Author: slquinlan

Commun Psychol. 2025 Oct 7;3(1):145. doi: 10.1038/s44271-025-00324-4.

ABSTRACT

Every social situation that people encounter in their daily lives comes with a set of unwritten rules about what behavior is considered appropriate or inappropriate. These everyday norms can vary across societies: some societies may have more permissive norms in general or for certain behaviors, or for certain behaviors in specific situations. In a preregistered survey of 25,422 participants across 90 societies, we map societal differences in 150 everyday norms and show that they can be explained by how societies prioritize individualizing moral foundations such as care and liberty versus binding moral foundations such as purity. Specifically, societies with more individualistic morality tend to have more permissive norms in general (greater liberty) and especially for behaviors deemed vulgar (less purity), but they exhibit less permissive norms for behaviors perceived to have negative consequences in specific situations (greater care). By comparing our data with available data collected twenty years ago, we find a global pattern of change toward more permissive norms overall but less permissive norms for the most vulgar and inconsiderate behaviors. This study explains how social norms vary across behaviors, situations, societies, and time.

PMID:41057696 | DOI:10.1038/s44271-025-00324-4

Nat Plants. 2025 Oct 3. doi: 10.1038/s41477-025-02122-6. Online ahead of print.

ABSTRACT

Iridoids are specialized monoterpenes ancestral to asterid flowering plants^1,2 that play key roles in defence and are also essential precursors for pharmacologically important alkaloids^3,4. The biosynthesis of all iridoids involves the cyclization of the reactive biosynthetic intermediate 8-oxocitronellyl enol. Here, using a variety of approaches including single-nuclei sequencing, we report the discovery of iridoid cyclases from a phylogenetically broad sample of asterid species that synthesize iridoids. We show that these enzymes catalyse formation of 7S-cis-trans and 7R-cis-cis nepetalactol, the two major iridoid stereoisomers found in plants. Our work uncovers a key missing step in the otherwise well-characterized early iridoid biosynthesis pathway in asterids. This discovery unlocks the possibility to generate previously inaccessible iridoid stereoisomers, which will enable metabolic engineering for the sustainable production of valuable iridoid and iridoid-derived compounds.

PMID:41044409 | DOI:10.1038/s41477-025-02122-6

Front Plant Sci. 2025 Sep 16;16:1657140. doi: 10.3389/fpls.2025.1657140. eCollection 2025.

ABSTRACT

In reciprocal interspecific near-isogenic lines developed by crossing elite cultivars Acala Maxxa (Gossypium hirsutum) and Pima S6 (G. barbadense) representing the two major domesticated species of cotton, we identified genomic locations underpinning an important fiber quality trait – fiber elongation (ELO). Phenotypic evaluation of these lines in three environments revealed a total of 36 QTLs, including 14 (38.89%) on the D subgenome, from a progenitor that does not produce spinnable fiber. Nearly half (16, 44.4%) of the 36 QTLs identified in the study explained less than 6% of phenotypic variation, and two (EL07.1 and EL25.1) were new, justifying the use of near-isogenic lines for analysis. Significantly larger additive effects of these QTLs in comparison to those reported using early generation backcrosses, F₂ and F₂ derived populations as well as recombinant inbred lines (RILs) show that NILs offer an advantage in estimating more precise QTL effects by removing background noise due to segregating genomic regions. Seven genomic regions on chromosomes 2, 6, 9, 12, 15 and 18 were consistently associated with ELO in two of the three environments tested. A total of 11 (30.56% of) QTLs had transgressive allele effects, i.e. which were opposite of what would be predicted from the parental phenotypes, indicating opportunities to breed superior interspecific lines; and three QTLs (8.33%) had heterotic alleles that may contribute to the striking fiber quality of F₁ hybrids between these species. Limited reciprocity of QTLs in the two backgrounds is attributed to the combined consequences of epistasis, small phenotypic effects and imperfect coverage of donor chromatin in the recipient background. The availability of DNA markers linked to both G. barbadense and G. hirsutum QTLs identified in this and other studies promise to assist breeders in transferring and maintaining valuable traits from exotic sources during cultivar development.

PMID:41036399 | PMC:PMC12479486 | DOI:10.3389/fpls.2025.1657140

mBio. 2025 Sep 30:e0150525. doi: 10.1128/mbio.01505-25. Online ahead of print.

ABSTRACT

In most branches of the fungal kingdom, sexual development marks a dramatic shift from simple multicellular hyphae to complex fruiting bodies composed of multiple tissues and cell types. It is essential to tightly regulate development to prevent unnecessary energy investment into building these structures. Polycomb repressive complex 2 (PRC2) is a highly conserved regulator of development in multicellular organisms. In plants, animals, and some fungi, PRC2 tri-methylates histone H3 lysine 27 in promoters and gene bodies to repress gene expression. In Neurospora crassa, H3K27me3-associated genes are poorly conserved and stably repressed in standard lab conditions. Through analysis of publicly available RNA-seq experiments, we found that PRC2-methylated genes are specifically activated during sexual development. PRC2-methylated genes comprise a distinct subset of developmentally induced genes (DIGs) characterized by an exceptionally high degree of cell-type specificity. Loss of PRC2 activity results in the precocious formation of perithecia-like structures (dubbed false perithecia), even in the absence of a compatible mating-type partner. These structures show a unique gene expression profile with the activation of both PRC2-methylated and unmethylated DIGs, suggesting that loss of PRC2 leads to a major transcriptional reprogramming event. Together, these data suggest that PRC2 is part of a developmental checkpoint that restricts fruiting body development to the appropriate conditions.IMPORTANCEDevelopment of multicellular eukaryotes involves transcriptional reprogramming to drive cell fate transitions. This study identified PRC2 as a critical regulator of cell fate in the model filamentous fungus Neurospora crassa, where it silences a subset of sexual development genes. Loss of regulation by PRC2 triggers a major reprogramming event in which genes specifying sexual tissues cannot be repressed, causing a homeotic transition. These results provide novel insights into the role of PRC2-mediated regulation in the fungal kingdom and uncover a critical checkpoint regulating complex multicellular development.

PMID:41025791 | DOI:10.1128/mbio.01505-25

Proc Natl Acad Sci U S A. 2025 Oct 7;122(40):e2503876122. doi: 10.1073/pnas.2503876122. Epub 2025 Sep 29.

ABSTRACT

Polycomb group (PcG) proteins form chromatin modifying complexes that stably repress lineage- or context-specific genes in animals, plants, and some fungi. Polycomb Repressive Complex 2 (PRC2) catalyzes trimethylation of lysine 27 on histone H3 (H3K27me3) to assemble repressive chromatin. In the model fungus Neurospora crassa, H3K27me3 deposition is regulated by the H3K36 methyltransferase ASH1 and components of constitutive heterochromatin including the H3K9me3-binding protein HETEROCHROMATIN PROTEIN 1 (HP1). Hypoacetylated histones are a defining feature of both constitutive heterochromatin and PcG-repressed chromatin, but how histone deacetylases (HDACs) contribute to normal H3K27me3 and transcriptional repression within PcG-repressed chromatin is poorly understood. We performed a genetic screen to identify HDACs required for repression of PRC2-methylated genes. In the absence of HISTONE DEACETYLASE-1 (HDA-1), PRC2-methylated genes were activated and H3K27me3 was depleted from typical PRC2-targeted regions. At constitutive heterochromatin, HDA-1 deficient cells displayed reduced H3K9me3, hyperacetylation, and aberrant enrichment of H3K27me3 and H3K36me3. CHROMODOMAIN PROTEIN-2 (CDP-2) is required to target HDA-1 to constitutive heterochromatin and is also required for normal H3K27me3 patterns. Patterns of aberrant H3K27me3 were distinct in isogenic ∆hda-1 strains, suggesting that loss of HDA-1 causes stochastic or progressive epigenome dysfunction. To test this, we constructed a new Δhda-1 strain and performed a laboratory “aging” experiment. Deletion of hda-1 led to progressive epigenome decay over hundreds of nuclear divisions. Together, our data indicate that HDA-1 is a critical regulator of epigenome stability in N. crassa.

PMID:41021810 | DOI:10.1073/pnas.2503876122

Theor Appl Genet. 2025 Sep 27;138(10):260. doi: 10.1007/s00122-025-05043-2.

ABSTRACT

Exotic Gossypium accessions still harbor QTL‑validated alleles that, combined with CRISPR pyramiding and genomic selection, can break the entrenched fiber length-strength trade‑off. Cotton’s four independent domestications twice in diploids and twice in allotetraploids offer a natural experiment in fiber improvement. Synthesizing three decades of data, we chart how polyploidy, selection and modern breeding have repeatedly reshaped the Gossypium genome. More than 15,000 quantitative trait locus (QTL) and genome wide association mapping studies (GWAS) hits converge on a handful of chromosomal “hotspots”; new MAGIC, NAM, NIL and long-read resources now narrow these peaks to < 200 kb, resolving causal genes such as GhHOX3, GhZF14 and GhMYB7. Multi-omics evidence links auxin, ethylene, gibberellin, brassinosteroid and strigolactone signaling to HDZIP IV, MYB, bHLH/HLH and ERF networks that drive fiber initiation, extreme cell elongation and cellulose deposition. Population genomics shows that ~ 40% of favorable fiber alleles are fixed in elite Gossypium hirsutum, yet wild diploids and landraces still harbor variants that could break the length strength trade-off. We propose a three-step roadmap genomic selection, CRISPR gene pyramiding and accelerated introgression to expand cotton’s genetic base and deliver fibers suited to sustainable textile demands.

PMID:41014362 | DOI:10.1007/s00122-025-05043-2

Plant Cell Physiol. 2025 Sep 26:pcaf122. doi: 10.1093/pcp/pcaf122. Online ahead of print.

ABSTRACT

Plant cell wall polysaccharide glycosyltransferases catalyze the transfer of sugars from specific nucleotide sugar donors onto specific acceptor substrates. The mechanisms of how their enzymatic specificity is determined is one of the long-standing questions in plant cell wall biology. In this report, we studied the biochemical functions of Arabidopsis and poplar GT61 glycosyltransferases involved in xylan substitutions and investigated the molecular determinants of their nucleotide sugar donor specificity. Enzymatic activity assays of recombinant proteins of Arabidopsis and poplar GT61 members demonstrated that two of them, AtX2AT1 and PtrX2AT1, exhibited xylan 2-O-arabinosyltransferase activities specifically using UDP-Araf, two other ones, AtXYXT2/3, possessed xylan 2-O-xylosyltransferase activities specifically using UDP-Xyl, and three other ones, PtrXXAT1/2/3, were able to catalyze the transfer of 2-O-Araf and 2-O-Xyl onto xylan using both UDP-Araf and UDP-Xyl. Structural modeling and molecular docking of PtrXXAT1 identified amino acid residues involved in interacting with UDP-Araf and UDP-Xyl at the putative active site and site-directed mutagenesis revealed their critical roles in PtrXXAT1 catalytic activities. Furthermore, structural alignment and reciprocal swapping of UDP-Xyl-interacting residues of PtrXXAT1 with their corresponding residues of AtX2AT1 pinpointed key residues determining their nucleotide sugar donor specificity. Our results indicate that Arabidopsis and poplar GT61 members catalyze 2-O-Araf- and/or 2-O-Xyl substitutions of xylan and that subtle structural differences in their substrate-binding pockets could alter their substrate specificity toward nucleotide sugar donors.

PMID:41001967 | DOI:10.1093/pcp/pcaf122

Fungal Genet Biol. 2025 Sep 23:104038. doi: 10.1016/j.fgb.2025.104038. Online ahead of print.

ABSTRACT

Nitrous oxide (N₂O) derived from agricultural activity is a major contributor to Earth’s greenhouse effect. Synthetic nitrogen fertilizer applied at high levels, particularly combined with heavy rainfall events, generates hot spots of N₂O emissions in agricultural fields due to the process of microbial denitrification. Here, a key conserved fungal denitrification enzyme necessary for N₂O emissions was identified. Phylogenetic analysis revealed that fungal NOR1-like genes, with rare exceptions, are highly conserved and confined to the phylum Ascomycota. Plant pathogenic Fusarium species that possess NOR1 exhibited drastic differences in N₂O production based on denitrification potential. Functional characterization of the p450nor nitric oxide reductase encoding gene, NOR1, in the soil-borne denitrifying maize pathogen, Fusarium verticillioides, showed that this enzyme is critical for fungal N₂O production. Deletion of the single copy NOR1 gene in F. verticillioides eliminated N₂O emissions. Complementation of deletion mutants via the NOR1 gene add-back restored wild type N₂O emission levels and segregation analysis further corroborated the pivotal role of NOR1 for N₂O emissions. We suggest targeting of the NOR1 enzyme as an effective strategy to reduce fungal-based N₂O emissions.

PMID:40998212 | DOI:10.1016/j.fgb.2025.104038

Plant J. 2025 Sep;123(6):e70498. doi: 10.1111/tpj.70498.

ABSTRACT

The apoplast is a critical interface in plant-pathogen interactions, particularly in the context of pattern-triggered immunity (PTI), which is initiated by recognition of microbe-associated molecular patterns. Our study characterizes the proteomic profile of the Arabidopsis apoplast during PTI induced by flg22, a 22-amino-acid bacterial flagellin epitope, to elucidate the output of PTI. Apoplastic washing fluid was extracted with minimal cytoplasmic contamination for liquid chromatography-tandem mass spectrometry analysis. By comparing our data to publicly available transcriptome profiles of flg22 treatment from 1 to 18 h, we observed that several highly abundant proteins exhibit relatively unchanged gene expression across all time points. We also observed topological bias in peptide recovery of 19 enriched receptor-like kinases with peptides predominantly recovered from their ectodomains. Notably, tetraspanin 8, an exosome marker, was enriched in PTI samples. We additionally confirmed increased concentrations of exosomes during PTI. This study enhances our understanding of the proteomic changes in the apoplast during plant immune responses and lays the groundwork for future investigations into the molecular mechanisms of plant defense under recognition of pathogen molecular patterns.

PMID:40991770 | DOI:10.1111/tpj.70498

Phytopathology. 2025 Sep 23. doi: 10.1094/PHYTO-05-25-0178-R. Online ahead of print.

ABSTRACT

Pantoea stewartii subspecies indologenes (Psi) isolates can cause disease in several Poaceae hosts, including millets and rice and were recently known to cause foliar and bulb symptoms characteristic of center rot in onions. Cover crops such as millet and cash crops like corn are commonly grown in the summer after onion harvest in Vidalia, Georgia, USA. However, the risk of pathogen transmission to onions in the cropping systems where summer crops precede onion planting is largely understudied. We evaluated the survivability of Psi in corn and pearl millet residues and assessed its ability to colonize onions transplanted into the infested soil. Our microplot study showed that millet and corn residues support the transient survival of Psi. The presence of the pathogen in the soil also overlapped with the presence of onion transplants. However, despite planting onion seedlings in Psi-infested soil, no bacterial colonization was observed in their rhizosphere and foliar surfaces. We further investigated genetic determinants for bacterial survival in millet residue and bare soil by creating deletion mutants of the genes responsible for exopolysaccharides, flagellar motility, quorum sensing and pathogenicity in a Psi pathovar cepacicola strain PNA 14-12. All mutant strains persisted for at least 24 days in millet residue at high population levels and colonies of all the strains remained detectable in bare soil until 44 days. Overall, our findings suggest that the risk of Psi transmission from millet or corn residue to onions appears is considerably low.

PMID:40986336 | DOI:10.1094/PHYTO-05-25-0178-R