@trnpl

Resident fly pusher @PMB_Berkeley | Evolutionary geneticist, interested in toxins, insects, microbes | she/her | Midwesterner | Black Lives Matter

 Berkeley, CA
noahwhiteman.org/rebecca-tarnopol.html
Joined August 2019
  • Tweets1.3K
  • Following372
  • Followers497
129Media
Final version out today in @CurrentBiology! Thanks to our excellent reviewers for their helpful suggestions that improved our manuscript: sciencedirect.com/science/ar…
Rebecca Tarnopol@trnpl3 Jun 2024
🧵Excited to share my first author preprint detailing much of my dissertation work! Here we used gene editing to retrace the horizontal transfer of a bacterial gene that now encodes an anti-parasitoid toxin in Drosophila: biorxiv.org/content/10.1101/… /1

Retracing the horizontal transfer of a novel innate immune factor in Drosophila

Immune systems are among the most dynamically evolving traits across the tree of life, and long-lived macroparasites play an outsized role in shaping animal immunity. Even without adaptive immunity,...

biorxiv.org
6
3
19
1,385
Replying to @trnpl @CurrentBiology
You can also find me on the other place now — handle is tarnopol[at]bsky[dot]social !
1
139
Rebecca Tarnopol retweeted
Dan Tracey@Hoosierflyman13 Sep 2024
In 5 of 5 battles, the Velvet Ant survived the attack and we could see its stinger clearly deployed in every case. Everything happens pretty quickly but we actually see that the Mantis releases its grip at the precise moment when the stinger penetrates the forelimb. Nature is 🤯
2
3
3
20
2,949
Rebecca Tarnopol retweeted
nature
@Nature11 Sep 2024
Nature research paper: Drosophila are hosts to the first described parasitoid wasp of adult flies go.nature.com/3MFgETh

Drosophila are hosts to the first described parasitoid wasp of adult flies

Nature - A study reports the discovery of a parasitoid wasp species that uses the adult stage of Drosophila fruit flies as its host.

nature.com
2
53
6
194
99,504
Brat summer is never ending! I’m proud to announce the release of my thesis project on BioRxiv: biorxiv.org/content/10.1101/… In this paper, we unravel the mysterious roles of RickA and Sca2 in cell-to-cell spread and pathogensis during infection with R. parkeri.

The Rickettsia actin-based motility effectors RickA and Sca2 contribute differently to cell-to-cell...

Rickettsia parkeri is an obligate intracellular, tick-borne bacterial pathogen that can cause eschar-associated rickettsiosis in humans. R. parkeri invades host cells, escapes from vacuoles into the...

biorxiv.org
4
7
23
2,137
My very first first-author research article is officially available @ISMEJournal! See what it’s like for a bacterium to live off Chlamy’s photosynthesis under continuous &diurnal light. doi.org/10.1093/ismejo/wrae1…

Scarcity of fixed carbon transfer in a model microbial phototroph–heterotroph interaction

Abstract. Although the green alga Chlamydomonas reinhardtii has long served as a reference organism, few studies have interrogated its role as a primary pr

academic.oup.com
5
9
58
1,928
My first, first author paper is out in @ISMEJournal ! Over the past few years in the @UCBTagaLab we have been learning about how soil bacteria share corrinoids, largely thanks to funding from @DOEScience. Here, we got some answers by studying isolates.🧵 doi.org/10.1093/ismejo/wrae0…

Phylogenetic distribution and experimental characterization of corrinoid production and dependence...

Abstract. Soil microbial communities impact carbon sequestration and release, biogeochemical cycling, and agricultural yields. These global effects rely on

academic.oup.com
8
8
1
30
3,436
Rebecca Tarnopol retweeted
alexa zytnick@zzzytty30 Jul 2024
My first, first author paper is finally out! Here we discover methylolanthanin, a lanthanide chelator secreted by methylotrophs 🧵(1/5) pnas.org/doi/10.1073/pnas.23…

Identification and characterization of a small-molecule metallophore involved in lanthanide...

Many bacteria secrete metallophores, low-molecular-weight organic compounds that bind ions with high selectivity and affinity, in order to access e...

pnas.org
3
12
3
49
5,652
Rebecca Tarnopol retweeted
PLOS Biology@PLOSBiology16 Jul 2024
Ancestral immunity: @EnzoZ_P @AudeBer &co explore the concept of ancestral #immunity - the set of immune modules (domains & proteins) conserved between #prokaryotes & #eukaryotes - including a putative evolutionary scenario for its existence #PLOSBiology plos.io/4cJNLRm
2
71
2
195
59,326
It’s been super fun to see out this project that started from initial ideas I had when I first met with @NKWhiteman in February 2020 to discuss the possibility of joining his lab. I think this study has a little something for everyone, and I've learned a lot in the process! /16
1
4
673
This work would not have been possible without our wonderful collaborators in the @LipinszkiLab and Ando Lab and two wonderful undergraduate mentees Jossie Tamsil and Ji Heon (Jaden) Ha! /17
2
1
4
693
I’m excited to follow up on some of these findings in my last year of my PhD. I’m also looking for postdoc positions in functional evolutionary genetics to start next summer — if you’re hiring, I’d love to chat! 18/18
1
7
2,984
FusionB, a functional nuclease, was secreted into host hemolymph, where it targeted the serosal tissue of developing wasps in both D. ananassae and our D. melanogaster system. This tissue normally helps the wasp gain nutrients from the host and manipulate host physiology. /12
Indirect immunofluorescence images demonstrating localization of Fusion protein to L. boulardi neonate serosal tissue in both D. ananassae and D. melanogaster. The serosal tissue plays a key role in wasp development by sequestering nutrients from the host and modulating host physiology.

ALT Indirect immunofluorescence images demonstrating localization of Fusion protein to L. boulardi neonate serosal tissue in both D. ananassae and D. melanogaster. The serosal tissue plays a key role in wasp development by sequestering nutrients from the host and modulating host physiology.

1
4
497
more replies
Finally, we turned to yeast to dissect which domains were required for Fusion toxicity. We found that both Fusion paralogs induced potent growth defects in yeast through their CdtB domains, but toxicity was contingent on their secretion. /15
Plate scans of yeast showing growth defects when full-length FusionA and FusionB are expressed.

ALT Plate scans of yeast showing growth defects when full-length FusionA and FusionB are expressed.

1
4
469
Regulatory constraint seems to be key. We found constitutive fusionB expression resulted in delayed pupariation followed by death at early pupal stages, providing experimental evidence for hypotheses on the role of gene regulation in promoting prokaryote-to-animal HGT. /14
Photos of pupae constitutively expressing fusionB and control pupae. Flies that express fusionB constitutively die at early pupal stages.

ALT Photos of pupae constitutively expressing fusionB and control pupae. Flies that express fusionB constitutively die at early pupal stages.

1
6
473
To our knowledge this is the first toxic humoral anti-parasitoid factor in Drosophila, where known parasitoid immune defenses are largely cell-mediated. But what prevents this secreted toxin from harming the host? /13
1
3
486
In an experiment I was convinced would not work (!), we found that one of the fusion genes — fusionB — conferred a strong anti-parasitoid phenotype when it was expressed in the same immune tissues where it is expressed in D. ananassae (fat body and hemocytes)! /11
In this experiment, groups of 60 larvae were parasitized by 6 female parasitoid wasps and monitored for development over 30 days. We found that expression of fusionB in the fat bodies and hemocytes of larvae led to ~7X increase in fly survival and ~7X decrease in wasp survival against Leptopilina boulardi wasps, and a ~30% decrease in wasp survival against Leptopilina heterotoma wasps.

ALT In this experiment, groups of 60 larvae were parasitized by 6 female parasitoid wasps and monitored for development over 30 days. We found that expression of fusionB in the fat bodies and hemocytes of larvae led to ~7X increase in fly survival and ~7X decrease in wasp survival against Leptopilina boulardi wasps, and a ~30% decrease in wasp survival against Leptopilina heterotoma wasps.

1
5
509
We focused on Drosophila ananassae, which encodes a standalone full length cdtB homolog and two cdtB::aip56 “fusion” genes. With help from @Bernard_Y_Kim, we found these genes are conserved across almost all sequenced ananassae subgroup species. /7
Phylogeny of the Drosophila shows acquisition events of cdtB and aip56 in the lineage. cdtB is found in the D. biarmipes, Scaptomyza, and D. primaeva lineages, and cdtB and aip56 are found in ananassae subgroup species. The genes are syntenic and highly conserved across ananassae subgroup species.

ALT Phylogeny of the Drosophila shows acquisition events of cdtB and aip56 in the lineage. cdtB is found in the D. biarmipes, Scaptomyza, and D. primaeva lineages, and cdtB and aip56 are found in ananassae subgroup species. The genes are syntenic and highly conserved across ananassae subgroup species.

2
4
456
more replies
To address these questions, we engineered D. melanogaster to express each of the three D. ananassae toxins. Because D. melanogaster does not natively encode these toxins, we could recapitulate the HGT event in a naive drosophilid background. /10
1
4
537
But there were still many questions! Were these toxins directly involved in parasitoid resistance? And if so, how do insects use these toxins to neutralize insect predators without harming themselves? /9
1
3
506
Kirsten (@kirvers) and our fantastic collaborators in the @LipinszkiLab and Ando Lab demonstrated that these genes were expressed in immune tissues and were necessary for D. ananassae to mount its full immune response to parasitoids: pnas.org/doi/full/10.1073/pn… /8

Evolution of insect innate immunity through domestication of bacterial toxins | PNAS

Toxin cargo genes are often horizontally transferred by phages between bacterial species and are known to play an important role in the evolution o...

pnas.org
1
3
438
Load more