In plants, male sterility can be caused either by mitochondrial genes with coupled nuclear genes or by nuclear genes alone; the resulting conditions are known as cytoplasmic male sterility (CMS) and ...genic male sterility (GMS), respectively. CMS and GMS facilitate hybrid seed production for many crops and thus allow breeders to harness yield gains associated with hybrid vigor (heterosis). In CMS, layers of interaction between mitochondrial and nuclear genes control its male specificity, occurrence, and restoration of fertility. Environment-sensitive GMS (EGMS) mutants may involve epigenetic control by noncoding RNAs and can revert to fertility under different growth conditions, making them useful breeding materials in the hybrid seed industry. Here, we review recent research on CMS and EGMS systems in crops, summarize general models of male sterility and fertility restoration, and discuss the evolutionary significance of these reproductive systems.
The ageing epigenome and its rejuvenation Zhang, Weiqi; Qu, Jing; Liu, Guang-Hui ...
Nature reviews. Molecular cell biology,
03/2020, Letnik:
21, Številka:
3
Journal Article
Recenzirano
Ageing is characterized by the functional decline of tissues and organs and the increased risk of ageing-associated disorders. Several 'rejuvenating' interventions have been proposed to delay ageing ...and the onset of age-associated decline and disease to extend healthspan and lifespan. These interventions include metabolic manipulation, partial reprogramming, heterochronic parabiosis, pharmaceutical administration and senescent cell ablation. As the ageing process is associated with altered epigenetic mechanisms of gene regulation, such as DNA methylation, histone modification and chromatin remodelling, and non-coding RNAs, the manipulation of these mechanisms is central to the effectiveness of age-delaying interventions. This Review discusses the epigenetic changes that occur during ageing and the rapidly increasing knowledge of how these epigenetic mechanisms have an effect on healthspan and lifespan extension, and outlines questions to guide future research on interventions to rejuvenate the epigenome and delay ageing processes.
The current study aimed to investigate the sagittal morphology of the spinopelvic complex and the components of the lumbar spine in the normal population. In total, 132 adult volunteers were ...retrospectively evaluated and divided into four groups according to the Roussouly classification. Statistical analysis of radiological parameters, including lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), PI–LL, LL–TK, lumbar vertebral lordosis from L1 to L5 (L1L–L5L), the intervertebral angle from L1–L2 to L5–S1 (IVA1‐2–IVA5‐1), segmental lordosis from L1 to L5 (S1L–S5L), the proportion of L1–L5 (L1%–L5%), the proportion of the intervertebral angle from L1–L2 to L5–S1 (IVA1‐2%–IVA5‐1%), and proportion of segmental lordosis from L1 to L5 (S1L%–S5L%), was performed. Based on the classification, type II (n = 46) was the most common, followed by type I (n = 39), type III (n = 36), and type IV (n = 11). The quantitative values of the sagittal parameters of the four groups were obtained. Results showed a significant difference in terms of LL, PI, SS, and LL‐TK. Further, L1%, L2%, L3%, IVA1‐2%, IVA2‐3%, S1L%, S2L%, and S3L% had an increasing trend. PI was positively correlated with LL, S1L, S2L, S3L, S4L, S1L%, and S2L%, but not with S5L%. In conclusion, pelvic parameters had a significant effect on lumbar curvature and lordosis distribution. Further, the abovementioned results were beneficial for individual surgical decision‐making regarding targeted intervertebral angle, screw‐insertion dimension, and rod contouring.
Maintaining metabolic homeostasis is essential for cellular and organismal health throughout life. Multiple signaling pathways that regulate metabolism also play critical roles in aging, such as ...PI3K/AKT, mTOR, AMPK, and sirtuins (SIRTs). Among them, sirtuins are known as a protein family with versatile functions, such as metabolic control, epigenetic modification and lifespan extension. Therefore, by understanding how sirtuins regulate metabolic processes, we can start to understand how they slow down or accelerate biological aging from the perspectives of metabolic regulation. Here, we review the biology of SIRT3, SIRT4, and SIRT5, known as the mitochondrial sirtuins due to their localization in the mitochondrial matrix. First, we will discuss canonical pathways that regulate metabolism more broadly and how these are integrated with aging regulation. Then, we will summarize the current knowledge about functional differences between SIRT3, SIRT4, and SIRT5 in metabolic control and integration in signaling networks. Finally, we will discuss how mitochondrial sirtuins regulate processes associated with aging and aging-related diseases.
Epidemiologists have recently investigated sunlight exposure as a risk factor for age-related macular degeneration (AMD), but there remains an ongoing dispute over this association due to ...insufficient evidence and unreliable data.
To analyse comprehensively the epidemiological literature concerning the association between AMD and sunlight exposure.
We systematically reviewed the epidemiological literature concerning the association between AMD and sunlight exposure. An electronic search was performed of PubMed, Web of Science and CNKI, which was supplemented by hand searching. The selection of studies, data abstraction and quality assessment were performed independently by three reviewers. After these steps, we performed a random-effects meta-analysis, followed by subgroup analysis and sensitivity analysis, including a random-effects meta-regression for study-specific covariates.
Fourteen studies were identified. Twelve studies identified an increasing risk of AMD with greater sunlight exposure, six of which reported significant risks. The pooled OR was 1.379 (95% CI 1.091 to 1.745). The subgroup of non-population-based studies revealed a significant risk (OR 2.018, 1.248 to 3.265, p=0.004). We identified the gross domestic product (GDP) per capita (p=0.048), but not the latitude (p=0.21), as a factor that led to heterogeneity according to the meta-regression.
The epidemiological literature published to date indicates that individuals with more sunlight exposure are at a significantly increased risk of AMD. The OR significantly decreased with increasing GDP per capita.
In this work, we rationally designed a series of crystalline and stable dioxin‐linked metallophthalocyanine covalent organic frameworks (COFs; MPc‐TFPN COF, M=Ni, Co, Zn) under the guidance of ...reticular chemistry. As a novel single‐site catalysts (SSCs), NiPc/CoPc‐TFPN COF exhibited outstanding activity and selectivity for electrocatalytic CO2 reduction (ECR; Faradaic efficiency of CO (FECO)=99.8(±1.24) %/ 96.1(±1.25) % for NiPc/CoPc‐TFPN COF). More importantly, when coupled with light, the FECO and current density (jCO) were further improved across the applied potential range (−0.6 to −1.2 V vs. RHE) compared to the dark environment for NiPc‐TFPN COF (jCO increased from 14.1 to 17.5 A g−1 at −0.9 V; FECO reached up to ca. 100 % at −0.8 to −0.9 V). Furthermore, an in‐depth mechanism study was established by density functional theory (DFT) simulation and experimental characterization. For the first time, this work explored the application of COFs as photo‐coupled electrocatalysts to improve ECR efficiency, which showed the potential of using light‐sensitive COFs in the field of electrocatalysis.
A series of stable dioxin‐linked metallophthalocyanine covalent organic frameworks (COFs) were developed and applied for photo‐coupled electrocatalytic CO2 reduction. This work represents a new insight for the future rational design of light sensitive crystalline materials for CO2 reduction.
Aging is associated with a progressive decline in cardiovascular structure and function. Accumulating evidence links cardiovascular aging to epigenetic alterations encompassing a complex interplay of ...DNA methylation, histone posttranslational modifications, and dynamic nucleosome occupancy governed by numerous epigenetic factors. Advances in genomics technology have led to a profound understanding of chromatin reorganization in both cardiovascular aging and diseases. This review summarizes recent discoveries in epigenetic mechanisms involved in cardiovascular aging and diseases and discusses potential therapeutic strategies to retard cardiovascular aging and conquer related diseases through the rejuvenation of epigenetic signatures to a young state.
Background
The pandemic of coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection has made widespread impact recently. We aim to ...investigate the clinical characteristics of COVID‐19 children with different severities and allergic status.
Methods
Data extracted from the electronic medical records, including demographics, clinical manifestations, comorbidities, laboratory and immunological results, and radiological images of 182 hospitalized COVID‐19 children, were summarized and analyzed.
Results
The median age was 6 years, ranging from 3 days to 15 years, and there were more boys (male‐female ratio about 2:1) within the studied 182 patients. Most of the children were infected by family members. Fever (43.4%) and dry cough (44.5%) were common symptoms, and gastrointestinal manifestations accounted for 11.0%, including diarrhea, abdominal discomfort, and vomiting. 71.4% had abnormal chest computed tomography (CT) scan images, and typical signs of pneumonia were ground‐glass opacity and local patchy shadowing on admission. Laboratory results were mostly within normal ranges, and only a small ratio of lymphopenia (3.9%) and eosinopenia (29.5%) were observed. The majority (97.8%) of infected children were not severe, and 24 (13.2%) of them had asymptomatic infections. Compared to children without pneumonia (manifested as asymptomatic and acute upper respiratory infection), children with pneumonia were associated with higher percentages of the comorbidity history, symptoms of fever and cough, and increased levels of serum procalcitonin, alkaline phosphatase, and serum interleukins (IL)‐2, IL‐4, IL‐6, IL‐10, and TNF‐α. There were no differences in treatments, duration of hospitalization, time from first positive to first negative nucleic acid testing, and outcomes between children with mild pneumonia and without pneumonia. All the hospitalized COVID‐19 children had recovered except one death due to intussusception and sepsis. In 43 allergic children with COVID‐19, allergic rhinitis (83.7%) was the major disease, followed by drug allergy, atopic dermatitis, food allergy, and asthma. Demographics and clinical features were not significantly different between allergic and nonallergic groups. Allergic patients showed less increase in acute phase reactants, procalcitonin, D‐dimer, and aspartate aminotransferase levels compared with all patients. Immunological profiles including circulating T, B, and NK lymphocyte subsets, total immunoglobulin and complement levels, and serum cytokines did not show any difference in allergic and pneumonia groups. Neither eosinophil counts nor serum total immunoglobulin E (IgE) levels showed a significant correlation with other immunological measures, such as other immunoglobulins, complements, lymphocyte subset numbers, and serum cytokine levels.
Conclusion
Pediatric COVID‐19 patients tended to have a mild clinical course. Patients with pneumonia had higher proportion of fever and cough and increased inflammatory biomarkers than those without pneumonia. There was no difference between allergic and nonallergic COVID‐19 children in disease incidence, clinical features, and laboratory and immunological findings. Allergy was not a risk factor for developing and severity of SARS‐CoV‐2 infection and hardly influenced the disease course of COVID‐19 in children.
There is no difference between allergic and nonallergic children in clinical features and laboratory/immunological findings, and allergy is not a risk factor for COVID‐19. The majority (97.8%) of infected children were not severe, and 24 (13.2%) of them had asymptomatic infections. Laboratory results were mostly within normal ranges, and only a small ratio of lymphopenia (3.9%) and eosinopenia (29.5%) was observed. Higher proportion of patients with pneumonia have fever, cough, comorbidities, and increased inflammatory biomarkers (procalcitonin, alkaline phosphatase and serum interleukins (IL)‐2, IL‐4, IL‐6, IL‐10, and TNF‐α) than those without pneumonia. Abbreviations: AD, atopic dermatitis; AR, allergic rhinitis; AST, aspartate aminotransferase, AURI, acute upper respiratory infection; COVID‐19, coronavirus disease 2019; DA, drug allergy; FA, food allergy; PCT, procalcitonin; SARS‐CoV‐2, severe acute respiratory syndrome coronavirus 2; TNF, tumor necrosis factor.
Rice blast is one of the most destructive diseases affecting rice worldwide. The adoption of host resistance has proven to be the most economical and effective approach to control rice blast. In ...recent years, sequence-specific nucleases (SSNs) have been demonstrated to be powerful tools for the improvement of crops via gene-specific genome editing, and CRISPR/Cas9 is thought to be the most effective SSN. Here, we report the improvement of rice blast resistance by engineering a CRISPR/Cas9 SSN (C-ERF922) targeting the OsERF922 gene in rice. Twenty-one C-ERF922-induced mutant plants (42.0%) were identified from 50 T0 transgenic plants. Sanger sequencing revealed that these plants harbored various insertion or deletion (InDel) mutations at the target site. We showed that all of the C-ERF922-induced allele mutations were transmitted to subsequent generations. Mutant plants harboring the desired gene modification but not containing the transferred DNA were obtained by segregation in the T1 and T2 generations. Six T2 homozygous mutant lines were further examined for a blast resistance phenotype and agronomic traits, such as plant height, flag leaf length and width, number of productive panicles, panicle length, number of grains per panicle, seed setting percentage and thousand seed weight. The results revealed that the number of blast lesions formed following pathogen infection was significantly decreased in all 6 mutant lines compared with wild-type plants at both the seedling and tillering stages. Furthermore, there were no significant differences between any of the 6 T2 mutant lines and the wild-type plants with regard to the agronomic traits tested. We also simultaneously targeted multiple sites within OsERF922 by using Cas9/Multi-target-sgRNAs (C-ERF922S1S2 and C-ERF922S1S2S3) to obtain plants harboring mutations at two or three sites. Our results indicate that gene modification via CRISPR/Cas9 is a useful approach for enhancing blast resistance in rice.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel‐catalyzed switchable site‐selective alkene ...hydroalkylation. The selection of reaction temperatures leads to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate. This protocol allows the convenient synthesis of α‐ and β‐branched protected amines, both of which are important to the fields of pharmaceutical chemistry and biochemistry. In addition, enantioenriched β‐branched alkylamines can be accessed in a catalytic asymmetric variant. Preliminary mechanistic studies indicate that the formation of a more stable nickelacycle provides the driving force of migration. The thermodynamic and kinetic properties of different reduction elimination intermediates are responsible for the switchable site‐selectivity.
A nickel‐catalyzed switchable site‐selective alkene hydroalkylation was developed. The selection of reaction temperatures led to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate.
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