Identification and validation of immune-related gene signature models for predicting prognosis and immunotherapy response in hepatocellular carcinoma.

Background: This study seeks to enhance the accuracy and efficiency of clinical diagnosis and therapeutic decision-making in hepatocellular carcinoma (HCC), as well as to optimize the assessment of immunotherapy response. Methods: A training set comprising 305 HCC cases was obtained from The Cancer Genome Atlas (TCGA) database. Initially, a screening process was undertaken to identify prognostically significant immune-related genes (IRGs), followed by the application of logistic regression and least absolute shrinkage and selection operator (LASSO) regression methods for gene modeling. Subsequently, the final model was constructed using support vector machines-recursive feature elimination (SVM-RFE). Following model evaluation, quantitative polymerase chain reaction (qPCR) was employed to examine the gene expression profiles in tissue samples obtained from our cohort of 54 patients with HCC and an independent cohort of 231 patients, and the prognostic relevance of the model was substantiated. Thereafter, the association of the model with the immune responses was examined, and its predictive value regarding the efficacy of immunotherapy was corroborated through studies involving three cohorts undergoing immunotherapy. Finally, the study uncovered the potential mechanism by which the model contributed to prognosticating HCC outcomes and assessing immunotherapy effectiveness. Results: SVM-RFE modeling was applied to develop an OS prognostic model based on six IRGs (CMTM7, HDAC1, HRAS, PSMD1, RAET1E, and TXLNA). The performance of the model was assessed by AUC values on the ROC curves, resulting in values of 0.83, 0.73, and 0.75 for the predictions at 1, 3, and 5 years, respectively. A marked difference in OS outcomes was noted when comparing the high-risk group (HRG) with the low-risk group (LRG), as demonstrated in both the initial training set (P <0.0001) and the subsequent validation cohort (P <0.0001). Additionally, the SVMRS in the HRG demonstrated a notable positive correlation with key immune checkpoint genes (CTLA-4, PD-1, and PD-L1). The results obtained from the examination of three cohorts undergoing immunotherapy affirmed the potential capability of this model in predicting immunotherapy effectiveness. Conclusions: The HCC predictive model developed in this study, comprising six genes, demonstrates a robust capability to predict the OS of patients with HCC and immunotherapy effectiveness in tumor management.

The Identification and Analysis of the Self-Incompatibility Pollen Determinant Factor SLF in Lycium barbarum.

Self-incompatibility is a widespread genetic mechanism found in flowering plants. It plays a crucial role in preventing inbreeding and promoting outcrossing. The genes that control self-incompatibility in plants are typically determined by the S-locus female determinant factor and the S-locus male determinant factor. In the Solanaceae family, the male determinant factor is often the SLF gene. In this research, we cloned and analyzed 13 S2-LbSLF genes from the L. barbarum genome, which are located on chromosome 2 and close to the physical location of the S-locus female determinant factor S-RNase, covering a region of approximately 90.4 Mb. The amino acid sequence identity of the 13 S2-LbSLFs is 58.46%, and they all possess relatively conserved motifs and typical F-box domains, without introns. A co-linearity analysis revealed that there are no tandemly repeated genes in the S2-LbSLF genes, and that there are two pairs of co-linear genes between S2-LbSLF and the tomato, which also belongs to the Solanaceae family. A phylogenetic analysis indicates that the S2-LbSLF members can be divided into six groups, and it was found that the 13 S2-LbSLFs are clustered with the SLF genes of tobacco and Petunia inflata to varying degrees, potentially serving as pollen determinant factors regulating self-incompatibility in L. barbarum. The results for the gene expression patterns suggest that S2-LbSLF is only expressed in pollen tissue. The results of the yeast two-hybrid assay showed that the C-terminal region of S2-LbSLFs lacking the F-box domain can interact with S-RNase. This study provides theoretical data for further investigation into the functions of S2-LbSLF members, particularly for the identification of pollen determinant factors regulating self-incompatibility in L. barbarum.

Effects of different chemical modifications on physicochemical and antioxidation properties of Lycium barbarum seed dreg polysaccharides.

Recent studies have witnessed that chemical modification can improve the physicochemical and functional properties of plants' polysaccharides. Herein, we modified the natural Lycium barbarum seed dreg polysaccharides (LBSDPs) by sulfation (S-LBSDPs), phosphorylation (P-LBSDPs), and carboxymethylation (C-LBSDPs), and evaluated the chemical composition and antioxidant activity of their derivatives. Natural polysaccharides and their derivatives exhibited typical polysaccharide absorption peaks and characteristic group absorption peaks in FT-IR spectra along with maximum UV absorption. After modification, the total sugar and protein contents of the derivatives were decreased, whereas the uronic acid content was increased. Among the three derivatives, sulfated polysaccharides displayed excellent thermal stability. S-LBSDP and P-LBSDP showed the highest ABTS radical scavenging and reducing power while S-LBSDPs and C-LBSDPs showed better DPPH radical scavenging effect, and P-LBSDPs showed considerable Fe2+ chelating ability. Our data indicate that chemical modifications can impart a positive effect on the antioxidant potential of plant-derived polysaccharides.

Curcumin alleviates 1-methyl- 4-phenyl- 1,2,3,6-tetrahydropyridine- induced Parkinson's disease in mice via modulating gut microbiota and short-chain fatty acids.

Background: The microbiota-gut-brain axis has been proposed as a potential therapeutic target of PD. The effects of curcumin against Parkinson's disease have been demonstrated; however, its neuroprotective mechanisms remain unknown. Our study investigated the potential mechanisms through which curcumin ameliorates Parkinson's disease via the microbiota-gut-brain axis. Methods: Mice were randomly divided into four groups: control, Curcumin, MPTP, and MPTP + Curcumin. Motor deficits and gastrointestinal dysfunction were assessed using behavioral test, intestinal motility test, and fecal parameter measurement. The loss of dopaminergic neurons and intestinal barrier function was measured using Western blot and immunofluorescence. Shotgun metagenomic sequencing and LC-MS were parallelly performed on mice feces to investigate alterations in microbiota and metabolites. Results: Curcumin alleviated motor deficits and the loss of dopaminergic neurons in MPTP-induced mice. Curcumin ameliorated gastrointestinal and intestinal barrier dysfunctions in MPTP-induced mice. Curcumin reduced gut microbial dysbiosis and modulated carbohydrate metabolism in MPTP-induced mice. Curcumin restored short-chain fatty acid (SCFA) profiles in MPTP-induced mice. Conclusion: Concurrently, these results indicate that curcumin inhibits Parkinson's disease by regulating the gut microbiota and short-chain fatty acids.

Genotype and clinical phenotype analysis of a Family with Kennedy disease.

To investigate the clinical phenotype-genotype correlations of a family with Kennedy disease (KD) and improve our understanding of the disease. KD was confirmed after clinical phenotypic analyses, laboratory tests, polymerase chain reaction assays for cytosine-adenine-guanine (CAG) repeats, and neuro-electrophysiological tests. The disease was assessed using the KD1234 scale and the spinal and bulbar muscular atrophy functional rating scale. The average age of disease onset was 30.8 ± 2.85 years. Clinically diagnosed members had 48 CAG repeats (≥35 is abnormal) in the androgen receptor gene. The patients exhibited gynecomastia and testicular dysfunction. The lesions mainly involved the medulla oblongata and spinal cord. Progesterone and serum creatine kinase levels were significantly high. Electromyography showed chronic neurogenic damage and abnormal sensory and motor conduction in family members who did not participate in sports, exercise, or physical hobbies. Our study showed that this family had a stable inheritance of CAG repeats, and the genotype was consistent with the clinical phenotype. Gynecomastia was the first symptom, with progressive androgen resistance resulting in testicular atrophy, infertility, and sexual dysfunction. Changes in serum creatine kinase may indicate the progression or relief of symptoms, and rehabilitation may delay the progression of muscle atrophy.

A DOPO-Based Compound Containing Aminophenyl Silicone Oil for Reducing Fire Hazards of Polycarbonate.

A novel P/N/Si-containing flame retardant (marked as DASO) was synthesized through an Atherton-Todd reaction between 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide and aminophenyl silicone oil, and further used for reducing fire hazards of polycarbonate (PC). The chemical structure of DASO was verified via FTIR, 1H, and 31P NMR. Upon the incorporation of 2 wt% DASO, the FRPC composite achieved a high limiting oxygen index (LOI) of 32.2% and a desired UL-94 V-0 rating. In this case, the peak heat release rate (PHRR) and total smoke production (TSP) were reduced by 26% and 44% as compared with the pure PC, respectively. The improved fire safety contributed to the flame retardant roles of DASO in both the condensed phase and gas phase. The presence of DASO promoted the formation of dense and highly graphited char layer in the condensed phase, and released non-combustible gases and phosphorus-containing radicals in the gas phase. Furthermore, the FRPC composites displayed comparable elongation at break but a slightly reduced tensile and impact strength.

A Nitrogen-Rich DOPO-Based Derivate for Increasing Fire Resistance of Epoxy Resin with Comparable Transparency.

To endow synergistically epoxy resin (EP) with excellent fire resistance and high optical transparency, a nitrogen-rich DOPO-based derivate (named as FATP) was synthesized and incorporated into EP. It showed that the incorporation of the FATP reduced the fire hazard of the EP, as demonstrated by the fact that the EP/4% FATP blends gained a UL-94 V-0 rating and an LOI value of 35%, with the lowest values of the THR (86.7 MJ/m2), the PHRR (1059.3 kW/m2), and the TSP (89.6 MJ/m2). The presence of the FATP also reduced the thermal stability and the crosslinking density whilst improving the curing reaction and the storage modulus of the EP/FATP blends. The TG-FTIR spectra showed that •HPO/•PO free radicals and some nonflammable gases (HN3 and NH3) were produced during the pyrolysis, and the characterization (SEM, Raman spectroscopy, and XPS) of char residues confirmed that the FATP facilitated the formation of continuous and compact carbon layers of greater graphitization degree. It was thus concluded that the FATP played the flame-retardant roles in both the gas and condensed phases. Furthermore, the FREPs kept almost identical transparency as the pristine EP, and mechanical properties were also slightly enhanced. The FREPs presented in this work show promising applications in the fields of advanced optical technology.

TRPM8 contributes to liver regeneration via mitochondrial energy metabolism mediated by PGC1α.

Impairment of liver regeneration leads to severe morbidity in acute and chronic severe liver disease. Transient receptor potential melastain 8 (TRPM8) is involved in a variety of processes, including temperature sensing, ion homeostasis, and cell proliferation. However, whether TRPM8 contributes to liver regeneration is still unclear. We assessed the effect and mechanism of TRPM8 in liver regeneration and hepatocyte proliferation in vivo and in vitro. In this study, we found that TRPM8 deficiency impairs liver regeneration in mice. Mechanistically, the results revealed that mitochondrial energy metabolism was attenuated in livers from TRPM8 knockout (KO) mice. Furthermore, we found that TRPM8 contributes to the proliferation of hepatocytes via PGC1α. Taken together, this study shows that TRPM8 contributes to liver regeneration in mice after hepatectomy. Genetic approaches and pharmacological approaches to regulate TRPM8 activity may be beneficial to the promotion of liver regeneration.

Unexpected Copper-Catalyzed Cascade Reaction of 1,6-Enynes with Sulfoxonium Ylides.

An unprecedented copper-catalyzed cascade reaction of 1,6-enynes with sulfoxonium ylides is reported, providing a series of structurally intriguing 2,3-disubstituted indolines bearing a conjugated dienone functionality at the 3-position in moderate to excellent yields with good chemo-, regio-, and diastereoselectivities under mild reaction conditions. Importantly, sulfoxonium-ylide-derived copper-carbene herein exhibits quite different reactivity from that of diazo copper-carbene. A rational mechanism, an initial ammonium ylide rather than allene formation, is proposed.

Copper-Catalyzed Cycloadditions of Diazo Compounds with Imidazolidines/Hexahydropyrimidines for the Syntheses of N-Heterocycles.

Reported herein are the unprecedented copper-catalyzed formal [n + 1]/[n + 3] (n = 5, 6) cycloadditions of diazo compounds with imidazolidines/hexahydropyrimidines, thus providing a general, economical, and efficient route to construct different sized (six- to nine-membered) diaza-heterocycles in moderate to excellent yields under mild reaction conditions. This strategy features the use of copper catalyst to accomplish such diverse annulations and the utilization of imidazolidines/hexahydropyrimidines as stable 1,5-/1,6-dipoles.

Exploring the Neuroprotective Mechanism of Curcumin Inhibition of Intestinal Inflammation against Parkinson's Disease Based on the Gut-Brain Axis.

Parkinson's disease (PD) is a chronic progressive neurodegenerative disease commonly seen in aged people, in which gastrointestinal dysfunction is the most common nonmotor symptom and the activation of the gut-brain axis by intestinal inflammation may contribute to the pathogenesis of PD. In a previous study, curcumin was considered neuroprotective in PD, and this neuroprotective mechanism may act by inhibiting intestinal inflammation. Therefore, the aim of this study was to evaluate the effect of curcumin on motor dysfunction and the loss of dopaminergic neurons in a PD mouse model, induced by N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) using open field test and pole test behavioral assessments and the immunofluorescence and Western blot methods. Moreover, the effects of curcumin on gastrointestinal dysfunction, gastric barrier function, pro-inflammatory cytokines, and the SIRT1/NRF2 pathway in intestinal tissues in a PD mouse model were assessed using fecal parameters and intestinal dynamics, immunofluorescence, ELISA, and Western blot. A motor impairment study of an MPTP-induced mouse group prior to treatment with curcumin had a lower total movement distance and a slow average speed, while there was no statistical difference in the curcumin group. After treatment with curcumin, the total movement distance and average speed improved, the tyrosine hydroxylase (TH) rate in the substantia nigra pars compacta (SNpc) and striatum were reduced, the pyroptosis of AIM2 and caspase-1 activations were inhibited, and intestinal inflammatory factors and intestinal inflammation were reduced. Curcumin improved gastrointestinal disorders and gastrointestinal barrier function in the MPTP-induced mice and reversed MPTP-induced motor dysfunction and dopaminergic neuron loss in mice. The above effects may be partly dependent on curcumin activation of the SIRT1/NRF2 pathway in the colon. This study provides a potential opportunity to develop new preventive measures and novel therapeutic approaches that could target the gut-brain axis in the context of PD and provide a new intervention in the treatment of Parkinson's disease.

[Clinical observation of arthroscopic single channel treatment of carpal tunnel syndrome with self-made instruments].

OBJECTIVE: To investigate the efficacy of self-made arthroscopic single channel in the treatment of carpal tunnel syndrome. METHODS: Sixty patients with primary carpal tunnel syndrome treated from January 2014 to December 2019 were divided into arthroscopic group and traditional open operation group. There were 30 cases in arthroscopic group, including 12 males and 18 females, aged (47.5±4.5) years and the course of disease was (6.6±4.2) months. There were 30 cases in the traditional operation group, including 10 males and 20 females, aged (48.5±3.5) years, and the course of disease was (5.6±4.4) months. Both groups were unilateral. According to the anatomy of wrist joint and the characteristics of transverse carpal ligament and arthroscopy, the instruments including cannula, inner heart and hook knife were designed. The patients in two groups were treated with decompression of transverse carpal ligament using arthroscopy combined with self-made instruments and traditional open sergery. The incision length, operation time, intraoperative bleeding, hospitalization cost, hospitalization time and recovery time of the two groups were observed and compared. Boston Carpal Tunnel Questionnaire (BCTQ) score was used to evaluate the clinical efficacy of arthroscopy combined with self made instruments in the treatment of carpal tunnel syndrome. RESULTS: Compared with the traditional group, the arthroscopic group had significant advantages in incision length, operation time, intraoperative bleeding and hospital stay, but the total cost of hospitalization was increased. The Boston score was significantly higher in the arthroscopic group than that in the traditional group at 1 month after operation, but not at 3 and 6 months after operation. CONCLUSION: Arthroscopy combined with self-made instruments in the treatment of carpal tunnel syndrome is more reliable, minimally invasive and simplified than open surgery, but the patients should be clearly diagnosed and appropriately selected before operation to achieve satisfactory clinical effect.

A photoluminescent thermometer made from a thermoresponsive tetranuclear gold complex and phosphor N630.

Reaction of [(3-bdppmapy)(AuCl)2] with NaHmba (3-bdppmapy = N,N'-bis-(diphenylphosphanylmethyl-3-aminopytidine, H2mba = 2-mercaptobenzoic acid) resulted in a new tetranuclear Au/P/S complex [(3-bdppmapy)2(AuHmba)3(AuCl)] (1). Upon excitation at 370 nm, 1 exhibited solid state, room temperature, green fluorescent emission (QY = 4.7%, τ = 2.58 ns) which was significantly enanced at lower temperatures due to strengthening of the Au-Au interaction. Different ratios of 1 with phosphor N630 in PMMA were used to make thermochromic photoluminescent films and fibres that could be fabricated into an optical thermometer sensitive over temperature ranges 80-300 K and 300-370 K.

miR-937-5p targets SOX17 to modulate breast cancer cell cycle and cell proliferation through the Wnt signaling pathway.

Breast cancer is one of the most frequent cancers in women and the globally leading cause of cancer-related deaths. Bioinformatics and experimental analyses found that miR-937-5p may play a proto-oncogenic role in breast cancer; however, the specific effects and the molecular mechanism need further investigation. GSEA-KEGG and GSEA-GO suggested that miR-937-5p might be related to cell cycle and DNA replication. The experimental data indicated that miR-937-5p inhibition significantly repressed the proliferation of breast carcinoma cells and elicited S-phase cell cycle arrest. Meanwhile, the protein levels of proliferating marker ki-67 and cell cycle regulators Cyclin A2, Cyclin B1, CDK1, and Cyclin D1 were also decreased by miR-937-5p inhibition. miR-937-5p could directly bind to and negatively regulate SOX17. SOX17 overexpression also significantly repressed the proliferation of breast carcinoma cells and elicited S-phase cell cycle arrest and decreased ki-67, ß-catenin, c-Myc, Cyclin A2, Cyclin B1, Cyclin D1, and CDK1 protein contents. More importantly, the effects of miR-937-5p were reversed by SOX17.

Comparison of targeted percutaneous vertebroplasty and traditional percutaneous vertebroplasty for the treatment of osteoporotic vertebral compression fractures in the elderly.

OBJECTIVE: To investigate the clinical effect of precise puncture and low-dose bone cement in percutaneous vertebroplasty (PVP). METHODS: Sixty patients with osteoporotic vertebral compression fracture (OVCFs) who were treated with PVP in our hospital from July 2018 to June 2019. These included patients were divided into group A (N = 30) and group B (N = 30). Group A has punctured to the fracture area accurately and injected with a small dose of bone cement, the group B was injected with a conventional dose of bone cement. The operation time, the amount of bone cement injection, the number of X-rays, the VAS scores, the leakage rate of bone cement, and the incidence of adjacent vertebral fractures were compared between the two groups. RESULT: The operation time, fluoroscopic times, and bone cement volume in group A are less than that in group B (P < 0.05). Patients in group A had a lower incidence of cement leakage and adjacent vertebral fracture than that in patients in group B. There was no significant difference in postoperative pain relief between the two groups. CONCLUSIONS: Precise puncture and injection of small doses of bone cement can reduce the number of X-ray fluoroscopy, operation time, amount of bone cement injection, reduce the rate of bone cement leakage and the incidence of adjacent vertebral fractures, which is a safe and effective surgical approach for the treatment for the aged with OVCFs.

Role of Androgen in Liver Fat Content in Women: Metabolically Advantageous or Disadvantageous?

OBJECTIVE: Androgens have a controversial effect on liver fat content (LFC) in androgen-excess females and androgen-deficient males. Polycystic ovarian syndrome (PCOS) is often associated with hyperandrogenism and nonalcoholic fatty liver disease. The aim of this study was to explore the association between hyperandrogenemia and increased liver fat content in women with PCOS, independent of other metabolic parameters. METHODS: This case series study included 501 women with PCOS and 112 aged-matched controls in the outpatient department of a tertiary hospital. Anthropometric measurements, hepatic and renal function, glucose and lipid metabolism parameters, and sex hormones were examined in these women. LFC was measured by quantitative ultrasonography. RESULTS: Women with hyperandrogenism (P<.001), an oligomenorrhoea/anovulation phenotype (P = .0064), and a diagnosis of PCOS (P<.001) had higher LFC. Androgen level is an important factor among the 9 independent risk factors of LFC (P = .0239) and may have a dimorphic impact on LFC. In all women, when the free androgen index (FAI) was less than 41.94, LFC increased with the elevated FAI; when the FAI was greater than 41.94, LFC decreased with the elevated FAI (P<.001). In women with PCOS, receiver operating characteristic curve analysis demonstrated that LFC could at least partially predict impaired glucose regulation, impaired lipid metabolism, and insulin resistance (P<.0001 for all). CONCLUSION: Androgen level is associated with LFC in dimorphic directions. LFC may be a predictive factor of insulin resistance, impaired glucose regulation, and impaired lipid metabolism in women with PCOS.

Blood lead levels among Chinese children: The shifting influence of industry, traffic, and e-waste over three decades.

In China, data relating to the historic prevalence of childhood lead poisoning suggest its pervasiveness. This review analysed published epidemiological data on blood lead levels (BLLs) of 735,271 Chinese children aged 0-6 between 1987 and 2017. Among these children, the geometric mean (GM) BLL was 95.1 µg/L (geometric SD = 1.62), and 24.1% suffered lead poisoning (BLL ≥ 100 µg/L). Importantly, there was a temporal decrease in the GM BLL value, from 182.9 µg/L in 1987-1991 to 42.4 µg/L in 2012-2017. However, a rebound was seen in the most recent two years (2016 and 2017). Moreover, the GM BLL among Chinese children has not fallen as low as U.S. children. This indicates that either (1) leaded petrol or lead based-paint exposure sources have not been adequately controlled in China, or (2) other pollution sources, such as industry, traffic, and e-waste, are impacting Chinese children. Drivers behind spatio-temporal variations were explored to provide scientific evidence regarding the prevention of childhood lead poisoning. We found that BLLs among children in the central and eastern areas of China have dropped lower than those in the western area, and that the GM BLL of children living in rural areas now exceeds children in urban areas. These reversals may be associated with the industrial decentralization policy of the late 1980s, when many heavily polluting industries and manufacturers moved away from cities on the east coast. It was discovered that the BLLs of children living in areas associated with mining have remained high (GM BLL = 155.0 µg/L for 2007-2017), and that the lead poisoning rate (LPR) has become exceptionally high in areas associated with e-waste. Finally, the review offers a data comparison with other countries, an overview of potentially influencing factors and sources, as well as some suggested prevention strategies to reduce childhood lead exposure.

Characterization and T-DNA insertion sites identification of a multiple-branches mutant br in Betula platyphylla × Betula pendula.

BACKGROUND: Plant architecture, which is mostly determined by shoot branching, plays an important role in plant growth and development. Thus, it is essential to explore the regulatory molecular mechanism of branching patterns based on the economic and ecological importance. In our previous work, a multiple-branches birch mutant br was identified from 19 CINNAMOYL-COENZYME A REDUCTASE 1 (CCR1)-overexpressed transgenic lines, and the expression patterns of differentially expressed genes in br were analyzed. In this study, we further explored some other characteristics of br, including plant architecture, wood properties, photosynthetic characteristics, and IAA and Zeatin contents. Meanwhile, the T-DNA insertion sites caused by the insertion of exogenous BpCCR1 in br were identified to explain the causes of the mutation phenotypes. RESULTS: The mutant br exhibited slower growth, more abundant and weaker branches, and lower wood basic density and lignin content than BpCCR1 transgenic line (OE2) and wild type (WT). Compared to WT and OE2, br had high stomatal conductance (Gs), transpiration rate (Tr), but a low non-photochemical quenching coefficient (NPQ) and chlorophyll content. In addition, br displayed an equal IAA and Zeatin content ratio of main branches' apical buds to lateral branches' apical buds and high ratio of Zeatin to IAA content. Two T-DNA insertion sites caused by the insertion of exogenous BpCCR1 in br genome were found. On one site, chromosome 2 (Chr2), no known gene was detected on the flanking sequence. The other site was on Chr5, with an insertion of 388 bp T-DNA sequence, resulting in deletion of 107 bp 5' untranslated region (UTR) and 264 bp coding sequence (CDS) on CORONATINE INSENSITIVE 1 (BpCOII). In comparison with OE2 and WT, BpCOI1 was down-regulated in br, and the sensitivity of br to Methyl Jasmonate (MeJA) was abnormal. CONCLUSIONS: Plant architecture, wood properties, photosynthetic characteristics, and IAA and Zeatin contents in main and lateral branches' apical buds changed in br over the study's time period. One T-DNA insertion was identified on the first exon of BpCOI1, which resulted in the reduction of BpCOI1 expression and abnormal perception to MeJA in br. These mutation phenotypes might be associated with a partial loss of BpCOI1 in birch.

Ribonucleoside triphosphates promote T7 DNA replication and the lysis of T7-Infected Escherichia coli.

rNTPs are structurally similar to dNTPs, but their concentrations are much higher than those of dNTPs in cells. rNTPs in solutions or rNMP at the primer terminus or embedded in template always inhibit or block DNA replication, due to the reduced Mg2+ apparent concentration, competition of rNTPs with dNTPs, and the extra repulsive interaction of rNTP or rNMP with polymerase active site. In this work, unexpectedly, we found rNTPs can promote T7 DNA replication with the maximal promotion at rNTPs/dNTPs concentration ratio of 20. This promotion was not due to the optimized Mg2+ apparent concentration or the direct incorporation of extra rNMPs into DNA. This promotion was dependent on the concentrations and types of rNTPs. Kinetic analysis showed that this promotion was originated from the increased fraction of polymerase-DNA productive complex and the accelerated DNA polymerization. Further evidence showed that more polymerase-DNA complex was formed and their binding affinity was also enhanced in the presence of extra rNTPs. Moreover, this promotion in T7 DNA replication also accelerated the lysis of T7-infected host Escherichia coli. This work discovered that rNTPs could promote DNA replication, completely different from the traditional concept that rNTPs always inhibit DNA replication.