Search

Abstract Background The R2R3-MYB transcription factors in plants participate in various physiological and biochemical processes and responds to various external stimuli. Prunus sibirica (known as Siberian apricot) is a drupe tree species that produces extremely high nutritional value kernels. However, it is susceptiblility to frost damage during the flowering period, results in a marked reduction in kernel yield. Results In this study, the MYB gene family of P. sibirica (PsMYB) was systematically analyzed, and 116 R2R3-MYB genes that were distributed unevenly over eight chromosomes were ultimately screened. Phylogenetic analysis divided these 116 genes into 30 subgroups. We discovered that 37 PsMYBs had cold stress-responsive promoters, and six PsMYBs were annotated to be associated with cold response. Intraspecific homology analysis identified segmental duplication as the primary gene amplification mechanism, and homology analysis of the PsMYB genes with those of five other species revealed phylogenetic relationships with Rosaceae species. Protein interaction studies revealed collaborative regulation of the PsMYB proteins with Arabidopsis protein, and transcriptome analysis identified PsMYB genes that were highly expressed at low temperatures. Additionally, the expression levels of 22 PsMYBs in different tissue parts of P. sibirica and under different low-temperature stress conditions were evaluated using quantitative real-time PCR, with the results verifying that PsMYBs are specifically expressed in different plant parts and may be involved in the growth and development of P. sibirica species. Genes upregulated after exposure to low-temperature stress and likely involved in cold response were identified. Conclusion This study lays a foundation for understanding the molecular biology of PsMYBs in P. sibirica and provides a theoretical basis for the future study of transgenic lines with cold resistance during the flowering period of this tree.

Abstract Background AP2/ERF transcription factors are involved in the regulation of growth, development, and stress response in plants. Although the gene family has been characterized in various species, such as Oryza sativa, Arabidopsis thaliana, and Populus trichocarpa, studies on the Prunus sibirica AP2/ERF (PsAP2/ERF) gene family are lacking. In this study, PsAP2/ERFs in P. sibirica were characterized by genomic and transcriptomic analyses. Results In the study, 112 PsAP2/ERFs were identified and categorized into 16 subfamilies. Within each subfamily, PsAP2/ERFs exhibited similar exon-intron structures and motif compositions. Additionally, 50 pairs of segmentally duplicated genes were identified within the PsAP2/ERF gene family. Our experimental results showed that 20 PsAP2/ERFs are highly expressed in leaves, roots, and pistils under low-temperature stress conditions. Among them, the expression of PsAP2/ERF21, PsAP2/ERF56 and PsAP2/ERF88 was significantly up-regulated during the treatment period, and it was hypothesised that members of the PsAP2/ERF family play an important role inlow temperature stress tolerance. Conclusions This study improves our understanding of the molecular basis of development and low-temperature stress response in P. sibirica and provides a solid scientific foundation for further functional assays and evolutionary analyses of PsAP2/ERFs.

Abstract The pathogenesis of aortic dissection (AD), an aortic disease associated with high mortality, involves significant vascular inflammatory infiltration. However, the precise relationship between perivascular adipose tissue (PVAT) and aortic dissection remains incompletely understood. The objective of this study is to investigate the role of PVAT inflammation in the pathogenesis of aortic dissection and identify novel therapeutic targets for this disease. The mouse model of aortic dissection was established in this study through intraperitoneal injection of Ang II and administration of BAPN in drinking water. Additionally, control groups were established at different time points including the 2-week group, 3-week group, and 4-week group. qPCR and immunohistochemistry techniques were employed to detect the expression of inflammatory markers and RUNX1 in PVAT surrounding the thoracic aorta in mice. Additionally, an aortic dissection model was established using RUNX1 knockout mice, and the aforementioned indicators were assessed. The 3T3-L1 cells were induced to differentiate into mature adipocytes in vitro, followed by lentivirus transfection for the knockdown or overexpression of RUNX1. The study aimed to investigate the potential cell-to-cell interactions by co-culturing 3T3-L1 cells with A7r5 or RAW264.7 cells. Subsequently, human aortic PVAT samples were obtained through clinical surgery and the aforementioned indicators were detected. In comparison to the control group, the aortic dissection model group exhibited decreased expression of MMP-2 and NF-κB in PVAT, while TNF-α and RUNX1 expression increased. Suppression of RUNX1 expression resulted in increased MMP-2 and NF-κB expression in PVAT, along with decreased TNF-α expression. Overexpression of RUNX1 upregulated the expression levels of NF-Κb, MMP-2, and TNF-α in adipocytes, whereas knockdown of RUNX1 exerted an opposite effect. Macrophages co-cultured with adipocytes overexpressing RUNX1 exhibited enhanced CD86 expression, while vascular smooth muscle cells co-cultured with these adipocytes showed reduced α-SMA expression. In human samples, there was an increase in both RUNX1 and MMP-2 expression levels, accompanied by a decrease in TNF-α and NF-Κb expression. The presence of aortic dissection is accompanied by evident inflammatory alterations in the PVAT, and this phenomenon appears to be associated with the involvement of RUNX1. It is plausible that the regulation of PVAT's inflammatory changes by RUNX1/NF-κB signaling pathway plays a role in the pathogenesis of aortic dissection.

Primary cardiac malignant tumors are extremely rare, making up about 10% of all primary cardiac tumors. Most of these tumors are primary sarcomas, with primary mesothelioma being even less common. This report details a 53-year-old male patient diagnosed with primary cardiac malignant mesothelioma. The patient had symptoms of chest pain and difficulty breathing. A CT scan showed an enlarged heart, fluid around the heart, and irregular thickening of the pericardium. Diagnosis was confirmed through a surgical biopsy, which showed the presence of malignant mesothelioma. After the procedure, the patient received appropriate cardiac support. Although stable at discharge, the patient unfortunately died three months later due to severe wheezing. There may be a potential link between exposure to radioactive iodine treatment and this outcome. This case highlights the diagnostic and treatment challenges of primary cardiac malignant tumors and reminds physicians to consider this rare disease when evaluating patients with similar symptoms.

To investigate the low-temperature adaptability of different provenances of Ziziphus jujuba var. spinosa, we used 21 clones from seven provenances as experimental materials and observed the changes in physiological and biochemical indicators and the characteristics of anatomical structures under low-temperature stress. A comprehensive evaluation of their cold resistance was conducted using the membership function method. As the temperature decreased, the relative electrical conductivity (REC) of clone 89 became stable and had the lowest LT50 value (−44.04 °C). The cold-resistant Z. jujuba var. spinosa had a higher bound water/free water (BW/FW) ratio and antioxidant enzyme activity and accumulated large quantities of osmotic regulatory substances. Higher xylem, phloem, and xylem–cortex ratios and greater conduit density enhanced the cold resistance of Z. jujuba var. spinosa. The membership function values of clones 89, 90, 91, 604, and 612 were greater than 0.6, indicating that they could be evaluated as resources with the potential for low-temperature resistance. The cold resistance rankings for the different provenances were as follows: Kazuo, Liaoning > Jiaxian, Shaanxi > Fuxing, Heibei > Changqing, Shandong > Neiqiu, Heibei > Yanchuan, Shaanxi > Xiaxian, Shanxi. These results provide a scientific basis for the rapid and accurate identification of cold resistance in Z. jujuba var. spinosa resources and the breeding and cultivation of new cold-resistant varieties of this subspecies.

Abstract Siberian apricot (Prunus sibirica L.) is a woody tree species of ecological, economic, and social importance. To evaluate the genetic diversity, differentiation, and structure of P. sibirica, we analyzed 176 individuals from 10 natural populations using 14 microsatellite markers. These markers generated 194 alleles in total. The mean number of alleles (13.8571) was higher than the mean number of effective alleles (6.4822). The average expected heterozygosity (0.8292) was higher than the average observed heterozygosity (0.3178). Shannon information index and polymorphism information content were separately 2.0610 and 0.8093, demonstrating the rich genetic diversity of P. sibirica. Analysis of molecular variance revealed that 85% of the genetic variation occurred within populations, with only 15% among them. The genetic differentiation coefficient and gene flow were separately 0.151 and 1.401, indicating a high degree of genetic differentiation. Clustering results showed that a genetic distance coefficient of 0.6 divided the 10 natural populations into two subgroups (subgroups A and B). STRUCTURE and principal coordinate analysis divided the 176 individuals into two subgroups (clusters 1 and 2). Mantel tests revealed that genetic distance was correlated with geographical distance and elevation differences. These findings can contribute to the effective conservation and management of P. sibirica resources.

Abstract Background WRKY transcription factors are a prominent gene family in plants, playing a crucial role in various biological processes including development, metabolism, defense, differentiation, and stress response. Although the WRKY gene family has been extensively studied and analysed in numerous plant species, research on Prunus sibirica’s WRKY genes (PsWRKY) remains lacking. Results This study analysed the basic physicochemical properties, phylogeny, gene structure, cis-acting elements, and Gene ontology (GO) annotation of PsWRKY gene family members using bioinformatics methods based on the whole-genome data of P. sibirica. In total, 55 WRKYs were identified in P. sibirica and were heterogeneously distributed on eight chromosomes. Based on the phylogenetic analysis, these WRKYs were classified into three major groups: Group I, Group II (II-a, II-b, II-c, II-d, II-e), and Group III. Members of different subfamilies have different cis-acting elements, conserved motifs, and intron-exon structures, indicating functional heterogeneity of the WRKY family. Prediction of subcellular localisation indicated that PsWRKYs were mainly located in the nucleus. Twenty pairs of duplicated genes were identified, and segmental duplication events may play an important role in PsWRKY gene family expansion. Analysis of the Ka/Ks ratio showed that the PsWRKY family’s homologous genes were primarily purified by selection. Additionally, GO annotation analysis showed that the WRKY gene family was mainly involved in responses to stimuli, immune system processes, and reproductive processes. Furthermore, quantitative real-time PCR (qRT-PCR) analysis showed that 23 PsWRKYs were highly expressed in one or more tissues (pistils and roots) and PsWRKYs showed specific expression patterns under different low-temperature stress conditions. Conclusions Our results provide a scientific basis for the further exploration and functional validation of WRKYs in P. sibirica.

The basic helix-loop-helix (bHLH) family is one of the most well-known transcription factor families in plants, and it regulates growth, development, and abiotic stress responses. However, systematic analyses of the bHLH gene family in Prunus sibirica have not been reported to date. In this study, 104 PsbHLHs were identified and classified into 23 subfamilies that were unevenly distributed on eight chromosomes. Nineteen pairs of segmental replication genes and ten pairs of tandem replication genes were identified, and all duplicated gene pairs were under purifying selection. PsbHLHs of the same subfamily usually share similar motif compositions and exon-intron structures. PsbHLHs contain multiple stress-responsive elements. PsbHLHs exhibit functional diversity by interacting and coordinating with other members. Twenty PsbHLHs showed varying degrees of expression. Eleven genes up-regulated and nine genes down-regulated in −4°C. The majority of PsbHLHs were highly expressed in the roots and pistils. Transient transfection experiments demonstrated that transgenic plants with overexpressed PsbHLH42 have better cold tolerance. In conclusion, the results of this study have significant implications for future research on the involvement of bHLH genes in the development and stress responses of Prunus sibirica.

In Prunus sibirica, the phenomenon of pistil abortion is very common and seriously affects its fruit quality and yield; however, the molecular mechanisms of pistil abortion remains unclear. In this study, we identified differentially expressed genes (DEGs) and pathways associated with pistil abortion using transcriptome sequencing. After comparative analysis, a total of 1,950 DEGs were identified, of which 1,000 were upregulated, and 950 were downregulated. Gene Ontology (GO) functional enrichment analysis of DEGs showed that metabolic process, cellular process, single-organism process, membrane, membrane part, cell, binding, catalytic activity, and transporter activity contained the largest number of DEGs. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the plant-pathogen interaction, starch and sucrose metabolism, and plant hormone signal transduction pathways contained the largest number of DEGs. The NAC, bHLH, and B3 transcription factor families contained the largest number of DEGs. qRT-PCR detection confirmed that the gene expression levels were consistent with the transcriptome sequencing results. This study provides a theoretical basis and scientific basis for further research on the molecular mechanisms of P. sibirica pistil abortion.

The genetic diversity and genetic structure of P. armeniaca var. ansu were analyzed based on SSR markers. The aim was to provide scientific basis for conservation, efficient utilization, molecular marker assisted breeding and improved variety selection of P. armeniaca var. ansu germplasm resources. The results showed that the level of genetic diversity within the population was high. Among the 30 SSR markers, the mean number of observed alleles was 11.433, the mean number of effective alleles was 4.433, the mean of Shannon information index was 1.670, and the mean of polymorphic information content was 0.670. Among the eight provenances, Tuanjie Township, Xinyuan County, Xinjiang had the highest genetic diversity. The observed alleles, effective alleles, Shannon information index and Nei’s gene diversity index among provenances were higher than those within provenances. Based on Bayesian mathematical modeling and UPGMA cluster analysis, 86 P. armeniaca var. ansu accessions were divided into three subpopulations and four groups, which reflected individual differences in provenances. Subpopulations classified by Bayesian mathematical modeling and groups classified by UPGMA cluster analysis were significantly correlated with geographical provenance (Sig

Background The phenomenon of male sterility widely occurs in Prunus sibirica and has a serious negative impact on yield. We identified the key stage and cause of male sterility and found differentially expressed genes related to male sterility in Prunus sibirica, and we analyzed the expression pattern of these genes. This work aimed to provide valuable reference and theoretical basis for the study of reproductive development and the mechanisms of male sterility in Prunus sibirica. Method The microstructures of male sterile flower buds and male fertile flower buds were observed by paraffin section. Transcriptome sequencing was used to screen genes related to male sterility in Prunus sibirica. Quantitative real-time PCR analysis was performed to verify the transcriptome data. Results Anther development was divided into the sporogenous cell stage, tetrad stage, microspore stage, and pollen maturity stage. Compared with male fertile flower buds, in the microspore stage, the pollen sac wall tissue in the male sterile flower buds showed no signs of degeneration. In the pollen maturity stage, the tapetum and middle layer were not fully degraded, and anther development stopped. Therefore, the microspore stage was the key stage for anther abortion , and the pollen maturity stage was the post stage for anther abortion. A total of 4,108 differentially expressed genes were identified by transcriptome analysis. Among them, 1,899 were up-regulated, and 2,209 were down-regulated in the transcriptome of male sterile flower buds. We found that “protein kinase activity”, “apoptosis process”, “calcium binding”, “cell death”, “cytochrome c oxidase activity”, “aspartate peptidase activity”, “cysteine peptidase activity” and other biological pathways such as “starch and sucrose metabolism” and “proteasome” were closely related to male sterility in Prunus sibirica. A total of 331 key genes were preliminarily screened. Conclusion The occurrence of male sterility in Prunus sibirica involved many biological processes and metabolic pathways. According to the results of microstructure observations, related physiological indexes determination and transcriptome analysis, we reveal that the occurrence of male sterility in Prunus sibirica may be caused by abnormal metabolic processes such as the release of cytochrome c in the male sterile flower buds, the imbalance of the antioxidant system being destroyed, and the inability of macromolecular substances such as starch to be converted into soluble small molecules at the correct stage of reproductive development, resulting in energy loss. As a result, the tapetum cannot be fully degraded, thereby blocking anther development, which eventually led to the formation of male sterility.

Prunus sibirica is an economically important tree species that occurs in arid and semi-arid regions of northern China. For this species, creation of a core collection is critical for future ecological and evolutionary studies, efficient economic utilization, and development and management of the broader collection of its germplasm resources. In this study, we sampled 158 accessions of P. sibirica from Russia and China using 30 pair of simple sequence repeat molecular markers and 30 different schemes to identify candidate core collections. The 30 schemes were based on combinations of two different sampling strategies, three genetic distances, and five different sample sizes of the complete germplasm resource. We determined the optimal core collection from among the 30 results based on maximization of genetic diversity among groups according to Number of observed alleles (Na), Number of effective alleles (Ne), Shannon’s information index (I), Polymorphic information content (PIC), Nei gene diversity (H) and compared to the initial collection of 158 accessions. We found that the optimal core collection resulted from preferred sampling at 25% with Nei & Li genetic distance these ratios of Na, Ne, I, PIC and H to the complete 158 germplasm resources were 73.0%, 113%, 102%, 100% and 103%, respectively, indicating that the core collection comprised a robust representation of genetic diversity in P. sibirica. The proposed core collection will be valuable for future molecular breeding of this species and management of its germplasm resources.

In this study, the chloroplast genome sequence of Prunus sibirica was obtained from the whole genome sequencing data of Prunus sibirica. Its length is 158,248 bp, which consists of 86,331 bp large single-copy region (LSC), 26,408 bp two reverse repeat regions (IR) and 19,101 bp small single-copy region (SSC). GC content of the whole chloroplast genome is 36.71%. Those of LSC region, SSC region, and IR region were 35, 30, and 43%, respectively. There are 131 unique genes in the chloroplast genome, including 90 protein-coding genes, 33 tRNA genes, and 8 rRNA genes. A maximum-likelihood phylogenetic tree was generated from the chloroplast genomes of 10 species of Rosaceae and 11 peripheral plants. The results showed that Prunus sibirica belongs to Rosaceae and is sister to Prunus salicina.