Pan-mitogenomics reveals the genetic basis of cytonuclear conflicts in citrus hybridization, domestication, and diversification.

Although interactions between the cytoplasmic and nuclear genomes occurred during diversification of many plants, the evolutionary conflicts due to cytonuclear interactions are poorly understood in crop breeding. Here, we constructed a pan-mitogenome and identified chimeric open reading frames (ORFs) generated by extensive structural variations (SVs). Meanwhile, short reads from 184 accessions of citrus species were combined to construct three variation maps for the nuclear, mitochondrial, and chloroplast genomes. The population genomic data showed discordant topologies between the cytoplasmic and nuclear genomes because of differences in mutation rates and levels of heteroplasmy from paternal leakage. An analysis of species-specific SVs indicated that mitochondrial heteroplasmy was common and that chloroplast heteroplasmy was undetectable. Interestingly, we found a prominent divergence in the mitogenomes and the highest genetic load in the, which may provide the basis for cytoplasmic male sterility (CMS) and thus influence the reshuffling of the cytoplasmic and nuclear genomes during hybridization. Using cytoplasmic replacement experiments, we identified a type of species-specific CMS in mandarin related to two chimeric mitochondrial genes. Our analyses indicate that cytoplasmic genomes from mandarin have rarely been maintained in hybrids and that paternal leakage produced very low levels of mitochondrial heteroplasmy in mandarin. A genome-wide association study (GWAS) provided evidence for three nuclear genes that encode pentatricopeptide repeat (PPR) proteins contributing to the cytonuclear interactions in the Citrus genus. Our study demonstrates the occurrence of evolutionary conflicts between cytoplasmic and nuclear genomes in citrus and has important implications for genetics and breeding.

Spatiotemporal profiles of gene activity in stamen delineate nucleo-cytoplasmic interaction in a male-sterile somatic cybrid citrus.

Cytoplasmic male sterility (CMS) has long been used to produce seedless fruits in perennial woody crops like citrus. A male-sterile somatic cybrid citrus (G1 + HBP) was generated by protoplast fusion between a CMS callus parent 'Guoqing No. 1' Satsuma mandarin (Citrus unshiu, G1) and a fertile mesophyll parent Hirado Buntan pummelo (Citrus grandis, HBP). To uncover the male-sterile mechanism of G1 + HBP, we compared the transcriptome profiles of stamen organ and cell types at five stages between G1 + HBP and HBP, including the initial stamen primordia, enlarged stamen primordia, pollen mother cells, tetrads, and microspores captured by laser microdissection. The stamen organ and cell types showed distinct gene expression profiles. A majority of genes involved in stamen development were differentially expressed, especially CgAP3.2, which was downregulated in enlarged stamen primordia and upregulated in tetrads of G1 + HBP compared with HBP. Jasmonic acid- and auxin-related biological processes were enriched among the differentially expressed genes of stamen primordia, and the content of jasmonic acid biosynthesis metabolites was higher in flower buds and anthers of G1 + HBP. In contrast, the content of auxin biosynthesis metabolites was lower in G1 + HBP. The mitochondrial tricarboxylic acid cycle and oxidative phosphorylation processes were enriched among the differentially expressed genes in stamen primordia, meiocytes, and microspores, indicating the dysfunction of mitochondria in stamen organ and cell types of G1 + HBP. Taken together, the results indicate that malfunction of mitochondria-nuclear interaction might cause disorder in stamen development, and thus lead to male sterility in the citrus cybrid.

Delineation of basic farmland based on the quality and spatial stability: a case study of Yingtan City, China.

Delimiting basic farmland is essential to ensure food security and maintain social stability. Determining the quantity and spatial layout of the basic farmland is the main aspect of delimitation. For a long time, superiors in local governments have mainly assigned the basic farmland quantity, which is prone to regional imbalance. The determination of the spatial layout is mainly based on the quality and contiguity of the cultivated land; however, spatial stability is not considered. Therefore, in this study, Yingtan City was used as an example to determine the scale of basic farmland based on the food security and multi-source data, construct a Land Evaluation and Site Assessment System model, evaluate the quality of cultivated land, and integrate the degree of agglomeration and compatibility of cultivated land to characterize its spatial stability. The quality and spatial stability of the cultivated land were combined to construct a matrix. The cultivated land patches must be selected according to the "scale limitation, stability priority, and quality superiority" principle. Finally, basic farmland covering an area of 75,946.34 hm2 was delineated, whose average quality index and spatial stability increased by 0.02 and 0.04, respectively. The landscape structure is more stable than the originally planned structure, which is conducive to the sustainable development of the cultivated land ecosystem. That is, a good delimitation effect was achieved, providing a reference for actual delimitation work.

Scenario-based simulation of land use in Yingtan (Jiangxi Province, China) using an integrated genetic algorithm-cellular automata-Markov model.

Yingtan is a rapidly urbanizing city in Jiangxi Province, South China. During rapid urbanization, construction land is expanded at the expense of cropland and forest. Although economic benefits are gained, ecological and environmental damage is irreversible. In this study, a methodological framework for land use simulation using an integrated genetic algorithm-cellular automata-Markov model is proposed to assess the relationship between economic development and cropland protection in Yingtan. This framework considers both the economic and ecological benefits of different land use types. Three land use scenarios are evaluated to seek recommendations for land use practice. The results show that the areas with high suitability for cropland and construction are mainly concentrated in urban fringes. Under the green development scenario, the area of new construction land can meet the land demand for population growth and economic development proposed for 2025 based on population forecasting and government interviews. The expansion for construction land is decreased by ~ 35 km2 while the cropland area is increased by ~ 20 km2 compared with those under natural and controlled development scenarios. Additionally, ecological losses are lowest under the green development scenario. In conclusion, the green development scenario is conducive to both cropland and ecological protection, which is of relevance for future spatial planning in Yingtan.

Circ-PRMT5 promotes gastric cancer progression by sponging miR-145 and miR-1304 to upregulate MYC.

Background: Gastric cancer (GC) is a global leading source of cancer-associated deaths. Circular RNAs (circRNAs) are a new type of non-coding RNA and promising biomarkers for diagnosis of multiple diseases such as cancer.Methods: Circ-PRMT5 expression was validated in 90 GC patient tissues and 6 different GC cells by qRT-PCR. Sublocalization of circ-PRMT5 in GC cells was determined in isolated nuclear and cytoplasmic RNAs. CircInteractome and miRanda were used to predict binding sites between circ-PRMT5 with micRNAs, and micRNAs with target mRNA. The correlation between genes was determined by the Pearson correlation analysis. The molecular mechanism was demonstrated by RNA in vivo precipitation, point mutation, luciferase activity and rescue experiments.Results: Circ-PRMT5 expression was significantly higher in GC than in adjacent normal tissues, and GC patients with circ-PRMT5 high expression had shorter survival times. Functionally, circ-PRMT5 silence inhibited GC cell growth and invasion. Mechanism analysis showed that circ-PRMT5 sponged miR-145/miR-1304 to upregulate MYC expression and GC development.Conclusion: Our findings demonstrated that circ-PRMT5 function as an oncogene in GC patients by targeting miR-145/miR-1304/MYC axis. High circ-PRMT5 expression may provide a poor prognostic indicator of survival in GC patients and targeting circ-PRMT5/miR-145/miR-1304/MYC axis may be a novel therapeutic strategy for GC.

Influence of autologous blood transfusion in liver transplantation in patients with hepatitis B on the function and hemorheology of red blood cells.

The present study aimed to characterize the function and hemorheology of red blood cells (RBCs) recovered during liver transplantation surgery in patients with hepatitis B and decompensation. A total of 15 hepatitis B patients with decompensation who underwent liver transplantation surgery were included in the present study. Blood samples were recovered during the liver transplantation surgery using an Autologous Blood Recovery System. The morphology and structure of RBCs were characterized and compared between pre-operative and recovered blood samples. In addition, the physiological functions of RBCs were measured and compared between pre-operative and recovered blood samples. No significant differences in the morphological score, 2,3-diphosphoglycerate, Na+K+-ATPase, Ca2+-ATPase, Mg2+-ATPase, malondialdehyde and osmotic fragility were identified between RBCs in the pre-operative and recovered blood samples. The level of free hemoglobin in RBCs of the recovered blood samples was significantly higher than in the pre-operative blood samples (P<0.05). Medium- and high-shear blood viscosities in the recovered blood samples were significantly lower than those observed in the pre-operative blood samples (P<0.05). Casson viscosity in the recovered blood samples was significantly higher compared with the pre-operative blood samples. However, no significant differences (P>0.05) in the low-shear blood viscosity, plasma viscosity, relative blood viscosity, erythrocyte aggregation index or Casson yield stress were identified between recovered and pre-operative blood samples. These findings suggested that autologous blood transfusion in liver transplantation surgery in patients with hepatitis B and decompensation had no significant influence on the morphology, structure, function and hemorheology of RBCs.

A multicenter study of blood component transfusion in patients with liver cirrhosis in China: Patient characteristics, transfusion practice, and outcomes.

BACKGROUND: Cirrhosis is a complex acquired disorder of hemostasis and patients frequently receive blood transfusions. But there is very limited data on patterns of blood use at a patient level. AIMS: To characterize blood use in cirrhotic patients in China and compare with recommendations to help identify areas where quality improvement strategies can be targeted. We also compared findings to a similar study undertaken in UK. METHODS: A cross-sectional study was conducted in 11 hospitals over a 2-month period. Data were collected prospectively on each hospitalized cirrhotic patient to day 28. RESULTS: 1595 cirrhotic patients were included and 20.6% were transfused. 48.2% of transfused patients received transfusion for bleeding, most commonly gastrointestinal bleeding (65.8%). The remaining 51.8% were transfused for non-bleeding indications. 32.5% of patients transfused for gastrointestinal bleeding with red blood cells had a pre-transfusion haemoglobin >7g/dL. 89.1% of patients transfused frozen plasma for non-bleeding indications received them in the absence of a planned procedure. The patterns of blood transfusion in cirrhosis were different between China and UK. Of note, empirical prophylactic use of frozen plasma was more common in the Chinese study (89%) than in the UK (24%). CONCLUSION: Education and research should be implemented to improve patient blood management, especially in prophylactic frozen plasma use area.