Fibroblast growth factors (FGFs) are crucial for various cellular functions, including proliferation, differentiation, tissue repair, and immune responses. FGF10, part of the FGF7 subfamily, binds to the FGFR2b receptor via heparin sulfate. We determined the crystal structure of human FGF10 alone. In the FGFR2b-bound form, the N-terminal region of FGF10 formed an α1 helix. This α1 helix, however, exists as a flexible loop with dual conformations in the unbound structure. Deleting this conformationally dynamic α1 helix reduces cell proliferation activity in vitro. Receptor-binding-induced formation of the α1 helix in FGF10 creates a distinct protruded knob and concave pocket on the globular core of FGFs, increasing the FGFR2b-binding surface by 37%. Size-exclusion chromatography showed a concentration-dependent dimer-monomer shift in purified FGF10, with the hydrophobic dimer interface aligning with the FGFR2b D2-domain-binding surface. These findings suggest that the conformational change in the N-terminal region and the dimer-monomer shift are critical for FGF10's specific binding to FGFR2b, highlighting the functional significance of these structural adaptations.

A plant species has historically experienced repeated cycles of habitat connectivity and isolation, which have played a crucial role in increasing genetic diversity and promoting long-term survival. Therefore, understanding these dynamics is essential for developing effective conservation strategies. Thuja koraiensis is an endangered coniferous shrub inhabiting the mountain summits of the Baekdudaegan, a critical ecological axis in northeastern Asia. We used a genome dataset (242 SNPs) generated by the MIG-seq (Multiplexed ISSR Genotyping by Sequencing) method to evaluate the genetic diversity and structure of T. koraiensis populations across their entire distribution range. T. koraiensis exhibited a population history, with range expansion during glacial periods and contraction during interglacial periods. During the Last Glacial Maximum (LGM), genetic connectivity among populations was high, but post-LGM habitat fragmentation led to increasing isolation. This shift resulted in a rapid decline in effective population size and severe bottlenecks across all populations. Consequently, the genetic variation in current populations exhibits a geographically random pattern. Nevertheless, no signs of inbreeding or significant imbalances in genetic diversity were detected among populations. Therefore, we propose that conservation strategies should not solely focus on increasing genetic diversity or enhancing gene flow among populations but rather reflect the species’ historical demographic dynamics and aim to conserve the unique genetic characteristics of each population.

Fibroblast growth factors (FGFs) are crucial for various cellular functions, including proliferation, differentiation, tissue repair, and immune responses. FGF10, part of the FGF7 subfamily, binds to the FGFR2b receptor via heparin sulfate. We determined the crystal structure of human FGF10 alone. In the FGFR2b-bound form, the N-terminal region of FGF10 formed an α1 helix. This α1 helix, however, exists as a flexible loop with dual conformations in the unbound structure. Deleting this conformationally dynamic α1 helix reduces cell proliferation activity in vitro. Receptor-binding-induced formation of the α1 helix in FGF10 creates a distinct protruded knob and concave pocket on the globular core of FGFs, increasing the FGFR2b-binding surface by 37%. Size-exclusion chromatography showed a concentration-dependent dimer-monomer shift in purified FGF10, with the hydrophobic dimer interface aligning with the FGFR2b D2-domain-binding surface. These findings suggest that the conformational change in the N-terminal region and the dimer-monomer shift are critical for FGF10's specific binding to FGFR2b, highlighting the functional significance of these structural adaptations.

A plant species has historically experienced repeated cycles of habitat connectivity and isolation, which have played a crucial role in increasing genetic diversity and promoting long-term survival. Therefore, understanding these dynamics is essential for developing effective conservation strategies. Thuja koraiensis is an endangered coniferous shrub inhabiting the mountain summits of the Baekdudaegan, a critical ecological axis in northeastern Asia. We used a genome dataset (242 SNPs) generated by the MIG-seq (Multiplexed ISSR Genotyping by Sequencing) method to evaluate the genetic diversity and structure of T. koraiensis populations across their entire distribution range. T. koraiensis exhibited a population history, with range expansion during glacial periods and contraction during interglacial periods. During the Last Glacial Maximum (LGM), genetic connectivity among populations was high, but post-LGM habitat fragmentation led to increasing isolation. This shift resulted in a rapid decline in effective population size and severe bottlenecks across all populations. Consequently, the genetic variation in current populations exhibits a geographically random pattern. Nevertheless, no signs of inbreeding or significant imbalances in genetic diversity were detected among populations. Therefore, we propose that conservation strategies should not solely focus on increasing genetic diversity or enhancing gene flow among populations but rather reflect the species’ historical demographic dynamics and aim to conserve the unique genetic characteristics of each population.

Our results suggest that the selfing-associated morphological changes in D. kiusiana are of relatively old origin (at least 100 000 years ago) and were driven by directional selection for efficient self-pollination. We provide evidence that the evolution of the selfing syndrome in D. kiusiana is not strongly associated with a severe population bottleneck.

Abstract Rare plant species identified in project areas where land is to be developed or altered may need to be extracted for ex situ conservation under human control. During ex situ conservation, it is important to minimize the impact of adverse factors including the potentially limited environmental adaptability of rare plants under cultivation and possible losses of genetic diversity due to inbreeding if the number of conserved individuals is low. Here we evaluate the conservation difficulty and genetic diversity of populations of the rare plant Violα raddeana at five sites based on harmful gene accumulation and gene duplication data gathered using RNA‐seq. Additionally, we evaluate the genetic diversity and structure of these populations using single‐nucleotide polymorphism (SNP) data acquired by multiplexed inter‐simple sequence repeat genotyping by sequencing (MIG‐seq). The results obtained indicate that the V. raddeana populations have declined but remain robust toward environmental changes and can undergo voluntary mating at all sites. Moreover, we observed clear genetic differentiation between two populations in close geographic proximity. We considered that if the majority of the remaining individuals of V. raddeana in each genetically related population were transplanted and cultivated, it would be possible to maintain their genetic diversity through ex situ conservation. It is important that V. raddeana be kept under ex situ conservation management. In order to achieve this, we should work with public organizations such as local government agencies and botanical gardens.

Abstract Hepatica insularis, a warm-temperate endemic confined to the southwestern coastal region and Jeju Island of Korea, has long posed a taxonomic challenge in relation to Hepatica asiatica, which is more broadly distributed across cool-temperate regions of northeastern Asia. To address this issue, we investigated their phylogeographical history. Genetic analyses were conducted using eight nuclear microsatellite loci and three non-coding regions of plastid DNA, based on 294 individuals sampled from 13 populations across the Korean Peninsula. Analyses of nuclear markers revealed two distinct genetic clusters concordant with geographical distribution, whereas plastid variation revealed a contrasting signal suggestive of incomplete lineage sorting (ILS). Our demographic analyses estimated that H. insularis and H. asiatica diverged approximately 17 200 years ago around the Last Glacial Maximum (LGM). The current nuclear structure probably reflects historical separation of humid coastal refugia situated along the palaeo-coastlines of the Korean Peninsula and the exposed East China Sea shelf during the LGM. Given the recency of divergence, which has resulted in ILS, we propose that these taxa do not represent distinct species, but instead reflect population-level divergence within a single species. This study sheds light on how rapid evolutionary radiation unfolds in Hepatica species and its implications for their taxonomic interpretation.

This study defined alpine and subalpine zones in South Korea based on the natural environment, plant distribution patterns, and references to domestic and international literature. Alpine and subalpine plants were classified using five criteria, including their distribution in alpine zones and their global distribution range, focusing on the species listed in the national species list. The alpine zone lies above the tree line and is dominated by tundra vegetation, including shrubs, herbs, and lichens. A gradual reduction in tree height and density with increasing elevation and shrubs, krummholz, dwarf krummholz, and tree islands characterized the subalpine zone. The Korean Peninsula native alpine and subalpine plants were classified into 195 taxa comprising 43 families, 113 genera, 167 species, 3 subspecies, and 25 varieties. Notably, Ericaceae and Asteraceae accounted for the highest proportions, with 20 taxa each. The life forms were divided into 35 woody and 160 herbaceous taxa. In total, 72 taxa of alpine and subalpine plants have been identified in South Korea. Most were isolated from the high-altitude summit areas and ridges of Mt. Halla, Mt. Jiri, and Mt. Seorak. However, alpine plants are likely affected by climatic and environmental changes, potentially leading to a decline in population and species.

Daphne pseudomezereum var. koreana has traditionally been treated as a variety of D. pseudomezereum, a species endemic to the warm-temperate regions of Japan. However, var. koreana occurs primarily in cool-temperate regions of northeastern Asia— including the Baekdudaegan Mountain Range in Korea, southern Manchuria, southern Primorsky Krai, Sakhalin, and Hokkaido—and thus exhibits distinct ecological and biogeographic characteristics from var. pseudomezereum. To reassess its taxonomic position, we conducted molecular phylogenetic analyses using complete chloroplast genome and nuclear ribosomal ITS sequences. Plastome phylogeny supports var. koreana as a sister to D. kamtschatica, whereas nuclear ribosomal internal transcribed spacer phylogeny places it as a sister to var. pseudomezereum. While the phylogenetic discordance complicates its placement, we interpret this discordance as in itself ultimately revealing var. koreana as a lineage bearing an evolutionary identity possibly shaped by ancient hybridization. Evidence from ecology, biogeography, life-history (presence of well-developed rhizomes), and morphology (e.g., growth habit, calyx coloration, anther position) further supports its affinity with D. kamtschatica. Taken together, we propose reclassifying var. koreana as a variety of D. kamtschatica, representing a geographically disjunct southwestern lineage separated from var. kamtschatica by the Sea of Okhotsk. Plants occurring in southern Japan currently considered to be var. koreana may instead represent distinct, undescribed taxa.

Hepatica insularis Nakai, a perennial herb endemic to warm-temperate regions on the Korean Peninsula, has been a subject of taxonomic debate due to its morphological similarities with Hepatica asiatica Nakai. To address the taxonomic ambiguity and provide evolutionary insights into H. insularis, we developed 15 polymorphic microsatellite markers. Of these, eight markers were successfully cross-amplified in H. asiatica, demonstrating their broader applicability. The markers exhibited high levels of polymorphism, with the number of alleles per locus ranging from two to eleven. The expected heterozygosity (H<sub>E</sub>) and observed heterozygosity (H<sub>O</sub>) values ranged from 0.180 to 0.802 and from 0.000 to 0.933, respectively. The developed markers will serve as a valuable tool for future phylogeographic studies aiming to understand the genetic structure and diversity of H. insularis and related taxa.

<i>Quercus turbinella</i> (section <i>Quercus</i>; Fagaceae) is an evergreen shrub characteristic in central Arizona and it concerns one of the most abundant and economically important genera of <i>Quercus</i> in the Northern Hemisphere. Here, we have sequenced the complete chloroplast genome to provide insight into the phylogenetic relationship of <i>Q. turbinella</i>. The whole genome is 161,208 bp in length with two inverted repeat regions of 25,827 bp each, which separate a large single-copy region of 90,552 bp and a small single-copy region of 19,002 bp. A total of 136 genes were annotated, including 88 protein-coding genes, eight ribosomal RNAs, and 40 transfer RNAs. The result of the maximum-likelihood phylogenetic analysis strongly suggested that <i>Quercus turbinella</i> had a close relationship to <i>Quercus macrocarpa</i> with strong bootstrap support.