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1. Phylogeny and divergence time estimation of Io moths and relatives (Lepidoptera: Saturniidae: Automeris )

   https://doi.org/10.7717/peerj.17365  

   Skojec, Chelsea; Earl, Chandra; Couch, Christian D; Masonick, Paul; Kawahara, Akito Y (May 2024, PeerJ)

   Silva, Daniel (Ed.)

   The saturniid moth genusAutomerisincludes 145 described species. Their geographic distribution ranges from the eastern half of North America to as far south as Peru.Automeris moths are cryptically colored, with forewings that resemble dead leaves, and conspicuously colored, elaborate eyespots hidden on their hindwings. Despite their charismatic nature, the evolutionary history and relationships withinAutomerisand between closely related genera, remain poorly understood. In this study, we present the most comprehensive phylogeny ofAutomeristo date, including 80 of the 145 described species. We also incorporate two morphologically similar hemileucine genera,PseudautomerisandLeucanella, as well as a morphologically distinct genus,Molippa. We obtained DNA data from both dry-pinned and ethanol-stored museum specimens and conducted Anchored Hybrid Enrichment (AHE) sequencing to assemble a high-quality dataset for phylogenetic analysis. The resulting phylogeny supportsAutomerisas a paraphyletic genus, withLeucanellaandPseudautomerisnested within, with the most recent common ancestor dating back to 21 mya. This study lays the foundation for future research on various aspects ofAutomerisbiology, including geographical distribution patterns, potential drivers of speciation, and ecological adaptations such as antipredator defense mechanisms. 

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2. The crystal structure of DynF from the dynemicin-biosynthesis pathway of Micromonospora chersina

   https://doi.org/10.1107/s2053230x21012322  

   Kosgei, Abigael J; Miller, Mitchell D; Bhardwaj, Minakshi; Xu, Weijun; Thorson, Jon S; Van_Lanen, Steven G; Phillips, George N (January 2022, Acta Crystallographica Section F Structural Biology Communications)

   Dynemicin is an enediyne natural product fromMicromonospora chersinaATCC53710. Access to the biosynthetic gene cluster of dynemicin has enabled thein vitrostudy of gene products within the cluster to decipher their roles in assembling this unique molecule. This paper reports the crystal structure of DynF, the gene product of one of the genes within the biosynthetic gene cluster of dynemicin. DynF is revealed to be a dimeric eight-stranded β-barrel structure with palmitic acid bound within a cavity. The presence of palmitic acid suggests that DynF may be involved in binding the precursor polyene heptaene, which is central to the synthesis of the ten-membered ring of the enediyne core. 

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3. An elevational shift facilitated the Mesoamerican diversification of Azure‐hooded Jays ( Cyanolyca cucullata ) during the Great American Biotic Interchange

   https://doi.org/10.1002/ece3.10411  

   McCormack, John E.; Hill, Molly M.; DeRaad, Devon A.; Kirsch, Eliza J.; Reckling, Kelsey R.; Mutchler, Marquette J.; Ramirez, Brenda R.; Campbell, Russell M.; Salter, Jessie F.; Pizarro, Alana K.; et al (August 2023, Ecology and Evolution)

   Abstract The Great American Biotic Interchange (GABI) was a key biogeographic event in the history of the Americas. The rising of the Panamanian land bridge ended the isolation of South America and ushered in a period of dispersal, mass extinction, and new community assemblages, which sparked competition, adaptation, and speciation. Diversification across many bird groups, and the elevational zonation of others, ties back to events triggered by the GABI. But the exact timing of these events is still being revealed, with recent studies suggesting a much earlier time window for faunal exchange, perhaps as early as 20 million years ago (Mya). Using a time‐calibrated phylogenetic tree, we show that the jay genusCyanolycais emblematic of bird dispersal trends, with an early, pre‐land bridge dispersal from Mesoamerica to South America 6.3–7.3 Mya, followed by a back‐colonization ofC. cucullatato Mesoamerica 2.3–4.8 Mya, likely after the land bridge was complete. AsCyanolycaspecies came into contact in Mesoamerica, they avoided competition due to a prior shift to lower elevation in the ancestor ofC. cucullata. This shift allowedC. cucullatato integrate itself into the Mesoamerican highland avifauna, which our time‐calibrated phylogeny suggests was already populated by higher‐elevation, congeneric dwarf‐jays (C. argentigula,C. pumilo,C. mirabilis, andC. nanus). The outcome of these events and fortuitous elevational zonation was thatC. cucullatacould continue colonizing new highland areas farther north during the Pleistocene. Resultingly, fourC. cucullatalineages became isolated in allopatric, highland regions from Panama to Mexico, diverging in genetics, morphology, plumage, and vocalizations. At least two of these lineages are best described as species (C. mitrataandC. cucullata). Continued study will further document the influence of the GABI and help clarify how dispersal and vicariance shaped modern‐day species assemblages in the Americas. 

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4. Cell type aware regulatory landscapes governing monoterpene indole alkaloid biosynthesis in the medicinal plant Catharanthus roseus

   https://doi.org/10.1111/nph.20208  

   Li, Chenxin; Colinas, Maite; Wood, Joshua C; Vaillancourt, Brieanne; Hamilton, John P; Jones, Sophia L; Caputi, Lorenzo; O'Connor, Sarah E; Buell, C Robin (January 2025, New Phytologist)

   Summary In plants, the biosynthetic pathways of some specialized metabolites are partitioned into specialized or rare cell types, as exemplified by the monoterpenoid indole alkaloid (MIA) pathway ofCatharanthus roseus(Madagascar Periwinkle), the source of the anticancer compounds vinblastine and vincristine. In the leaf, theC. roseusMIA biosynthetic pathway is partitioned into three cell types with the final known steps of the pathway expressed in the rare cell type termed idioblast. How cell‐type specificity of MIA biosynthesis is achieved is poorly understood.We generated single‐cell multi‐omics data fromC. roseusleaves. Integrating gene expression and chromatin accessibility profiles across single cells, as well as transcription factor (TF)‐binding site profiles, we constructed a cell‐type‐aware gene regulatory network for MIA biosynthesis.We showcased cell‐type‐specific TFs as well as cell‐type‐specificcis‐regulatory elements. Using motif enrichment analysis, co‐expression across cell types, and functional validation approaches, we discovered a novel idioblast‐specific TF (Idioblast MYB1,CrIDM1) that activates expression of late‐stage MIA biosynthetic genes in the idioblast.These analyses not only led to the discovery of the first documented cell‐type‐specific TF that regulates the expression of two idioblast‐specific biosynthetic genes within an idioblast metabolic regulon but also provides insights into cell‐type‐specific metabolic regulation. 

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5. Genetic Diversification in a New Guinean Frog Genus ( Mantophryne , Microhylidae) was Driven by Ancient Tectonic Activity and Climate Reorganisation

   https://doi.org/10.1002/ece3.73291  

   Morris, Rebecca S; Kraus, Fred; Deepak, V; Pal, Saunak; Richards, Stephen J; Maddock, Simon T (May 2026, Ecology and Evolution)

   ABSTRACT Western Melanesia sits at the junction of three major tectonic plates, characterised by dynamic plate interactions and geological diversity. Tectonic activity in this region has given rise to modern New Guinea, a relatively young island with extreme topographic heterogeneity and evolutionarily complex biota. New Guinea—particularly the East Papuan Composite Terrane (EPCT)—supports exceptional frog diversity; however, evolutionary histories of many frogs of the EPCT are poorly understood. The microhylid frog genusMantophrynecurrently includes five described species (M. axanthogaster,M. insignis,M. louisiadensis,M. menziesiandM. lateralis), with the first four confined to small portions of the EPCT and the last distributed across the eastern half of New Guinea. The biogeographic history of these frogs remained incompletely resolved at the time of our study. We estimate thatMantophrynediverged from other microhylid genera approximately 14.4 million years ago (MYA) and began to speciate ca. 8.5 MYA. We recover eight distinct lineages within frogs assigned toM. lateralis, which started to diverge ca. 5.5 MYA. Dispersal ofMantophryneout of the EPCT occurred in the late Pliocene, around the time the Central Highlands expanded eastward to connect with the EPCT. Six pairs of sister lineages arose during a time of significant climate reorganisation in the Late Pliocene—Early Pleistocene when it is possible that areas to the north of the Central Highlands experienced increased precipitation, while areas south of the Central Highlands experienced lower rainfall, resulting in contraction of rainforests and expansion of savannahs. We did not identify any significant differences in habitus between lineages, other thanM. louisiadensiswhich is much larger than all otherMantophryne,and has exceptionally high sexual‐size dimorphism. While an interrogation of the putative cryptic species complex within theM. lateralisclade is beyond the scope of our study, we find that a combination of tectonic rearrangement and climatic history are likely responsible for most of the diversity within the genus that we see today. 

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