bacteria live puts them under a great deal of stress, forcing them to adapt constantly, either temporarily or permanently. Streptococcus pneumoniae, a pathogeni...

Delighted to share a new paper from our lab, a study led by Mathieu Bergé looking at how an endogenous toxin targets replication to induce competence in the pneumococcus. dx.plos.org/10.1371/jour...

+ a large dataset to explore!

Beautiful story!

fans of two component systems (TCS) take note 👇
#MicroSky

Final version is out! Our large-scale cryo-ET dataset 🔬 of Chlamydomonas reinhardtii 🦠 is now published in @cp-molcell.bsky.social

Huge collaborative effort! So glad to see the community already using it to develop new resources & tools.

Check it out here: shorturl.at/z4i4c
#CryoEM #CryoET

Phage-encoded small RNA hijacks host replication machinery to support the phage lytic cycle Using RIL-seq, Silverman et al. map the RNA interactome of E. coli during phage lambda infection and uncover a conserved phage-encoded sRNA that activates host replication machinery. Their findings re...

Do viruses use RNA to rewire bacteria?
Yes!
In our paper in @cp-molcell.bsky.social RIL-seq reveals interkingdom RNA interactions during λ infection. Phages don’t just encode proteins, they use small RNAs to hijack bacterial replication and fine-tune infection.
#RNA #Phage
doi.org/10.1016/j.mo...

RNA–RNA interactome approaches provide in vivo evidence for a critical role of the Hfq rim face in sRNA–mRNA pairing Abstract. Most bacterial small regulatory RNAs (sRNAs) modulate gene expression by forming complementary base pairs with target messenger RNAs (mRNAs), dep

RNA–RNA interactome approaches provide in vivo evidence for a critical role of the Hfq rim face in sRNA–mRNA pairing url: academic.oup.com/nar/article/...

Beyond RNA modification: a novel role for tRNA modifying enzyme in oxidative stress response and metabolism Abstract. RNA modifications play a fundamental role in regulating essential cellular processes, including translation fidelity and stress adaptation. While

Our new paper on DusB’s role in redox metabolism in V. cholerae is now out in @narjournal.bsky.social linking tRNAmodif enzymes and metabolic adaptation.

Beyond RNA modification: a tRNA-modifying enzyme shaping oxidative stress resilience and metabolism in V. cholerae #rnasky #rnabiology

😊🦠💫

After D2449 by rdsA, now new methylations in E.coli rRNA under stress 💫

Bio-essential sugars in samples from asteroid Bennu - Nature Geoscience Samples returned from asteroid Bennu contain bio-essential sugars such as ribose and glucose that may have formed in the parent asteroid from brines containing formaldehyde, according to a geochemical...

Ummm guys, we've just found ribose (sugar in RNA) and glucose on an asteroid www.nature.com/articles/s41...

Screenshot from GRC portal confirming microbial population biology meeting June 27, 2027 in Andover, New Hampshire.

It’s officially happening folks! The Microbial Population Biology Gordon Research Conference is back in Andover, New Hampshire starting June 27th of 2027!
See you there!!

@wcratcliff.bsky.social @ksbakes.bsky.social @surtlab.bsky.social

#microsky #mevosky