Comparative transcriptome analysis reveals genes involved in trichome development and metabolism in tobacco.

BACKGROUND: The glandular trichomes of tobacco (Nicotiana tabacum) can efficiently produce secondary metabolites. They act as natural bioreactors, and their natural products function to protect plants against insect-pests and pathogens and are also components of industrial chemicals. To clarify the molecular mechanisms of tobacco glandular trichome development and secondary metabolic regulation, glandular trichomes and glandless trichomes, as well as other different developmental tissues, were used for RNA sequencing and analysis. RESULTS: By comparing glandless and glandular trichomes with other tissues, we obtained differentially expressed genes. They were obviously enriched in KEGG pathways, such as cutin, suberine, and wax biosynthesis, flavonoid and isoflavonoid biosynthesis, terpenoid biosynthesis, and plant-pathogen interaction. In particular, the expression levels of genes related to the terpenoid, flavonoid, and wax biosynthesis pathway mainly showed down-regulation in glandless trichomes, implying that they lack the capability to synthesize certain exudate compounds. Among the differentially expressed genes, 234 transcription factors were found, including AP2-ERFs, MYBs, bHLHs, WRKYs, Homeoboxes (HD-ZIP), and C2H2-ZFs. These transcription factor and genes that highly expressed in trichomes or specially expressed in GT or GLT. Following the overexpression of R2R3-MYB transcription factor Nitab4.5_0011760g0030.1 in tobacco, an increase in the number of branched glandular trichomes was observed. CONCLUSIONS: Our data provide comprehensive gene expression information at the transcriptional level and an understanding of the regulatory pathways involved in glandular trichome development and secondary metabolism.

Cell-type specific inference from bulk RNA-sequencing data by integrating single cell reference profiles via EPIC-unmix.

Cell type specific (CTS) analysis is essential to reveal biological insights obscured in bulk tissue data. However, single-cell (sc) or single-nuclei (sn) resolution data are still cost-prohibitive for large-scale samples. Thus, computational methods to perform deconvolution from bulk tissue data are highly valuable. We here present EPIC-unmix, a novel two-step empirical Bayesian method integrating reference sc/sn RNA-seq data and bulk RNA-seq data from target samples to enhance the accuracy of CTS inference. We demonstrate through comprehensive simulations across three tissues that EPIC-unmix achieved 4.6% - 109.8% higher accuracy compared to alternative methods. By applying EPIC-unmix to human bulk brain RNA-seq data from the ROSMAP and MSBB cohorts, we identified multiple genes differentially expressed between Alzheimer's disease (AD) cases versus controls in a CTS manner, including 57.4% novel genes not identified using similar sample size sc/snRNA-seq data, indicating the power of our in-silico approach. Among the 6-69% overlapping, 83%-100% are in consistent direction with those from sc/snRNA-seq data, supporting the reliability of our findings. EPIC-unmix inferred CTS expression profiles similarly empowers CTS eQTL analysis. Among the novel eQTLs, we highlight a microglia eQTL for AD risk gene AP3B2, obscured in bulk and missed by sc/snRNA-seq based eQTL analysis. The variant resides in a microglia-specific cCRE, forming chromatin loop with AP3B2 promoter region in microglia. Taken together, we believe EPIC-unmix will be a valuable tool to enable more powerful CTS analysis.

EndoPRS: Incorporating Endophenotype Information to Improve Polygenic Risk Scores for Clinical Endpoints.

Polygenic risk score (PRS) prediction of complex diseases can be improved by leveraging related phenotypes. This has motivated the development of several multi-trait PRS methods that jointly model information from genetically correlated traits. However, these methods do not account for vertical pleiotropy between traits, in which one trait acts as a mediator for another. Here, we introduce endoPRS, a weighted lasso model that incorporates information from relevant endophenotypes to improve disease risk prediction without making assumptions about the genetic architecture underlying the endophenotype-disease relationship. Through extensive simulation analysis, we demonstrate the robustness of endoPRS in a variety of complex genetic frameworks. We also apply endoPRS to predict the risk of childhood onset asthma in UK Biobank by leveraging a paired GWAS of eosinophil count, a relevant endophenotype. We find that endoPRS significantly improves prediction compared to many existing PRS methods, including multi-trait PRS methods, MTAG and wMT-BLUP, which suggests advantages of endoPRS in real-life clinical settings.

Measurements of 131I activity in thyroid of workers at the place of radioiodine therapy in 38 hospitals in China.

To investigate the levels of 131I activity in thyroid of workers at the place of radioiodine therapy and their main influential factors in China, 341 workers at 38 hospitals performing radioiodine therapy procedure in five provinces were recruited to be measured in 2021. A hand-held gamma spectrometer with NaI(Tl) probe was plastered to the thyroids and thighs of the subjects during the measurement, and each measurement time was 120 s. The internal exposure dose was calculated, and the committed effective dose was estimated. In 86 (25.22%) of the 341 examined workers, 131I thyroid activity was above minimum detectable activity (MDA, 26.6 Bq). The maximum activity was 4.9 × 103 Bq. The detection results above MDA were at 22 (57.89%) different hospitals. The detectable rate for private hospitals (4.8%) was significantly lower than that for public hospitals (26.6%), P < 0.05. The detectable rate for hospitals in provincial capital cities (15.4%) was significantly lower than in nonprovincial capital cities (41.7%), P < 0.001. The detectable rate for hospitals engaged in 131I therapy for thyroid cancer (31.2%) was significantly higher than only for hyperthyroidism (10.3%), P < 0.001. A total of 32 subjects' committed effective dose might exceed 1 mSv. Results indicated the 131I activity in the thyroid of workers at the place of radioiodine varied considerably in China, and mainly related to ownership, location and therapy program of the hospitals.

CsERF003 enhanced peel coloration by promoting both chlorophyll degradation and carotenoid accumulation in citrus.

Uneven coloration is a common phenomenon in citrus fruit during the ripening stage, as affects the appearance and economic value of the fruit. The elevated expression of CsERF003 during the degreening process of both lemon and satsuma mandarin peels was reported. In this research, a similar performance of CsERF003 in the pericarp coloration process was also identified by transcriptome analysis of 'Fengjie 72-1' navel orange and Lane Late navel orange. However, the regulatory mechanism of CsERF003 is not clear yet. Overexpression of CsERF003 could deepen the color of citrus callus and promote peel degreening of Newhall navel orange, which was attributed to the upregulation of genes involved in chlorophyll degradation and carotenoid synthesis. Furthermore, CsERF003 acted as an activator to promote the expression of CsLCYE, but couldn't activate the expression of CsLCYB1 and CsLCYB2; CsERF003 could also bind to the promoter of CsSGR to activate its expression. Together, our findings shed light on the regulatory mechanism of CsERF003 in chlorophyll degradation and carotenoid accumulation, particularly in the α-branch of carotenoid metabolism. These insights offer valuable perspectives for the genetic enhancement of peel coloration in citrus.

Mechanism of action of Sambucus williamsii Hance var. miquelii in the treatment of osteoporosis analyzed by UHPLC-HRMS/MS combined network pharmacology and experimental validation.

Sambucus williamsii Hance var. miquelii(SWH) is a precious wild Chinese herb whose fruit, rhizome, leaves and root bark can be used as medicine. Sambucus Linn has pharmacological effects such as anti-osteoporosis, promoting fracture healing, anti-viral and anti-inflammatory. In this study, the main chemical components of the alcoholic extracts from SWH were rapidly identified by ultra-high performance liquid chromatography-quadrupole orbit trap high-resolution mass spectrometry (UHPLC- HRMS MS), and a total of 42 compounds were characterized from the alcoholic extracts of SWH. The results of network pharmacological validation showed that kaempferol, quercetin, luteolin, isorhamnetin and morroniside were the main active components, and KEGG enrichment demonstrated that SWH mainly affected the signaling pathways such as PI3K-Akt, TNF and FoxO by modulating the related targets such as AKT1, PIK3R1, EGFR, RELA SRC and PTGS2. The molecular docking results showed binding solid activity between the main active components of SWH and the targets. The network pharmacology was validated by establishing an animal model of osteoporosis (OP) in rats by gavage administration of vitamin A acid. The results of the pharmacological experiments showed that SWH could improve the degree of bone loss in the femur of osteoporotic rats, increase the number of trabeculae and decrease trabeculae porosity, up-regulate the Ca and P content in the serum of OP rats, down-regulate the scope of ALP and BGP in the serum, and promote the calcification of the bone matrix, and then exert the anti-OP efficacy. In this study, network pharmacology and pharmacological experiments verified the pharmacological mechanism of SWH in anti-OP rats. This provides a theoretical basis for the research and development of anti-OP drugs and a reference for the application of other traditional Chinese medicines in treating OP diseases.

TRIM21-mediated ubiquitylation of TAT suppresses liver metastasis in gallbladder cancer.

Liver metastasis is common in patients with gallbladder cancer (GBC), imposing a significant challenge in clinical management and serving as a poor prognostic indicator. However, the mechanisms underlying liver metastasis remain largely unknown. Here, we report a crucial role of tyrosine aminotransferase (TAT) in liver metastasis of GBC. TAT is frequently up-regulated in GBC tissues. Increased TAT expression is associated with frequent liver metastasis and poor prognosis of GBC patients. Overexpression of TAT promotes GBC cell migration and invasion in vitro, as well as liver metastasis in vivo. TAT knockdown has the opposite effects. Intriguingly, TAT promotes liver metastasis of GBC by potentiating cardiolipin-dependent mitophagy. Mechanistically, TAT directly binds to cardiolipin and leads to cardiolipin externalization and subsequent mitophagy. Moreover, TRIM21 (Tripartite Motif Containing 21), an E3 ubiquitin ligase, interacts with TAT. The histine residues 336 and 338 at TRIM21 are essential for this binding. TRIM21 preferentially adds the lysine 63 (K63)-linked ubiquitin chains on TAT principally at K136. TRIM21-mediated TAT ubiquitination impairs its dimerization and mitochondrial location, subsequently inhibiting tumor invasion and migration of GBC cells. Therefore, our study identifies TAT as a novel driver of GBC liver metastasis, emphasizing its potential as a therapeutic target.

Genetic variant rs1205 is associated with COVID-19 outcomes: The Strong Heart Study and Strong Heart Family Study.

BACKGROUND: Although COVID-19 infection has been associated with a number of clinical and environmental risk factors, host genetic variation has also been associated with the incidence and morbidity of infection. The CRP gene codes for a critical component of the innate immune system and CRP variants have been reported associated with infectious disease and vaccination outcomes. We investigated possible associations between COVID-19 outcome and a limited number of candidate gene variants including rs1205. METHODOLOGY/PRINCIPAL FINDINGS: The Strong Heart and Strong Heart Family studies have accumulated detailed genetic, cardiovascular risk and event data in geographically dispersed American Indian communities since 1988. Genotypic data and 91 COVID-19 adjudicated deaths or hospitalizations from 2/1/20 through 3/1/23 were identified among 3,780 participants in two subsets. Among 21 candidate variants including genes in the interferon response pathway, APOE, TMPRSS2, TLR3, the HLA complex and the ABO blood group, only rs1205, a 3' untranslated region variant in the CRP gene, showed nominally significant association in T-dominant model analyses (odds ratio 1.859, 95%CI 1.001-3.453, p = 0.049) after adjustment for age, sex, center, body mass index, and a history of cardiovascular disease. Within the younger subset, association with the rs1205 T-Dom genotype was stronger, both in the same adjusted logistic model and in the SOLAR analysis also adjusting for other genetic relatedness. CONCLUSION: A T-dominant genotype of rs1205 in the CRP gene is associated with COVID-19 death or hospitalization, even after adjustment for relevant clinical factors and potential participant relatedness. Additional study of other populations and genetic variants of this gene are warranted.

MagicalRsq-X: A cross-cohort transferable genotype imputation quality metric.

Since genotype imputation was introduced, researchers have been relying on the estimated imputation quality from imputation software to perform post-imputation quality control (QC). However, this quality estimate (denoted as Rsq) performs less well for lower-frequency variants. We recently published MagicalRsq, a machine-learning-based imputation quality calibration, which leverages additional typed markers from the same cohort and outperforms Rsq as a QC metric. In this work, we extended the original MagicalRsq to allow cross-cohort model training and named the new model MagicalRsq-X. We removed the cohort-specific estimated minor allele frequency and included linkage disequilibrium scores and recombination rates as additional features. Leveraging whole-genome sequencing data from TOPMed, specifically participants in the BioMe, JHS, WHI, and MESA studies, we performed comprehensive cross-cohort evaluations for predominantly European and African ancestral individuals based on their inferred global ancestry with the 1000 Genomes and Human Genome Diversity Project data as reference. Our results suggest MagicalRsq-X outperforms Rsq in almost every setting, with 7.3%-14.4% improvement in squared Pearson correlation with true R2, corresponding to 85-218 K variant gains. We further developed a metric to quantify the genetic distances of a target cohort relative to a reference cohort and showed that such metric largely explained the performance of MagicalRsq-X models. Finally, we found MagicalRsq-X saved up to 53 known genome-wide significant variants in one of the largest blood cell trait GWASs that would be missed using the original Rsq for QC. In conclusion, MagicalRsq-X shows superiority for post-imputation QC and benefits genetic studies by distinguishing well and poorly imputed lower-frequency variants.

The BTB-BACK-TAZ domain protein MdBT2 reduces drought resistance by weakening the positive regulatory effect of MdHDZ27 on apple drought tolerance via ubiquitination.

Drought stress is one of the dominating challenges to the growth and productivity in crop plants. Elucidating the molecular mechanisms of plants responses to drought stress is fundamental to improve fruit quality. However, such molecular mechanisms are poorly understood in apple (Malus domestica Borkh.). In this study, we explored that the BTB-BACK-TAZ protein, MdBT2, negatively modulates the drought tolerance of apple plantlets. Moreover, we identified a novel Homeodomain-leucine zipper (HD-Zip) transcription factor, MdHDZ27, using a yeast two-hybrid (Y2H) screen with MdBT2 as the bait. Overexpression of MdHDZ27 in apple plantlets, calli, and tomato plantlets enhanced their drought tolerance by promoting the expression of drought tolerance-related genes [responsive to dehydration 29A (MdRD29A) and MdRD29B]. Biochemical analyses demonstrated that MdHDZ27 directly binds to and activates the promoters of MdRD29A and MdRD29B. Furthermore, in vitro and in vivo assays indicate that MdBT2 interacts with and ubiquitinates MdHDZ27, via the ubiquitin/26S proteasome pathway. This ubiquitination results in the degradation of MdHDZ27 and weakens the transcriptional activation of MdHDZ27 on MdRD29A and MdRD29B. Finally, a series of transgenic analyses in apple plantlets further clarified the role of the relationship between MdBT2 and MdHDZ27, as well as the effect of their interaction on drought resistance in apple plantlets. Collectively, our findings reveal a novel mechanism by which the MdBT2-MdHDZ27 regulatory module controls drought tolerance, which is of great significance for enhancing the drought resistance of apple and other plants.

ROS-Induced Gingival Fibroblast Senescence: Implications in Exacerbating Inflammatory Responses in Periodontal Disease.

Periodontal disease is the pathological outcome of the overwhelming inflammation in periodontal tissue. Cellular senescence has been associated with chronic inflammation in several diseases. However, the role of cellular senescence in the pathogenesis of periodontal disease remained unclear. This study aimed to investigate the role and the mechanism of cellular senescence in periodontal disease. Using single-cell RNA sequencing, we first found the upregulated level of cellular senescence in fibroblasts and endothelial cells from inflamed gingival tissue. Subsequently, human gingival fibroblasts isolated from healthy and inflamed gingival tissues were labeled as H-GFs and I-GFs, respectively. Compared to H-GFs, I-GFs exhibited a distinct cellular senescence phenotype, including an increased proportion of senescence-associated ß-galactosidase (SA-ß-gal) positive cells, enlarged cell morphology, and significant upregulation of p16INK4A expression. We further observed increased cellular reactive oxygen species (ROS) activity, mitochondrial ROS, and DNA damage of I-GFs. These phenotypes could be reversed by ROS scavenger NAC, which suggested the cause of cellular senescence in I-GFs. The migration and proliferation assay showed the decreased activity of I-GFs while the gene expression of senescence-associated secretory phenotype (SASP) factors such as IL-1ß, IL-6, TGF-ß, and IL-8 was all significantly increased. Finally, we found that supernatants of I-GF culture induced more neutrophil extracellular trap (NET) formation and drove macrophage polarization toward the CD86-positive M1 pro-inflammatory phenotype. Altogether, our findings implicate that, in the inflamed gingiva, human gingival fibroblasts acquire a senescent phenotype due to oxidative stress-induced DNA and mitochondrial damage, which in turn activate neutrophils and macrophages through the secretion of SASP factors.

Admix-kit: an integrated toolkit and pipeline for genetic analyses of admixed populations.

SUMMARY: Admixed populations, with their unique and diverse genetic backgrounds, are often underrepresented in genetic studies. This oversight not only limits our understanding but also exacerbates existing health disparities. One major barrier has been the lack of efficient tools tailored for the special challenges of genetic studies of admixed populations. Here, we present admix-kit, an integrated toolkit and pipeline for genetic analyses of admixed populations. Admix-kit implements a suite of methods to facilitate genotype and phenotype simulation, association testing, genetic architecture inference, and polygenic scoring in admixed populations. AVAILABILITY AND IMPLEMENTATION: Admix-kit package is open-source and available at https://github.com/KangchengHou/admix-kit. Additionally, users can use the pipeline designed for admixed genotype simulation available at https://github.com/UW-GAC/admix-kit_workflow.

A Large-Scale Genome-Wide Study of Gene-Sleep Duration Interactions for Blood Pressure in 811,405 Individuals from Diverse Populations.

Although both short and long sleep duration are associated with elevated hypertension risk, our understanding of their interplay with biological pathways governing blood pressure remains limited. To address this, we carried out genome-wide cross-population gene-by-short-sleep and long-sleep duration interaction analyses for three blood pressure traits (systolic, diastolic, and pulse pressure) in 811,405 individuals from diverse population groups. We discover 22 novel gene-sleep duration interaction loci for blood pressure, mapped to genes involved in neurological, thyroidal, bone metabolism, and hematopoietic pathways. Non-overlap between short sleep (12) and long sleep (10) interactions underscores the plausibility of distinct influences of both sleep duration extremes in cardiovascular health. With several of our loci reflecting specificity towards population background or sex, our discovery sheds light on the importance of embracing granularity when addressing heterogeneity entangled in gene-environment interactions, and in therapeutic design approaches for blood pressure management.

Immediate versus Non-immediate Loading Protocols for Reduced-diameter Implants Supporting Overdentures: A Systematic Review and Meta-analysis.

OBJECTIVE: This systematic review aimed to compare the influence of immediate and non-immediate loading protocols on overdentures retained by reduced-diameter implants(≦3.5mm). METHODS: Electronic databases, including MEDLINE (via PubMed), Embase and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) comparing clinical outcomes of immediately and nonimmediately loaded reduced-diameter implants supported overdentures. The risk of bias within and across the studies and the certainty of evidence were assessed by RoB 2.0 and GRADE, respectively. Sensitivity analysis was performed by eliminating studies at high risk of bias, and repeating the data synthesis employing the randomeffect model. Subgroup analyses were conducted based on the implant diameter and the length of follow-up. RESULTS: Six RCTs with 255 patients were included in this systematic review. The meta-analyses found similar implant survival rates between immediate and nonimmediate loaded implants in mini implant (RR=0.98; 95% CI=0.95, 1.01; p=0.12) and narrow implant subgroups (RR=0.99, 95% CI=0.94, 1.03, p =0.56), as well as in short-term (RR=0.98, 95% CI=0.97, 1.00, p =0.11) and long-term (RR=0.97, 95% CI=0.93, 1.01, p =0.09) follow-up subgroups. Additionally, marginal bone loss (MBL) showed no statistically significant difference between the loading protocols in the subgroup of long-term follow-up (MD=0.03; 95%CI=-0.16, 0.23; p=0.74). Three RCTs investigating peri-implant parameters found relatively higher modified plaque index and probing depth in reduced-diameter implant under immediate loading. CONCLUSION: Compared with non-immediate loading, the immediately loading protocol can achieve comparable survival rates and MBL in reduced-diameter implant retained overdentures.

Cost-effectiveness analysis of Tislelizumab vs Sorafenib as the first-line treatment of unresectable hepatocellular carcinoma.

BACKGROUND: To evaluate the cost-effectiveness of Tislelizumab vs Sorafenib as the first-line treatment of unresectable hepatocellular carcinoma (HCC) from the perspective of the Chinese health service system. METHODS: A lifetime partitioned survival model (PSM) was developed to cost-effectively analyze Tislelizumab vs Sorafenib as the first-line treatment of unresectable HCC. The clinical and safety data were derived from a recently randomized clinical trial (RATIONALE-301). Utilities were collected from the published literature. Costs were obtained from an open-access database (http://www.yaozh.com) and previous studies. The model cycle was 21 days, according to the RATIONALE-301 study, and the simulation period was patients' lifetime. Long-term direct medical costs and quality-adjusted life-years (QALYs) were determined. The incremental cost-effectiveness ratio (ICER) was used as the evaluation index. one-way sensitivity analysis (OSWA) and probabilistic sensitivity analysis (PSA) were used to analyze the uncertainty of parameters and to adjust and verify the stability of the baseline results. RESULTS: The Tislelizumab group generated a cost of $39,746.34 and brought health benefits to 2.146 QALYs, while the cost and utility of the Sorafenib group were $26750.95 and 1.578 QALYs, respectively. The Tislelizumab group increased QALYs by 0.568, the incremental cost was $12995.39, and the ICER was $22869.64/QALY, lower than the willingness to pay threshold (WTP). OSWA results showed that the utility of progressed disease (PD), cost of Camrelizumab, and cost of Tislelizumab were the main factors affecting the ICER. PSA results showed that, within 1000 times the Monte Carlo simulation, the cost of the Tislelizumab group was lower than three times the per capita gross domestic product (GDP) of China ($37653/QALY). The cost-effectiveness acceptability curves (CEAC) revealed that when WTP was no less than $12251.00, the Tislelizumab group was the dominant scheme, and the economic advantage grew with an increasing WTP. When WTP ≥ $19000.00, the Tislelizumab group became the absolute economic advantage. CONCLUSION: Under the current economic conditions in China, the Tislelizumab therapeutic scheme is more cost-effective than the Sorafenib therapeutic scheme for treating patients with unresectable HCC.

Efficacy and Safety of Hepatic Arterial Infusion Therapy with Cinobufacini in Advanced Hepatocellular Carcinoma with Macrovascular Invasion: A Retrospective Cohort Study.

Background: The presence of macrovascular invasion (MVI) is associated with poor prognosis in advanced hepatocellular carcinoma (HCC). This study aims to evaluate the efficacy and safety of Cinobufacini therapy via hepatic arterial infusion (HAI) in advanced HCC patients with MVI. Methods: The clinical records of 130 consecutive patients with unresectable advanced HCC and MVI who had received Cinobufacini or cisplatin plus 5-fluorouracil (CF) treatment via HAI were retrospectively analyzed. The therapeutic efficacy, overall survival (OS), progression-free survival (PFS), and adverse events were compared between the two treatment groups. Results: The Cinobufacini group demonstrated significant curative effects on treatment via HAI compared with the CF group, including the objective response rate (44.9% vs 27.9%, P=0.048), the median OS (14.8 months vs 11.1 months, P=0.010), and the median PFS (10.3 months vs 6.0 months, P=0.006). Result in subgroup analysis of portal vein invasion grade supported the efficacy in Cinobufacini treatment, especially in the median OS of Vp1-2 (18.3 months vs 14.3 months, P=0.043) and Vp3 (15.0 months vs 11.4 months, P=0.046), as well as the median PFS of Vp1-2 (14.8 months vs 10.2 months, P=0.028) and Vp3 (10.8 months vs 6.6 months, P=0.033) compared with CF treatment. Cox proportional hazards model and forest plot analysis of factors confirmed the survival benefit from HAI with Cinobufacini over CF (hazard ratio [HR], 0.61; 95% CI: 0.40-0.91; P=0.010). Multivariable analysis identified portal vein invasion grade (Vp4; HR, 1.78; 95% CI: 1.03-2.16; P=0.032) and AFP (>1000; HR, 1.61; 95% CI: 1.08-1.91; P=0.039) as the independent factors for prognosis. Moreover, the total incidence of adverse events in the Cinobufacini group was significantly lower than in the CF group (60.9% vs 82.0%, P=0.009). Conclusion: Cinobufacini therapy via HAI is a viable strategy for curing advanced HCC with MVI, due to prolonged survival and a superior safety profile.

MdPRX34L, a class III peroxidase gene, activates the immune response in apple to the fungal pathogen Botryosphaeria dothidea.

MAIN CONCLUSION: MdPRX34L enhanced resistance to Botryosphaeria dothidea by increasing salicylic acid (SA) and abscisic acid (ABA) content as well as the expression of related defense genes. The class III peroxidase (PRX) multigene family is involved in complex biological processes. However, the molecular mechanism of PRXs in the pathogen defense of plants against Botryosphaeria dothidea (B. dothidea) remains unclear. Here, we cloned the PRX gene MdPRX34L, which was identified as a positive regulator of the defense response to B. dothidea, from the apple cultivar 'Royal Gala.' Overexpression of MdPRX34L in apple calli decreased sensitivity to salicylic acid (SA) and abscisic acid（ABA). Subsequently, overexpression of MdPRX34L in apple calli increased resistance to B. dothidea infection. In addition, SA contents and the expression levels of genes related to SA synthesis and signaling in apple calli overexpressing MdPRX34L were higher than those in the control after inoculation, suggesting that MdPRX34L enhances resistance to B. dothidea via the SA pathway. Interestingly, infections in apple calli by B. dothidea caused an increase in endogenous levels of ABA followed by induction of ABA-related genes expression. These findings suggest a potential mechanism by which MdPRX34L enhances plant-pathogen defense against B. dothidea by regulating the SA and ABA pathways.

Tumour response following preoperative chemotherapy is affected by body mass index in patients with colorectal liver metastases.

BACKGROUND: Colorectal cancer is the third most prevalent malignancy globally and ranks second in cancer-related mortality, with the liver being the primary organ of metastasis. Preoperative chemotherapy is widely recommended for initially or potentially resectable colorectal liver metastases (CRLMs). Tumour pathological response serves as the most important and intuitive indicator for assessing the efficacy of chemotherapy. However, the postoperative pathological results reveal that a considerable number of patients exhibit a poor response to preoperative chemotherapy. Body mass index (BMI) is one of the factors affecting the tumorigenesis and progression of colorectal cancer as well as prognosis after various antitumour therapies. Several studies have indicated that overweight and obese patients with metastatic colorectal cancer experience worse prognoses than those with normal weight, particularly when receiving first-line chemotherapy regimens in combination with bevacizumab. AIM: To explore the predictive value of BMI regarding the pathologic response following preoperative chemotherapy for CRLMs. METHODS: A retrospective analysis was performed in 126 consecutive patients with CRLM who underwent hepatectomy following preoperative chemotherapy at four different hospitals from October 2019 to July 2023. Univariate and multivariate logistic regression models were applied to analyse potential predictors of tumour pathological response. The Kaplan-Meier method with log rank test was used to compare progression-free survival (PFS) between patients with high and low BMI. BMI < 24.0 kg/m2 was defined as low BMI, and tumour regression grade 1-2 was defined as complete tumour response. RESULTS: Low BMI was observed in 74 (58.7%) patients and complete tumour response was found in 27 (21.4%) patients. The rate of complete tumour response was significantly higher in patients with low BMI (29.7% vs 9.6%, P = 0.007). Multivariate analysis revealed that low BMI [odds ratio (OR) = 4.56, 95% confidence interval (CI): 1.42-14.63, P = 0.011], targeted therapy with bevacizumab (OR = 3.02, 95%CI: 1.10-8.33, P = 0.033), preoperative carcinoembryonic antigen level < 10 ng/mL (OR = 3.84, 95%CI: 1.19-12.44, P = 0.025) and severe sinusoidal dilatation (OR = 0.17, 95%CI: 0.03-0.90, P = 0.037) were independent predictive factors for complete tumour response. The low BMI group exhibited a significantly longer median PFS than the high BMI group (10.7 mo vs 4.7 mo, P = 0.011). CONCLUSION: In CRLM patients receiving preoperative chemotherapy, a low BMI may be associated with better tumour response and longer PFS.

Cytochrome P450 CitCYP97B modulates carotenoid accumulation diversity by hydroxylating ß-cryptoxanthin in Citrus.

Carotenoids in plant foods provide health benefits by functioning as provitamin A. One of the vital provitamin A carotenoids, ß-cryptoxanthin, is typically plentiful in citrus fruit. However, little is known about the genetic basis of ß-cryptoxanthin accumulation in citrus. Here, we performed a widely targeted metabolomic analysis of 65 major carotenoids and carotenoid derivatives to characterize carotenoid accumulation in Citrus and determine the taxonomic profile of ß-cryptoxanthin. We used data from 81 newly sequenced representative accessions and 69 previously sequenced Citrus cultivars to reveal the genetic basis of ß-cryptoxanthin accumulation through a genome-wide association study. We identified a causal gene, CitCYP97B, which encodes a cytochrome P450 protein whose substrate and metabolic pathways in land plants were undetermined. We subsequently demonstrated that CitCYP97B functions as a novel monooxygenase that specifically hydroxylates the ß-ring of ß-cryptoxanthin in a heterologous expression system. In planta experiments provided further evidence that CitCYP97B negatively regulates ß-cryptoxanthin content. Using the sequenced Citrus accessions, we found that two critical structural cis-element variations contribute to increased expression of CitCYP97B, thereby altering ß-cryptoxanthin accumulation in fruit. Hybridization/introgression appear to have contributed to the prevalence of two cis-element variations in different Citrus types during citrus evolution. Overall, these findings extend our understanding of the regulation and diversity of carotenoid metabolism in fruit crops and provide a genetic target for production of ß-cryptoxanthin-biofortified products.