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Basic helix–loop–helix (bHLH) proteins, one of the most important and largest transcription factor family in plants, play important roles in regulating growth and development, stress response. In recent years, many bHLH family genes have been identified and characterized in woody plants. However, a systematic analysis of the bHLH gene family has not been reported in Ginkgo biloba , the oldest relic plant species. In this study, we identifed a total of 85 GbbHLH genes from the genomic and transcriptomic databases of G. biloba , which were classified into 17 subfamilies based on the phylogenetic analysis. Gene structures analysis indicated that the number of exon–intron range in GbbHLHs from 0 to 12. The MEME analysis showed that two conserved motifs, motif 1 and motif 2, distributed in most GbbHLH protein. Subcellular localization analysis exhibited that most GbbHLHs located in nucleus and a few GbbHLHs were distributed in chloroplast, plasma membrane and peroxisome. Promoter cis-element analysis revealed that most of the GbbHLH genes contained abundant cis-elements that involved in plant growth and development, secondary metabolism biosynthesis, various abiotic stresses response. In addition, correlation analysis between gene expression and flavonoid content screened seven candidate GbbHLH genes involved in flavonoid biosynthesis, providing the targeted gene encoding transcript factor for increase the flavonoid production through genetic engineering in G. biloba .

During drilling in complex formations, the sliding bearings of roller cone bits are continuously subjected to low-speed, heavy-load, and boundary lubrication conditions, under which adhesive failure readily occurs, severely limiting drilling efficiency. To enhance their wear resistance, a bionic texture inspired by shark denticles was designed and compared with conventional rectangular and circular textures. An equivalent pin–disk contact model was established based on Hertzian contact theory, and tribological experiments were conducted under typical formation conditions using a friction and wear testing machine. The friction coefficient, friction torque, and wear volume of different textures were measured under both lubricated and dry contact conditions, and the underlying mechanisms were elucidated through three-dimensional surface morphology analysis. The results show that the shark denticle-inspired texture reduced the friction coefficient and wear volume by 33.3% and 35%, respectively, under lubrication, while suppressing debris intrusion at the frictional interface under dry contact, thereby providing a degree of surface protection. This study offers theoretical guidance and experimental evidence for advancing the engineering application of bionic tribology in the petroleum industry.

The morphological, physiological, and biochemical characteristics of leaves result from the long-term adaptation of plants to their environment and are closely related to plant growth and development. In this study, 37 prickly ash germplasm resources from 18 production areas were utilized as the subjects of research. Logistic equations, principal component analysis, and cluster analysis were employed to comprehensively evaluate the leaf traits of prickly ash germplasm resources, with an analysis of their correlation with ecological and geographical factors in the production areas. The results showed that the leaf traits of prickly ash germplasms of different origins are substantially different and diverse. The coefficient of variation for the 14 leaf traits was greater than 10%. The coefficient of variation of the compound leaflet number was the highest among all the considered leaf traits, and the coefficient of variation of leaf thickness was the lowest, at 49.86% and 11.37%, respectively. The leaf traits of the prickly ash germplasm originating from Chongqing in Yongchuan, Chongqing in Rongchang, and Yunnan in Honghe ranked highest, whereas the leaf traits of the prickly ash germplasm from Henan in Jiaozuo, Gansu in Tianshui, and Shanxi in Yuncheng ranked lowest. The results of the correlation analysis showed that among the ecological and geographical factors of the origins, latitude had the strongest correlation with the leaf traits of the prickly ash germplasm. As latitude increased, the leaves of prickly ash gradually decreased in size, weight, and leaf shape index. The factor with the second strongest correlation was temperature. The leaves of the prickly ash germplasm originating from warmer climate areas were larger and heavier than those from areas with colder climates. Altitude and longitude did not significantly affect the leaf traits of the prickly ash germplasm, but at similar latitudes, the leaves of the prickly ash germplasm in high-altitude areas were smaller, and the leaves of the prickly ash germplasm in low-altitude areas were larger. These findings can provide valuable references for breeding and the sustainable utilization of new varieties of prickly ash resources.

Background Fraxinus hupehensis is an endangered tree species that is endemic to in China; the species has very high commercial value because of its intricate shape and potential to improve and protect the environment. Its seeds show very low germination rates in natural conditions. Preliminary experiments indicated that gibberellin (GA 3 ) effectively stimulated the seed germination of F. hupehensis . However, little is known about the physiological and molecular mechanisms underlying the effect of GA 3 on F. hupehensis seed germination. Results We compared dormant seeds (CK group) and germinated seeds after treatment with water (W group) and GA 3 (G group) in terms of seed vigor and several other physiological indicators related to germination, hormone content, and transcriptomics. Results showed that GA 3 treatment increases seed vigor, energy requirements, and trans-Zetain (ZT) and GA 3 contents but decreases sugar and abscisic acid (ABA) contents. A total of 116,932 unigenes were obtained from F. hupehensis transcriptome. RNA-seq analysis identified 31,856, 33,188 and 2056 differentially expressed genes (DEGs) between the W and CK groups, the G and CK groups, and the G and W groups, respectively. Up-regulation of eight selected DEGs of the glycolytic pathway accelerated the oxidative decomposition of sugar to release energy for germination. Up-regulated genes involved in ZT (two genes) and GA 3 (one gene) biosynthesis, ABA degradation pathway (one gene), and ABA signal transduction (two genes) may contribute to seed germination. Two down-regulated genes associated with GA 3 signal transduction were also observed in the G group. GA 3 -regulated genes may alter hormone levels to facilitate germination. Candidate transcription factors played important roles in GA 3 -promoted F. hupehensis seed germination, and Quantitative Real-time PCR (qRT-PCR) analysis verified the expression patterns of these genes. Conclusion Exogenous GA 3 increased the germination rate, vigor, and water absorption rate of F. hupehensis seeds . Our results provide novel insights into the transcriptional regulation mechanism of effect of exogenous GA 3 on F. hupehensis seed germination. The transcriptome data generated in this study may be used for further molecular research on this unique species.

Background Zanthoxylum armatum is a globally recognized medicinal and edible plant, the fruit peel color of which is considered an important trait that influences its economic value. In this study, Z. armatum fruits were used at five different stages of development to explore the law of metabolite biosynthesis and its potential molecular mechanism. Results Using transcriptomic and widely-targeted metabolomic analyses, 23 differentially accumulated metabolites, 274 differentially expressed structural genes, and 230 differentially expressed transcription factor genes associated with anthocyanin synthesis were identified. Based on co-expression network analysis, key structural genes positively associated with anthocyanin biosynthesis were identified and the corresponding hub transcription factor genes were predicted. Cyanidin-3- O -arabinoside, cyanidin-3- O -glucoside, cyanidin-3- O -(2ʹʹ- O -glucosyl)glucoside, cyanidin-3- O -(6’’- O -malonyl)glucoside, cyanidin-3- O -rutinoside, cyanidin-3- O -galactoside, and petunidin-3- O -glucoside-5- O -arabinoside were identified as key anthocyanins accumulated in the peel of mature Z. armatum fruits, the synthesis of which appeared to involve the structural genes PAL5 , PAL8 , PAL9 , PAL11 , PAL13 , PAL14 , C4H2 , CHS17 , F3’H2 , DFR1 , ANS2 , and ANS4 as candidate catalysts. Furthermore, dual-luciferase reporter assays indicated that bHLH-MYC9 and MYB19 may trans-activate the promoters of ANS2 and ANS4 , respectively. Conclusions Our findings in this study provide new perspectives regarding the regulation of peel color development during the ripening of Z. armatum fruit.

Low temperatures are a key factor affecting the growth, development, and geographical distribution of prickly ash. This study investigated the impact of ecological and geographical factors on the freezing tolerance of prickly ash germplasm. Thirty-seven germplasm samples from 18 different origins were collected, and their freezing tolerance was comprehensively evaluated. The correlation between freezing tolerance and the ecological and geographical factors of their origins was also analyzed. Significant differences in freezing tolerance were observed among germplasm from different origins. The semi-lethal temperature of the germplasm ranged from − 12.37 to 1.08 °C. As temperatures decreased, the relative conductivity (REC) and catalase (CAT) activity of the germplasm gradually increased, while soluble sugar (SS), soluble protein (SP), free proline (Pro), and Peroxidase (POD) activities decreased and then increased. Superoxide dismutase (SOD) activity initially increased and then decreased. A comprehensive evaluation of freezing tolerance was conducted using a logistic equation, membership function, and cluster analysis. Germplasm from Tongchuan and Hancheng (Shaanxi Province, China), Asakura (Japan), and Yuncheng (Shanxi Province, China) exhibited the highest freezing tolerance, whereas those from Rongchang (Chongqing Municipality, China), Qujing (Yunnan Province, China), and Honghe (Yunnan Province, China) had the lowest. The correlation analysis revealed a significant positive correlation between freezing tolerance and latitude, and a significant negative correlation with the temperature of origin. Germplasm from higher latitudes showed higher SS content, SOD and CAT activities, stronger antioxidant enzyme activity, and better freezing tolerance compared to those from lower latitudes. REC was lower in germplasm originating from low-temperature areas than in those from high-temperature areas. Additionally, SP, Pro content, SOD, and POD activities were higher, indicating effective scavenging of active oxygen free radicals. No significant correlation was found between altitude and longitude of origin and freezing tolerance. However, at similar latitudes, prickly ash from higher altitudes displayed higher antioxidant enzyme activity and stronger freezing tolerance compared to those from lower altitudes. These findings provide a scientific basis for breeding prickly ash cultivars suited to different ecological regions.

This study aimed to reveal the diversity and variation in panicle traits of the Chinese prickly ash and clarify their influence on the its systematic classification to provide a theoretical basis and technical support for the efficient utilization of Chinese prickly ash germplasm resources and breeding. Sixteen panicle traits were identified from 35 Chinese prickly ash germplasm resources from 2021 to 2022. The diversity of these panicle traits and their role in the plant’s systematic classification were studied using variance, correlation, cluster, and principal component analyses. Cluster analysis showed that the 35 Chinese prickly ash germplasm resources could be divided into two groups with Euclidean distances of 25. Further analysis showed that yield traits such as panicle length, panicle width, primary branching, grain number per panicle, and grain weight per panicle were significantly positively correlated with grain chlorophyll content, while grain anthocyanin content was negatively correlated with both panicle (panicle length, panicle width, panicle length to width ratio, primary branching, grain number per panicle, and grain weight per panicle) and grain characteristics (single grain weight, thousand-grain weight, grain length, grain width and fruit shape index). In conclusion, Chinese prickly ash germplasms have diverse panicle traits. Z. armatum has dark green grains, long and wide panicles, a long conical shape, many primary branches, high grain weight, and high grain number per panicle. In contrast, Z. bungeanum has bright red seeds, a panicle width larger than its length, short and conical panicles, a small number of primary branches, and low grain weight per panicle and number of grains per panicle. Overall, Z. armatum had a significant yield advantage over Z. bungeanum .

Background Zanthoxylum armatum is a vital economic crop in China, but its cultivation is challenged by abiotic stresses like drought and cold. Mitogen-activated protein kinase kinases (MAPKKs) are central signaling components regulating plant stress responses. However, the MAPKK gene family in Z. armatum remained uncharacterized. This study aimed to identify ZaMAPKK genes and elucidate their roles in stress adaptation. Understanding ZaMAPKK functions provides critical genetic targets for molecular breeding programs aimed at developing stress-tolerant cultivars, ensuring sustainable Z. armatum production in marginal environments. Results This study identified 14 MAPKK family members in Z. armatum ( ZaMAPKK1-14 ) via genome-wide analysis. Bioinformatics and experimental analyses revealed that ZaMAPKKs were unstable hydrophilic proteins, predominantly localized in the nucleus. Phylogenetic analysis divided them into four subfamilies (A, B, C, and D), showing high homology with dicotyledonous plants such as Arabidopsis thaliana and soybean. Gene structure analysis indicated significant differences in intron numbers among subfamily members, suggesting functional differentiation. Promoter cis -element analysis identified abundant elements related to light response, hormone regulation, and stress in all genes. Transcriptome and reverse transcription-quantitative PCR (RT-qPCR) analyses revealed that ZaMAPKK7 and ZaMAPKK11 exhibited significantly higher expression across samples from different latitudes, implicating them in regulating Z. armatum stress resistance via activation of stress response pathways. Gene co-expression network analysis indicated that ZaMAPKK genes cooperate with various transcription factors to regulate stress response, light signaling, growth, and metabolism in Z. armatum . Conclusions This study identifies ZaMAPKK7 and ZaMAPKK11 as key regulators of stress resistance in Z. armatum . Future work will integrate RT-qPCR and co-expression analyses to validate their functions within the MAPKK cascade and explore synergistic mechanisms with other gene families. Unraveling this regulatory network will accelerate the breeding of stress-tolerant cultivars, ultimately enhancing Zanthoxylum productivity and industrial sustainability.

Phosphoenolpyruvate carboxylase (PEPC) is a crucial enzyme in plant photosynthesis and stress responses, yet its gene family remained uncharacterized in Zanthoxylum armatum. This study presents the first genome-wide identification and comprehensive analysis of the PEPC gene family in Z. armatum. A total of 12 ZaPEPC genes were identified and classified into plant-type (PTPC) and bacterial-type (BTPC) subfamilies based on phylogenetic analysis. These genes exhibited conserved protein domains but distinct gene structures, with evidence of gene duplication events contributing to family expansion. Promoter analysis revealed an abundance of stress- and hormone-responsive cis-elements, particularly those related to light, abscisic acid (ABA), and methyl jasmonate (MeJA). Expression profiling demonstrated that ZaPEPC genes display environment-specific expression patterns, with ZaPEPC7 and ZaPEPC11 showing significantly higher expression in high-altitude, high-light environments (Yunnan) compared to other regions (Shandong and Chongqing). Co-expression network analysis further indicated interactions between specific ZaPEPCs and stress-related transcription factors. These findings systematically reveal the molecular characteristics and potential roles of the ZaPEPC gene family in environmental adaptation, providing valuable genetic resources and a theoretical foundation for improving stress tolerance and photosynthetic efficiency in Z. armatum through molecular breeding.

In this study, we prepared high-nitrogen self-doped porous carbons (NPC1 and NPC2) derived from the pruned branches and seeds of Zanthoxylum bungeanum using a simple one-step method. NPC1 and NPC2 exhibited elevated nitrogen contents of 3.56% and 4.22%, respectively, along with rich porous structures, high specific surface areas of 1492.9 and 1712.7 m2 g−1 and abundant surface groups. Notably, both NPC1 and NPC2 demonstrated remarkable adsorption abilities for the pollutant methylene blue (MB), with maximum monolayer adsorption capacities of 568.18 and 581.40 mg g−1, respectively. The adsorption kinetics followed the pseudo-second-order kinetics and the adsorption isotherms conformed to the Langmuir isotherm model. The adsorption mechanism primarily relied on the hierarchical pore structures of NPC1 and NPC2 and their diverse strong interactions with MB molecules. This study offers a new approach for the cost-effective design of nitrogen self-doped porous carbons, facilitating the efficient removal of MB from wastewater.