Mark A. Hanson

Really cool!

AMP thought of as one-off in Drosophila may have moved around a lot…much like genes encoding antiparasitoid proteins fand pore-forming toxins in insects (see karger.com/jin/article/...). Extremely cool. A challenge is that short peptides present a very hard problem—discerning convergence from HGT…

Immune-microbiome coordination defines interferon setpoints in healthy humans @cellcellpress.bsky.social
www.cell.com/cell/fulltex... @spitzerlab.bsky.social @ucsfhealth.bsky.social @joelbabdor.bsky.social
@pennmedicine.bsky.social

Ig Nobels to move awards to Europe due to concern over US travel visas Scientific awards – which honor research that makes people laugh and then think – to move away from ‘unsafe’ US

🧪 🇨🇭 #IgNobel awards come to Switzerland as US unsafe for scientists
#HoppSchwiiz
www.theguardian.com/science/2026...

Adding #Dros26

Happy International Women’s Day! We are grateful to the incredible women who lead (and have led) the Canadian Society of Ecology and Evolution, & to all the women ecologists & evolutionary biologists across Canada for their important work. You help make our society, country, & planet a better place!

A color photograph of Barbara Liskov, the pioneering American computer scientist, Turing Award winner, and MIT Institute Professor, standing in front of a large black chalkboard filled with dense handwritten mathematical and computer science notations. She is an older woman with short, curly hair, warm smile, and a friendly, engaging expression as she looks directly at the camera. She wears a light mint-green shirt or sweater with a collar. Behind her, the chalkboard is covered in complex equations, diagrams, symbols (including Greek letters like π, arrows, brackets, subscripts, superscripts, terms like "DB", "30sec", "Lop", "D", "T", "eichn", "P", "Joe", "Page", "aps", "uige", and various parentheses, integrals, and code-like fragments), suggesting an active lecture or research discussion on programming languages, data abstraction, or algorithms. The setting appears to be an academic classroom or office at MIT, conveying her enduring role as a mentor and innovator in computer science, particularly for contributions like abstract data types, the Liskov substitution principle, and object-oriented programming foundations. The overall mood is intellectual, approachable, and inspiring.

Computer scientist Barbara Liskov's work forms the foundation of modern software engineering.

She is best known for inventing data abstraction & the Liskov Substitution Principle, concepts that are now fundamental to how almost all modern software is written. #WomenInSTEM #WomensHistoryMonth (1/2)

A warm, color portrait photograph of evolutionary biologist Lynn Margulis seated outdoors next to the textured trunk of a large tree. She is smiling brightly and directly at the camera with a joyful, approachable expression, her eyes sparkling with warmth and intelligence. She has short, curly graying hair, and wears small stud earrings. Her outfit is a patterned blouse or dress in deep purple with floral accents in beige, gold, and brown tones.

Evolutionary biologist Lynn Margulis' groundbreaking work revolutionized our understanding of life's origins and evolution, and how complex life began. She was born #OTD in 1938.

+ Elected, US National Academy of Sciences, 1983
+ National Medal of Science, 1999

#WomenInSTEM #WomensHistoryMonth

Lilian Vaughan Morgan was an incredible #WomenInSTEM that ought to be a household name.

The fly community still uses tools she discovered a century ago. 🪰🤯

Her findings seeded "Bridges' theory" of sex determination by genic balance.🧬❤️

Lilian Vaughan Morgan 👏👏

#InternationalWomensDay #Drosophila

Portrait of Lise Meitner taken in 1928. She is smoking a cigarette and looking impatient to get back to her experiments.

Last week, I mentioned this in passing in a workshop:

In 1938 Enrico Fermi won a Nobel Prize for discovering two new elements of the periodic table.

Lise Meitner shortly showed that Fermi was mistaken and instead had produced known lighter elements by fission.

She did not win a Nobel prize.

A photo of a young Lilian Vaughan Morgan, sitting with a book on her lab staring into the distance.

A photo of an older Lilian Vaughan Morgan, sitting at a lab bench with a microscope and dozens of glass milk bottles bunged with cotton. Lilian is in the middle of applying ether to anaesthetize a bottle of flies.

This #InternationalWomensDay I want to tell the story of Lilian Vaughan Morgan. I learned of Lilian this past year - what a badass.

Lilian was a leading scientist when women weren't welcome in the lab, nor even the department. But she contributed immensely to the genetics of sex determination

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Lilian Vaughan Morgan was an incredible #WomenInSTEM that ought to be a household name.

The fly community still uses tools she discovered a century ago. 🪰🤯

Her findings seeded "Bridges' theory" of sex determination by genic balance.🧬❤️

Lilian Vaughan Morgan 👏👏

#InternationalWomensDay #Drosophila

Very honored to receive this award from GSA! I have immense gratitude for my advisor @nkwhiteman.bsky.social, labmates, collaborators, mentees, and the fly community, who in many ways potentiated my graduate research.

Looking forward to sharing my work at my favorite meeting in my favorite city!

A phylogenetic tree of insects is shown annotating the presence or absence of a an antimicrobial peptide gene across winged insects

Various phylogenetic secondary loss events are mapped to a tree of insects to explain the parsimony calculations necessary to explain the diversity of insect Drosomycin antimicrobial peptide genes

Antimicrobial peptides (AMPs) are key defence molecules of the innate immune system of plants and animals. Understanding the evolutionary origins of AMPs can help to explain how immune systems acquire novelty and vary in their defensive capabilities. However, AMPs evolve rapidly, and so the origins of similar AMPs across organisms is often unclear. Furthermore, false negatives due to low search sensitivity are common and can hinder confident annotations about true absences. Due to these difficulties, understanding whether similar AMP genes found in diverse organisms represent ancestral molecules or evolutionary novelties has been challenging. In this report, we present evidence of horizontal gene transfer (HGT) of the antifungal peptide gene Drosomycin across insects. We show that in Diptera, the presence of Drosomycin is restricted to the Melanogaster group and additionally the distant relative Drosophila busckii. We go on to recover Drosomycin genes in cockroaches (Blattodea), mantises (Mantodea), one katydid (Orthoptera), various beetles (Coleoptera), and a recently acquired pseudogenized Drosomycin locus in Liposcelis booklice (Psocodea), but no other insects. Explaining this diversity through shared ancestry requires at least 50 independent loss events, or just seven HGT events. Previous studies have suggested that similar AMPs found across divergent species reflect conservation from a common ancestor, or due to their small size, that they arose via convergent evolution resulting from pathogen-imposed selection. Our findings suggest horizontal gene transfer can be responsible for the presence of some AMP genes found scattered across the tree of life. By presenting a mechanism through which immune systems can acquire novelty, our study also suggests a possible explanation for certain lineage-specific competencies for defence against infectious disease. While loss of AMP genes is common in certain lineages, here we suggest gain of AMPs can occur just as suddenly.

Pleased to finally share this fun collab that began at #Ento23

@cedricaumont.bsky.social presented & I had seen NCBI annotated some cockroach genomes as "contaminated." Turns out NCBI & I were wrong (much more fun).

Horizontal transfer of an #AntimicrobialPeptide across insects
bit.ly/DrsHGT

1/🧵

I'm sorry, 50 what now?

"We present a GPU implementation of kallisto for RNA-seq transcript quantification (...). For a large dataset of 295 million reads, runtime drops from 40 minutes to 50 seconds"

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

This helped me find this post. So thanks!

Great initiative! We've been thinking to set up something similar here in the UK/Europe. Will sign up shortly.

Quick plug for our new resource, the Drosophila Species Stock Exchange. This is a database and mailing list that documents species currently in culture and the labs holding them. If you want to know more or sign up then please get in touch. See attached for more info and please share!

ExE 2026

Interested in the interface of evolution 🧬 and ecology 🌳? Then you cannot miss #ExE2026! Hosted by @uniexecec.bsky.social in beautiful #Cornwall, this #conference has a stellar line-up of speakers and lots of pre-and post-conference workshops. Space is limited, so register now at evoxeco.uk!

We have D. buzzati and some related species. Feel free to email mark.hanson.(at].exeter.ac.uk :)

Thank you! Glad to hear!

p.s. @ripplingideas.bsky.social: been experimenting with the last 3 papers I've preprinted to actually typeset them manually (in Word, not as painful as you might think). First one ~1h to figure things out, but now that I've got a 'template' of sorts, it's <30m.

#PreprintLikeYouWantPeopleToReadIt

Finally, some hashtags

#Drosophila #EcoEvo #InsectImmunity #AMP #AMPs #Evolution #JumpingGenes #IDsky #AcademicSky #ImmunoSky #SymbioSky #MicroSky #Genetics

Thanks to @cedricaumont.bsky.social and Dino McMahon for putting up with me for >2 years as we sorted this all out. also thanks to @blongdon.bsky.social and the @royentsoc.bsky.social #Ento23 organisers for hosting the meeting that kicked of this collaboration! Also to PhyloPic for the silhouettes ❤️

First page of the PDF. We even formatted it nicely so you could pick it up and read it like it was a mature piece of reasearch - because it is. This is something I'm experimenting with in my group to boost the utility of preprints.

AMPs can be duplicated, and they evolve rapidly. AMP genes can also be lost over time, perhaps due to selection imposed by host ecology-relevant 🦠.

Here we suggest gain of tried-and-tested AMPs can occur just as suddenly; a mechanism to generate lineage-specific defence competence.

8/8

A diagram showing Drosomycin loss in wood-feeding cockroaches and termites

Lastly, we also observed that Drosomycin is secondarily lost in some lineages.

The clearest case is of wood-feeding cockroaches and termites relative to cockroach/mantis outgroup – a loss associated with dietary shift akin to our previous finding in flies (Hanson et al., 2023; Science).

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Drosomycin is found in the distance lineage of Drosophila busckii on different chromosomes from where it is found in D. melanogaster. The loci do not share ancestry, as neighbour genes do not overlap. Two copies of D. busckii Drs are immune induced.

The diversity of Drosomycin mature peptide sequences. The signal peptide is poorly conserved (and more similar between mantises and beetles than beetles and flies). 85-90% similarity across insect Drs residues in the mature peptide domain. But there are some key sites with widespread polymorphisms, and also some fixed Serine residues that let us do codon analyses investigating whether these sequences arose via convergent evolution or orthologous sequence.

TLDR: we characterise multiple Drs loci & sequences. In at least one seeming HGT event, Drs genes are even immune-induced. We also found 4 conserved serine codons that let us check if any gene lineages could be convergent evolution[3]. 0/4 on convergence!

3. www.pnas.org/doi/10.1073/...

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Drosomycin is found in mantises, cockroaches, two lineages of beetles, a single katydid, a pseudogene in booklice, and an independent long branch of Drosophila

Here we present a case of similar AMPs scattered across multiple insect orders being explained by horizontal gene transfer. The #Drosophila antifungal peptide Drosomycin was thought to be restricted to D. melanogaster and friends. It's not. It's really not.

Immune novelty emerging via HGT❕

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Structural basis for translation inhibition by the glycosylated drosocin peptide - Nature Chemical Biology Koller et al. determined structures of the O-glycosylated antimicrobial peptide drosocin from Drosophila melanogaster in complex with the bacterial ribosome, revealing the mechanism by which drosocin ...

Convergent evolution of DptB occurred in fruit flies separated by >100ma[1]. Many P-rich peptides look the same across dolphins, firebugs, or flies[2]. When are similar AMPs convergent vs shared ancestry?

1. www.science.org/doi/10.1126/...
2. www.nature.com/articles/s41...

or... door #3?

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AMP genes are also super rapidly evolving. Immune genes tend to evolve faster than 99% of the genome, but AMPs are even more confusing as they are short & often fail to be annotated. They also duplicate, & copies or even gene families can be lost.

That's made it puzzling to study AMP evolution

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