Science Shared: August 15

Here's this week’s round up of the most shared items on Bluesky. I've had a screaming alert though my phone from the government telling me not to have any barbecues because of the fire risk, so the most shared paper this week is unfortunately timely. The slightly late publication this week is also connected to the heat. I'm not coping well with it, but that's going to be a common experience for many people in the coming years. Papers behind a paywall are marked 💰otherwise they're free to access at time of checking.

1. Faster, bigger, more severe: Extreme wildfire spread sets the stage for forest ecosystem change in western and boreal North America
Coop, J. D. et al. · Science Advances · 1 post · 99 likes · 49 reposts on Bluesky

Here, we measure daily linear fire growth rates and assess relationships between fire spread, burn severity, and metrics of postfire landscape resilience from 3499 fires occurring between 2012 and 2023 in conifer-dominated forests of Canada and the western US. We find that as linear spread rate increases, so too does fire severity, proportion of area burned at high severity, and distance to surviving live tree seed sources.

2. Tangerine: A new family of Starships from lichen-forming fungi
Tagirdzhanova, G. et al. · Proceedings of the National Academy of Sciences · 1 post · 66 likes · 44 reposts on Bluesky

Recent evidence suggests that lichens may be even more complex than previously appreciated, containing multiple microbial constituents, but how genomes of the principal fungal symbiont (which provides the majority of biomass in lichen tissue) have been shaped during evolution is largely unexplored. Recently, giant transposable elements called Starships have been found in many genomes of filamentous fungi, but to which extent they occur in lichen-forming fungi is not known. In this report, we describe a Starship element from the lichen fungus Xanthoria parietina . This element, named Tangerine , contains several genes that have signatures of horizontal gene transfer from nonlichen-forming fungi, most likely from black yeasts of the Chaetothyriales, that are often lichen-associated.

3. Cell-type-specific activation of broadly perceived effector-triggered immunity restricts pathogen invasion in plants
Chhillar  et al. · Cell Host & Microbe · 2 posts · 70 likes · 22 reposts on Bluesky

Effector-triggered immunity (ETI) is central in plant defense, but whether all cell types execute ETI similarly remains unknown. We combined chemically imposed immune activation with single-cell transcriptomics to profile ETI responses across major leaf cell types in Arabidopsis. Despite uniform ETI perception, we find divergent transcriptional outputs: a core set of defense genes is broadly induced, while distinct cell types activate specialized immune modules.

4. Hemiparasitic Castilleja presence is correlated with increased plant biodiversity across montane plant communities
Argrett, J. C. et al. · American Journal of Botany · 2 posts · 53 likes · 21 reposts on Bluesky

In a 2‐year study at the Rocky Mountain Biological Laboratory, we selected paired presence and absence plots for three species of hemiparasitic Castilleja across seven study sites to explore the association of Castilleja with differences in the structure of montane plant communities.

Anny Chung (鍾彥儀) @yyachung.bsky.social · on Bluesky

New paper by grad student Jordan Argrett on the role of hemiparasitic Castilleja in plant community diversity! He surveyed over 400 plots across multiple sites, spp, and growing seasons. With gorgeous hand-drawn illustrations by an REU coauthor! 🌍🌱🌿
bsapubs.onlinelibrary.wiley.com/doi/10.1002/...

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5. AUXIN RESPONSE FACTORs: from transcription factors to auxin effectors
Dipp‐Álvarez, M., Hernández‐García, J. · New Phytologist · 3 posts · 42 likes · 20 reposts on Bluesky

Signalling pathways have originated and diversified extensively during evolution. Using AUXIN RESPONSE FACTORs (ARFs) as a model, we examine how a plant signalling system evolved through the co‐option of pre‐existing transcriptional regulators, a principle well established in evolutionary biology in organisms, such as animals.

6. Rapid evolution and functional divergence of the monkeyflower Mimulus lewisii telomerase
Samo, N. et al. · bioRxiv · 1 post · 44 likes · 19 reposts on Bluesky

Telomeres are nucleoprotein structures that protect chromosome ends and are maintained by the Telomerase Reverse Transcriptase (TERT) protein that uses a noncoding Telomerase RNA (TR) as a template. In monkeyflowers, Mimulus lewisii had an ancient TR gene duplication, synthesizing an evolutionarily atypical sequence heterogeneous telomere. How TERT interacts with both TR paralogs during telomere maintenance is unknown and answers can shed novel insights underlying telomere function. Using new genome assemblies we discovered TERT is rapidly evolving in lineages sharing the TR duplication. We investigated the functional consequences arising from the rapid evolution, first by using yeast three-hybrid and testing the physical binding between conspecific and heterospecific TERT-TR combinations.

7. Assessing the population genetics of Quercus tardifolia and other red oaks in west Texas
Koontz et al. · International Journal of Plant Sciences · 4 posts · 35 likes · 13 reposts on Bluesky

Here, we describe our research delineating species boundaries in a group of red oaks found in the Chisos and Davis Mountains of west Texas, with a focus on Quercus tardifolia, the lateleaf oak, which was thought to have gone extinct in 2011 before its identification in Big Bend National Park in 2022 and other locations thereafter.

International Journal of Plant Sciences @ijpsjournal.bsky.social · on Bluesky

AOP @ijpsjournal.bsky.social

🚨Undergraduate research🚨

Soft Tissue Preservation of Silicified Melastomataceae Fruits Buried by Intraplate Volcanism in the Early Oligocene Capella Flora, Eastern Australia

Andrew C. Rozefelds et al

www.journals.uchicago.edu/doi/10.1086/...

#PlantScience

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8. Before auxin distribution matters: Prepatterning of the Arabidopsis embryo axis by MPK6-dependent AUX/IAA8 phosphorylation
Bischoff, T. et al. · bioRxiv · 2 posts · 30 likes · 17 reposts on Bluesky

In growth and development of plants, the signaling molecule auxin plays an instrumental role. Many patterning processes are controlled by auxin signaling in a self-organizing matter. After fertilization, such a patterning process needs to be started for the first time during plant life. Contrary to previous models, we show that the first differential auxin response that separates embryonic from extra-embryonic development in the two zygotic daughter cells happens independently of a detectable auxin gradient.

9. Nutrients as signals that spatially organize plant–microbe interactions 💰
Song et al. · Current Opinion in Plant Biology · 1 post · 30 likes · 13 reposts on Bluesky

Here, we bring together current understanding of nutrient-guided plant and microbial responses and highlight emerging technologies that allow their integration. We then introduce a cell-state framework to interpret plant–microbe interactions as emergent properties of spatially coupled cellular responses linked through local chemical environments. This perspective provides a foundation for a more mechanistic and predictive understanding of plant–microbe interactions.

Tatsuya Nobori @tatsuyanobori.bsky.social · on Bluesky

Our new Review is online!

Nutrients can act as spatial signals that organise plant-microbe interactions. We discuss emerging tools and propose a cell-state framework linking plant and microbial cell states through local nutrient landscapes.

sciencedirect.com/science/arti...

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10. Endophytic Flavobacterium promotes root hair development and enhances drought tolerance via an ERF–CEP5 hormonal regulatory module
Rahimi, A. et al. · Nature Plants · 1 post · 12 likes · 13 reposts on Bluesky

Root hairs (RHs) are cellular outgrowths of plant root epidermal cells that are important for water uptake, nutrient acquisition and rhizosphere dynamics. Key genes controlling RH development have been identified, but the regulatory mechanisms of RH growth during drought stress remain largely elusive. Here we show that the bacterial root endophyte Flavobacterium sp. 98 (Flavo98) modulates root system architecture with a pronounced promotion of RH formation and cell elongation that is maintained under low-water conditions.

11. A key role for S-nitrosylation in immune regulation and development in the liverwort Marchantia polymorpha
Tabassum, N., Goodrich, J., Loake, G. J. · Journal of Experimental Botany · 1 post · 18 likes · 8 reposts on Bluesky

Nitric oxide (NO) is an important signalling molecule in flowering plant immunity. It rapidly accumulates in response to pathogen perception. In addition to its direct response to microbes, NO controls a range of defence responses primarily through S-nitrosylation. This process is a redox-dependent modification where a NO group attaches to the thiol of a cysteine residue, creating an S-nitrosothiol (SNO). To explore the role of S-nitrosylation more broadly, we characterized the single-copy S-nitrosoglutathione reductase 1 (MpGSNOR1) gene in the liverwort Marchantia polymorpha, a representative of a lineage widely divergent from flowering plants.

12. Processing and release of the maize phytocytokine Zip1
Koenig et al. (authors unknown) · Plant Physiology · 1 post · 14 likes · 9 reposts on Bluesky

Phytocytokines are endogenous peptides that modulate plant immunity outcomes, yet how their maturation and spatial deployment are controlled remains unclear. Here we show that the maize phytocytokine precursor PROZIP1 is controlled by a spatially separated, 2-stage proteolytic pathway that mechanistically uncouples signal activation from extracellular attenuation.

13. Hydraulic traits govern opposing range shifts of montane trees under warming 💰
Zhang, X. et al. · Nature Climate Change · 1 post · 22 likes · 6 reposts on Bluesky

By integrating hemispheric-scale dendrochronological records from 45 species (121,743 individuals), global observations of elevational range shifts from 102 species and hydraulic trait data for 11 functional attributes, we demonstrate that climate-sensitive species tended to rapidly track warming into higher elevations, whereas taxa resistant to these stresses were poised to have expanded downslope. 

14. A lettuce receptor-like kinase recognizes the highly conserved heptapeptide motif within microbial Nep1-like proteins 💰
Bañales, I. et al. · Proceedings of the National Academy of Sciences · 1 post · 21 likes · 6 reposts on Bluesky

Plants rely on cell surface immune receptors to detect microbial patterns and initiate effective defense responses. Although the Asteraceae family is one of the largest and economically important plant groups, little information is available about its pattern-triggered immunity signaling. Cultivated lettuce ( Lactuca sativa L.) recognizes a 24-amino acid peptide (nlp24) from necrosis- and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs) found in bacteria, fungi, and oomycetes. Here, we perform an extensive characterization of nlp24-induced immune responses in lettuce and identify the LETTUCE nlp24 RECEPTOR (LNR) as the leucine-rich repeat receptor-like kinase mediating its recognition.

15. Chloroplast-encoded small subunit extensions reshape the Chlamydomonas chlororibosome
Waltz, F. et al. · Nature Plants · 1 post · 14 likes · 8 reposts on Bluesky

Chloroplast ribosomes (chlororibosomes) synthesize the core protein components of the photosynthetic apparatus, yet their structural diversity outside flowering plants remains largely unexplored. Here we combine in situ cryo-electron tomography with single-particle cryo-electron microscopy to determine the structure of the chlororibosome from the unicellular green alga Chlamydomonas reinhardtii.

16. Polyploidy: A macromutational force pushing bioeconomic developments
Peeters, M. K. R., Van de Peer, Y. · Proceedings of the National Academy of Sciences · 1 post · 13 likes · 8 reposts on Bluesky

Polyploidization, the consequence of genome doubling, is a macromutation that reshapes genomes, phenotypes, and ecological interactions. Polyploidization often results in novel phenotypes, including alterations in size, physiology, biochemistry, and enhanced stress tolerance. Here, we discuss how strategically leveraging polyploidy can provide significant advancements within the modern bioeconomy committed to reducing our ecological footprint through the sustainable production and use of biological resources.

17. High-resolution microCT reveals relationships between stomata and interior leaf anatomy in sorghum
Fischer, J. M. et al. · Plant Physiology · 1 post · 16 likes · 7 reposts on Bluesky

Stomata are pores in the leaf epidermis that regulate the trade-off between CO2 uptake for photosynthesis and water vapor loss to the atmosphere. Stomatal patterning therefore influences water use efficiency and is a target for engineering to avoid drought stress. However, there is limited understanding of how internal leaf anatomy is coordinated with stomatal development, in part due to the technical challenges of assessing three-dimensional anatomy with sufficient resolution. C4 grasses are understudied, and this is a significant knowledge gap, given their file-like stomatal distribution and unique mesophyll organization. In this study, wild-type sorghum and a low-stomatal density transgenic line expressing a synthetic Epidermal Patterning Factor (EPFsyn) were studied.

18. A specific 296 bp insertion in the DFR1 promoter activates ethylene-mediated anthocyanin biosynthesis during autumn leaf senescence in Quercus aliena 💰
Pei, Z. et al. · Journal of Experimental Botany · 1 post · 21 likes · 5 reposts on Bluesky

Red-leaf ornamental trees are commonly characterized by the enrichment of anthocyanins. Quercus aliena, a dominant native oak species in China, displays striking autumn foliage with yellow to red colors. However, the molecular regulation of anthocyanin biosynthesis during leaf senescence remains largely unknown. In this study, we identified a 296 bp insertion in the promoter of Dihydroflavonol 4-Reductase (DFR1) from the red-leaf Q. aliena cultivar ‘Qiuyun’, which was significantly associated with high anthocyanin accumulation.

19. Oxygen sensing in plants: from dynamic hypoxia signalling to the expanding roles of the Cysteine N-degron pathway
La Monaca, N. et al. · Journal of Experimental Botany · 1 post · 15 likes · 7 reposts on Bluesky

Recent discoveries have fundamentally transformed the paradigm of plant oxygen sensing. Hypoxia is no longer viewed solely because of environmental stress, such as flooding, but as a dynamic, intrinsic physiological signal that actively controls normal plant development.

20. Slow growth as a strategy for plant longevity
Binter, J. et al. · Nature Communications · 1 post · 9 likes · 8 reposts on Bluesky

Ecological theories predict a fundamental trade-off between fast growth and the probability of achieving longevity, with far-reaching consequences for ecosystem resilience and carbon residence time. Tree-ring studies have revealed a globally consistent negative relationship between growth rate and lifespan, yet comparable large-scale evidence for such trade-offs beyond trees remains scarce, largely due to methodological limitations. Here, we exploit annual growth rings formed by secondary thickening in perennial herbaceous plants to test whether the growth–longevity trade-off represents a widespread axis of plant strategies extending across life forms.

Cover image: A firefighter in uniform surveys the aftermath of a forest fire with smoke rising through the trees by IslandHopper X from Pexels.