Peter Andersen

Final version @nature.com of our paper describing unconventional multicellular development in a choanoflagellate inhabiting an extreme environment. A ton of new data since the first @biorxivpreprint.bsky.social preprint (which we've kept updating).

A brief 🧵 (carried over from the old place)

We wrote a piece on how easy it is to write gene regulatory sequences. - Turns out, it isn't that easy even though we know a lot about cis-regulation.

huge credit to @carldeboer.bsky.social to seeing this through so our thoughts aren't lost. I promise, it's a worthwhile read!

I’m thrilled to share that my PhD work has been just published in Cell. After a long and bumpy ride, we uncovered the core function of nuclear speckles -splicing of GC-levelled exons- and traced the evolution of this gene architecture and condensates themselves to amniotes.

1/New preprint just dropped! 🔥🔥 We investigate how the genome is destroyed in apoptotic cells in a way that prevents DNA fragments from spreading beyond the dying cell 🧬⚰

Done here at @imbavienna.bsky.social & in the super @rcollepardo.bsky.social & Rosen labs:

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

Have you ever wondered 🤔... Does phenotypic variance respond to environmental perturbation? Does it have a genetic basis? Are mean and variance regulating loci exposed to different selection pressures? These and more questions are explored in our new preprint 🔥

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

Join us for a day of talks, posters, and discussions, featuring a morning joint lecture with Nobel Laureates Eric F. Wieschaus and Christiane Nüsslein-Volhard!
Date: Monday, May 4th, 2026
Location: University of Copenhagen, Mærsk Tower
sites.google.com/view/emergin...
Free to participate

Mutation can be stranded (e.g. APOBEC3G C>U on (–) DNA during RT) – but maybe not a general mech..

There are also retroviruses w other nucleotide biases (e.g. HTLV's C bias), so specific composite models for each virus seem likely imo (mut bias, RT effic, codon selection, defence avoidance, etc).

Excited to announce the upcoming Jacques Monod Conference on the mechanistic and evolutionary basis of programmed DNA elimination (Sept 21–25, 2026):
cjm.sb-roscoff.fr/en/conferenc...
Organized by @laurarossevo.bsky.social and myself.

So excited to share this manuscript led by the inimitable Cara Brand, who discovered that Topoisomerase II evolution causes hybrid female lethality in Drosophila.

Congrats to Cara, @nickbr0wn.bsky.social, Anirban, and
@buszczaklab.bsky.social!

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

Really looking forward to reading this in detail. Congrats to all of you 🥳

🔬 Recruiting a Postdoc!!!!
I’m looking for a motivated postdoc to join my lab and work on characterizing the role of a heterochromatin protein involved in a sex-ratio meiotic drive system in Drosophila.
If you know someone who might be interested, please share widely!

The political effects of X's feed algorithm https://doi.org/10.1038/s41586-026-10098-2 Received: 16 December 2024 Accepted: 4 January 2026 Published online: 18 February 2026 Open access • Check for updates Germain Gauthier,5, Roland Hodler?5, Philine Widmer35 & Ekaterina Zhuravskaya3,4,5 m Feed algorithms are widely suspected to influence political attitudes. However, previous evidence from switching off the algorithm on Meta platforms found no political effects'. Here we present results from a 2023 field experiment on Elon Musk's platform X shedding light on this puzzle. We assigned active US-based users randomly to either an algorithmic or a chronological feed for 7 weeks, measuring political attitudes and online behaviour. Switching from a chronological to an algorithmic feed increased engagement and shifted political opinion towards more conservative positions, particularly regarding policy priorities, perceptions of criminal investigations into Donald Trump and views on the war in Ukraine. In contrast, switching from the algorithmic to the chronological feed had no comparable effects. Neither switching the algorithm on nor switching it off significantly affected affective polarization or self-reported partisanship. To investigate the mechanism, we analysed users' feed content and behaviour. We found that the algorithm promotes conservative content and demotes posts by traditional media. Exposure to algorithmic content leads users to follow conservative political activist accounts, which they continue to follow even after switching off the algorithm, helping explain the asymmetry in effects. These results suggest that initial exposure to X's algorithm has persistent effects on users' current political attitudes and account-following behaviour, even in the absence of a detectable effect on partisanship.

A new paper shows that less than 2 months of exposure to Twitter’s algorithmic feed significantly shifts people’s political views to the right.

Moving from chronological feed to the algorithmic feed also increases engagement.

This is one of the most concerning papers I’ve read in awhile.

Time-calibrated phylogeny of the family Drosophilidae showing major species groups, surrounded by representative adult flies that highlight the remarkable morphological diversity of this model insect group. The composite image was created using Microsoft PowerPoint. Fly photographs were taken by Darren J. Obbard and are published under the Creative Commons Attribution License with permission.

The #fly community aims to achieve a comprehensive genomic study of the Drosophilidae family. @pankajd.bsky.social @bernardkim.bsky.social @petrovadmitri.bsky.social @darrenobbard.bsky.social present a comparative gene annotation for 301 #Drosophilidae species @plosbiology.org 🧪 plos.io/4c3pyrI

EMBO Press co-evolves with molecular ecology and evolutionary biology - The EMBO Journal The EMBO Journal - Molecular ecology and evolution are central to understanding how biological systems function, interact, and diversify. A special issue of this journal reflects the growing...

Read how @embopress.org is expanding its focus on molecular ecology and evolution as central underpinnings of functions/interactions/diversification of biological systems – by @yehumoran.bsky.social, @berndpulverer.bsky.social, and our new team of Editorial Advisors
link.springer.com/article/10.1...

A 🆕 #Ichthyosporea story
Led by@margaridaaraujo.bsky.social, in Co. @gautamdey.bsky.social & @hiralshah.bsky.social+🔥team across @embl.org & @sciencesunige.bsky.social
We finally have a look at what #microtubules are doing during #cellularization in #Sphaeroforma
▶️ tinyurl.com/MTSARC
#ProtistsOnSky

We’re recruiting! Three-year, fully funded #postdoc opportunity: pancreatic cancer #epigenetics & potential new treatments (funded by @ncn.gov.pl & @dfg.de ). Collaboration with @akispapantonis.bsky.social, University of Göttingen (OPUS-LAP). See the ad & contact me! drive.google.com/file/d/1vrFd...

Pls RT‼️ @hanhtkvu.bsky.social lab @embl.org & we @cosheidelberg.bsky.social are looking for a #postdoc to study #regeneration x #autophagy across kingdoms of life.
www.health-life-sciences.de/opportunitie... Pls spread the word & get in touch if you are interested.

Wow, big time preprint drop from @jacobsenucla.bsky.social lab! One of the holy grails of DNA methylation research. Also, the 2-figure paper reminds me of the classic Science Brevia from Simon Chan and Steve showing RNA-directed DNA methylation drives de novo DNAme www.biorxiv.org/content/10.6...

Pleased to share the final version of this behemoth of a paper, now finally published. I guess I can retire now?
www.nature.com/articles/s41...

More functional data, many thousands of words removed, and a few other updates from last year's preprint.

How does the piRNA pathway solve the self vs. non-self problem? 🧬

Since piRNAs come from single-stranded RNA, how does the cell choose the right ones? For years, "piRNA clusters" were seen as THE privileged source. But are they really special and earmarked for biogenesis? (1/19)

The demystification of piRNA clusters

if you wonder how cells generate piRNAs specifically against transposons & you are looking for a weekend read

check out @86dominik.bsky.social's opus magna (or Dominik's great thread)

a shared project with the one and only Rippei Hayashi, lab alumnus & friend

A small polymerase ribozyme that can synthesize itself and its complementary strand The emergence of a chemical system capable of self-replication and evolution is a critical event in the origin of life. RNA polymerase ribozymes can replicate RNA, but their large size and structural ...

Ooooh. Cool new paper on origins of life. A simple 45-nucleotide RNA molecule that can perfectly copy itself.

www.science.org/doi/10.1126/...

New Preprint www.biorxiv.org/content/10.6... from our lab - work by (now) Dr. Feyza Polat Haas with fabulous contributions from many. We show that mammals have a 💪 POWER-Spliceoeome in the 🧠 optimized for metabolic functions. This happens because SNRPB (SmB) is replaced by its paralogue SNRPN (SmN).

Unpopular opinion here (and I’m not even an AI booster, I’m mostly a skeptic), but I think a whole lot of people are overindexed on AI being the too-many-fingers-and-weird-teeth machine and aren’t accepting or even understanding that its output has generally been continuously improving.

See? Science Bluesky has the sauce. Look at all thise posts 🧪

For once an article about the "how to get to Rome" and not "Rome" itself. Collaboration with my "partner-in-crime" @felibas.bsky.social has been a key ingredient of my research over the years. Sara Miller at Molecular Cell spoke with us of how we got there and what we think about collaborations.

Ulrich’s research will help advance our understanding of RNA biology & gene regulation, as well as how these mechanisms might be altered during viral infections & other diseases.
@hohmannulrich.bsky.social comes from the @impvienna.bsky.social / @imbavienna.bsky.social

www.imb.de/about-imb/ne...

Tenure-Track Assistant Professor / Associate Professor in Bioinformatics and/or Computational Biology at Aarhus University, Denmark - Vacancy at Aarhus University Vacancy at Department of Molecular Biology and Genetics - BiRC - Bioinformatics Research Center, Aarhus University

Aarhus University is seeking a Tenure-Track Assistant/Associate Professor in Bioinformatics/Co… https://nat.au.dk/en/about-the-faculty/vacant-positions-and-career/job/tenure-track-assistant-professor-associate-professor-in-bioinformatics-and-or-computational-biology-at-aarhus-university-denmark #job

A near-complete map of human cytosolic degrons and their relevance for disease

We measured degron potency of >200,000 30-residue tiles from >5,000 human proteins, and trained a model to predict degrons from sequence

Led by @vvouts.bsky.social in @rhp-lab.bsky.social

doi.org/10.1126/scia...

The paradox of immune systems conservation between prokaryotes and eukaryotes - Nature Reviews Microbiology The widespread prokaryotic immune systems, in particular restriction–modification, CRISPR–Cas and defensive toxin–antitoxin systems, are absent in eukaryotes, whereas relatively rare ones, such as Arg...

Aude Bernheim @audeber.bsky.social and Eugene Koonin discuss one of most interesting questions in the field connecting bacterial and animal immunity!

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