Comprehensive understanding of glioblastoma molecular phenotypes:classification,characteristics,and transition

Among central nervous system-associated malignancies,glioblastoma(GBM)is the most common and has the highest mortality rate.The high heterogeneity of GBM cell types and the complex tumor microenvironment frequently lead to tumor recurrence and sudden relapse in patients treated with temozolomide.In precision medicine,research on GBM treatment is increasingly focusing on molecular subtyping to precisely characterize the cellular and molecular heterogeneity,as well as the refractory nature of GBM toward therapy.Deep understanding of the different molecular expression patterns of GBM subtypes is critical.Researchers have recently proposed tetra fractional or tripartite methods for detecting GBM molecular subtypes.The various molecular subtypes of GBM show significant differences in gene expression patterns and biological behaviors.These subtypes also exhibit high plasticity in their regulatory pathways,oncogene expression,tumor microenvironment alterations,and differential responses to standard therapy.Herein,we summarize the current molecular typing scheme of GBM and the major molecular/genetic characteristics of each subtype.Furthermore,we review the mesenchymal transition mechanisms of GBM under various regulators.

Analysis of Phenotypes Associated with Deficiency of PAX6 Haplotypes in Chinese Aniridia Families

Objective To examine the clinical phenotype and genetic deficiencies present in Chinese aniridia families with PAX6 haplotype deficiency.Methods A comprehensive questionnaire and ophthalmological assessments were administered to both affected patients and unaffected relatives.The clinical feature analysis included the evaluation of visual acuity,intraocular pressure,slit-lamp anterior segment examination,fundus photography,and spectral domain optical coherence tomography.To identify the mutation responsible for aniridia,targeted next-generation sequencing was used as a beneficial technique.Results A total of 4 mutations were identified,consisting of two novel frameshift mutations(c.314delA,p.K105Sfs*33 and c.838_845dup AACACACC,p.S283Tfs*85),along with two recurring nonsense mutations(c.307C>T,p.R103X and c.619A>T,p.K207*).Complete iris absence,macular foveal hypoplasia,and nystagmus were consistent in these PAX6 haplotype-deficient Chinese aniridia families,while corneal lesions,cataracts,and glaucoma exhibited heterogeneity both among the families and within the same family.Conclusion In our study,two novel PAX6 mutations associated with aniridia were identified in Chinese families,which expanded the phenotypic and genotypic spectrum of PAX6 mutations.We also analyzed the clinical characteristics of PAX6 haplotype deficiency in Chinese aniridia families.

Classification of congenital cataracts based on multidimensional phenotypes and its association with visual outcomes

●AIM:To establish a classification for congenital cataracts that can facilitate individualized treatment and help identify individuals with a high likelihood of different visual outcomes.●METHODS:Consecutive patients diagnosed with congenital cataracts and undergoing surgery between January 2005 and November 2021 were recruited.Data on visual outcomes and the phenotypic characteristics of ocular biometry and the anterior and posterior segments were extracted from the patients’medical records.A hierarchical cluster analysis was performed.The main outcome measure was the identification of distinct clusters of eyes with congenital cataracts.●RESULTS:A total of 164 children(299 eyes)were divided into two clusters based on their ocular features.Cluster 1(96 eyes)had a shorter axial length(mean±SD,19.44±1.68 mm),a low prevalence of macular abnormalities(1.04%),and no retinal abnormalities or posterior cataracts.Cluster 2(203 eyes)had a greater axial length(mean±SD,20.42±2.10 mm)and a higher prevalence of macular abnormalities(8.37%),retinal abnormalities(98.52%),and posterior cataracts(4.93%).Compared with the eyes in Cluster 2(57.14%),those in Cluster 1(71.88%)had a 2.2 times higher chance of good best-corrected visual acuity[<0.7 logMAR;OR(95%CI),2.20(1.25–3.81);P=0.006].●CONCLUSION:This retrospective study categorizes congenital cataracts into two distinct clusters,each associated with a different likelihood of visual outcomes.This innovative classification may enable the personalization and prioritization of early interventions for patients who may gain the greatest benefit,thereby making strides toward precision medicine in the field of congenital cataracts.

Chromosome-level genome assembly of the glass catfish(Kryptopterus vitreolus)reveals molecular clues to its transparent phenotype

Glass catfish(Kryptopterus vitreolus)are notable in the aquarium trade for their highly transparent body pattern.This transparency is due to the loss of most reflective iridophores and light-absorbing melanophores in the main body,although certain black and silver pigments remain in the face and head.To date,however,the molecular mechanisms underlying this transparent phenotype remain largely unknown.To explore the genetic basis of this transparency,we constructed a chromosome-level haplotypic genome assembly for the glass catfish,encompassing 32 chromosomes and 23344 protein-coding genes,using PacBio and Hi-C sequencing technologies and standard assembly and annotation pipelines.Analysis revealed a premature stop codon in the putative albinism-related tyrp1b gene,encoding tyrosinase-related protein 1,rendering it a nonfunctional pseudogene.Notably,a synteny comparison with over 30 other fish species identified the loss of the endothelin-3(edn3b)gene in the glass catfish genome.To investigate the role of edn3b,we generated edn3b^(−/−)mutant zebrafish,which exhibited a remarkable reduction in black pigments in body surface stripes compared to wild-type zebrafish.These findings indicate that edn3b loss contributes to the transparent phenotype of the glass catfish.Our high-quality chromosome-scale genome assembly and identification of key genes provide important molecular insights into the transparent phenotype of glass catfish.These findings not only enhance our understanding of the molecular mechanisms underlying transparency in glass catfish,but also offer a valuable genetic resource for further research on pigmentation in various animal species.

Identification of clinical subphenotypes of sepsis after laparoscopic surgery

Objective:Some patients exhibit septic symptoms following laparoscopic surgery,leading to a poor prognosis.Effective clinical subphenotyping is critical for guiding tailored therapeutic strategies in these cases.By identifying predisposing factors for postoperative sepsis,clinicians can implement targeted interventions,potentially improving outcomes.This study outlines a workflow for the subphenotype methodology in the context of laparoscopic surgery,along with its practical application.Methods:This study utilized data routinely available in clinical case systems,enhancing the applicability of our findings.The data included vital signs,such as respiratory rate,and laboratory measures,such as blood sodium levels.The process of categorizing clinical routine data involved technical complexities.A correlation heatmap was used to visually depict the relationships between variables.Ordering points were used to identify the clustering structure and combined with Consensus K clustering methods to determine the optimal categorization.Results:Our study highlighted the intricacies of identifying clinical subphenotypes following laparoscopic surgery,and could thus serve as a valuable resource for clinicians and researchers seeking to explore disease heterogeneity in clinical settings.By simplifying complex methodologies,we aimed to bridge the gap between technical expertise and clinical application,fostering an environment where professional medical knowledge is effectively utilized in subphenotyping research.Conclusion:This tutorial could primarily serve as a guide for beginners.A variety of clustering approaches were explored,and each step in the process contributed to a comprehensive understanding of clinical subphenotypes.

Causal association between 731 immunocyte phenotypes and liver cirrhosis: A bidirectional two-sample mendelian randomization analysis

BACKGROUND Liver cirrhosis is a progressive hepatic disease whose immunological basis has attracted increasing attention.However,it remains unclear whether a concrete causal association exists between immunocyte phenotypes and liver cirrhosis.AIM To explore the concrete causal relationships between immunocyte phenotypes and liver cirrhosis through a mendelian randomization(MR)study.METHODS Data on 731 immunocyte phenotypes were obtained from genome-wide assoc-iation studies.Liver cirrhosis data were derived from the Finn Gen dataset,which included 214403 individuals of European ancestry.We used inverse variable weighting as the primary analysis method to assess the causal relationship.Sensitivity analyses were conducted to evaluate heterogeneity and horizontal pleiotropy.RESULTS The MR analysis demonstrated that 11 immune cell phenotypes have a positive association with liver cirrhosis[P<0.05,odds ratio(OR)>1]and that 9 immu-nocyte phenotypes were negatively correlated with liver cirrhosis(P<0.05,OR<1).Liver cirrhosis was positively linked to 9 immune cell phenotypes(P<0.05,OR>1)and negatively linked to 10 immune cell phenotypes(P<0.05;OR<1).None of these associations showed heterogeneity or horizontally pleiotropy(P>0.05).CONCLUSION This bidirectional two-sample MR study demonstrated a concrete causal association between immunocyte phenotypes and liver cirrhosis.These findings offer new directions for the treatment of liver cirrhosis.

Association between the Different Phenotypes of Polycystic Ovary Syndrome and the Outcome in in Vitro Fertilization at Human Reproductive Center Paul et Chantal Biya-Yaoundé

Background: In Vitro Fertilization/Intracytoplasmic Sperm Injection (IVF/ICSI) represents the final step in the management of Polycystic Ovarian Syndrome (PCOS). Our objective was to study the association between PCOS phenotypes and IVF/ICSI results in women admitted to Gynaecological Endoscopic Surgery and Human Reproductive Teaching Hospital (CHRACERH). Material and Method: We carried out a cohort study with historical-prospective data collection over a period of seven years (January 2016 to March 2023) at Chracerh. PCOS patients were subdivided into 4 subgroups A, B, C and D. Results: We recruited 128 patients including 64 PCOS patients divided into four phenotypes and 64 non-PCOS patients constituting the control group. Phenotype D without hyperandrogenism had used the lowest dose of gonadotropins, i.e. 1939.7 ± 454.3 IU, and had produced a greater quantity of estradiol on the day ovulation was triggered (6529.8 ± 4324.8 ng/ml). The average number of punctured follicles and mature oocytes were higher in the phenotype D group. Ovarian hyperstimulation syndrome (OHSS) occurred mainly in phenotype D (3/35), with an estimated prevalence of 2.3%. The fertilization rate seemed lower in the hyperandrogenic phenotypes A, B, C compared to the group without hyperandrogenism without significant difference (p = 0.461). The biological pregnancy rate and live birth rate were comparable between the different groups. Conclusion: Phenotype D used less dose of gonadotropins. Biological pregnancy and live birth rates were comparable between the different phenotypes.

Mesenchymal stem cell-derived exosomes regulate microglia phenotypes:a promising treatment for acute central nervous system injury

There is growing evidence that long-term central nervous system(CNS)inflammation exacerbates secondary deterioration of brain structures and functions and is one of the major determinants of disease outcome and progression.In acute CNS injury,brain microglia are among the first cells to respond and play a critical role in neural repair and regeneration.However,microglial activation can also impede CNS repair and amplify tissue damage,and phenotypic transformation may be responsible for this dual role.Mesenchymal stem cell(MSC)-derived exosomes(Exos)are promising therapeutic agents for the treatment of acute CNS injuries due to their immunomodulatory and regenerative properties.MSC-Exos are nanoscale membrane vesicles that are actively released by cells and are used clinically as circulating biomarkers for disease diagnosis and prognosis.MSC-Exos can be neuroprotective in several acute CNS models,including for stroke and traumatic brain injury,showing great clinical potential.This review summarized the classification of acute CNS injury disorders and discussed the prominent role of microglial activation in acute CNS inflammation and the specific role of MSC-Exos in regulating pro-inflammatory microglia in neuroinflammatory repair following acute CNS injury.Finally,this review explored the potential mechanisms and factors associated with MSCExos in modulating the phenotypic balance of microglia,focusing on the interplay between CNS inflammation,the brain,and injury aspects,with an emphasis on potential strategies and therapeutic interventions for improving functional recovery from early CNS inflammation caused by acute CNS injury.

SPP-extractor:Automatic phenotype extraction for densely grown soybean plants

Automatic collecting of phenotypic information from plants has become a trend in breeding and smart agriculture.Targeting mature soybean plants at the harvesting stage,which are dense and overlapping,we have proposed the SPP-extractor(soybean plant phenotype extractor)algorithm to acquire phenotypic traits.First,to address the mutual occultation of pods,we augmented the standard YOLOv5s model for target detection with an additional attention mechanism.The resulting model could accurately identify pods and stems and could count the entire pod set of a plant in a single scan.Second,considering that mature branches are usually bent and covered with pods,we designed a branch recognition and measurement module combining image processing,target detection,semantic segmentation,and heuristic search.Experimental results on real plants showed that SPP-extractor achieved respective R^(2) scores of 0.93–0.99 for four phenotypic traits,based on regression on manual measurements.

LncRNA CACNA1G-AS1 up-regulates FTH1 to inhibit ferroptosis and promote malignant phenotypes in ovarian cancer cells

Previous study revealed that ferritin heavy chain-1(FTH1)could regulate ferritinophagy and affect intracellular Fe^(+)content in various tumors,while its N6-methyladenosine(m6A)RNA methylation was closely related the prognosis of ovarian cancer patients.However,little is known about the role of FTH1 m6A methylation in ovarian cancer(OC)and its possible action mechanisms.In this study we constructed FTH1 m6A methylation regulatory pathway(LncRNA CACNA1G-AS1/IGF2BP1)according to related bioinformatics analysis and research,through clinical sample detections we found that these pathway regulatory factors were significantly up-regulated in ovarian cancer tissues,and their expression levels were closely related to the malignant phenotype of ovarian cancer.In vitro cell experiments showed that LncRNA CACNA1G-AS1 could up-regulate FTH1 expression through IGF2BP1 axis,thus inhibited ferroptosis by regulating ferritinophagy,and finally promoted proliferation and migration in ovarian cancer cells.Tumor-bearing mice studies showed that the knock-down of LncRNA CACNA1G-AS1 could inhibited the tumorigenesis of ovarian cancer cells in vivo condition.Our results demonstrated that LncRNA CACNA1G-AS1 could promote the malignant phenotypes of ovarian cancer cells through FTH1-IGF2BP1 regulated ferroptosis.

Identification of tolerance to high density and lodging in short petiolate germplasm M657 and the effect of density on yield-related phenotypes of soybean

Soybean yield has traditionally been increased through high planting density,but investigating plant height and petiole traits to select for compact architecture,lodging resistance,and high yield varieties is an underexplored option for further improving yield.We compared the relationships between yield-related traits,lodging resistance,and petioleassociated phenotypes in the short petiole germplasm M657 with three control accessions during 2017–2018 in four locations in the Huang–Huai region,China.The results showed that M657 exhibited stable and high tolerance to high planting density and resistance to lodging,especially at the highest density(8×105 plants ha–1).The regression analysis indicated that a shorter petiole length was significantly associated with increased lodging resistance.The yield analysis showed that M657 achieved higher yields under higher densities,especially in the northern part of the Huang–Huai region.Among the varieties,there were markedly different responses to intra-and inter-row spacing designs with respect to both lodging and yield that were related to location and density.Lodging was positively correlated with planting density,plant height,petiole length,and number of effective branches,but negatively correlated with stem diameter,seed number per plant,and seed weight per plant.The yield of soybean was increased by appropriately increasing the planting density on the basis of the current soybean varieties in the Huang–Huai region.This study provides a valuable new germplasm resource for the introgression of compact architecture traits that are amenable to providing a high yield in high density planting systems,and it establishes a high-yield model of soybean in the Huang–Huai region.

Redefying the therapeutic strategies against cardiorenal morbidity and mortality:Patient phenotypes

Chronic kidney disease(CKD)patients face an unacceptably high morbidity and mortality,mainly from cardiovascular diseases.Diabetes mellitus,arterial hypertension and dyslipidemia are highly prevalent in CKD patients.Established therapeutic protocols for the treatment of diabetes mellitus,arterial hypertension,and dyslipidemia are not as effective in CKD patients as in the general population.The role of non-traditional risk factors(RF)has gained interest in the last decades.These entail the deranged clinical spectrum of secondary hyperparathyroidism involving vascular and valvular calcification,under the term“CKDmineral and bone disorder”(CKD-MBD),uremia per se,inflammation and oxidative stress.Each one of these non-traditional RF have been addressed in various study designs,but the results do not exhibit any applied clinical benefit for CKD-patients.The“crusade”against cardiorenal morbidity and mortality in CKD-patients is in some instances,derailed.We propose a therapeutic paradigm advancing from isolated treatment targets,as practiced today,to precision medicine involving patient phenotypes with distinct underlying pathophysiology.In this regard we propose two steps,based on current stratification management of corona virus disease-19 and sepsis.First,select patients who are expected to have a high mortality,i.e.,a prognostic enrichment.Second,select patients who are likely to respond to a specific therapy,i.e.,a predictive enrichment.

Coexistent alcohol-related cirrhosis and chronic pancreatitis have a comparable phenotype to either disease alone:A comparative retrospective analysis

BACKGROUND Alcohol use disorder is a prevalent disease in the United States.It is a well-demonstrated cause of recurrent and long-standing liver and pancreatic injury which can lead to alcohol-related liver cirrhosis(ALC)and chronic pancreatitis(ACP).ALC and ACP are associated with significant healthcare utilization,cost burden,and mortality.The prevalence of coexistent disease(CD)ranges widely in the literature and the intersection between ALC and ACP is inconsistently charac-terized.As such,the clinical profile of coexistent ALC and ACP remains poorly understood.We hypothesized that patients with CD have a worse phenotype when compared to single organ disease.AIM To compare the clinical profile and outcomes of patients with CD from those with ALC or ACP Only.METHODS In this retrospective comparative analysis,we reviewed international classi-fication of disease 9/10 codes and electronic health records of adult patients with verified ALC Only(n=135),ACP Only(n=87),and CD(n=133)who received care at UPMC Presbyterian-Shadyside Hospital.ALC was defined by histology,imaging or clinical evidence of cirrhosis or hepatic decompensation.ACP was defined by imaging findings of pancreatic calcifications,moderate-severe pancreatic duct dilatation,irregularity or atrophy.We compared demographics,pertinent clinical variables,healthcare utilization,and mortality for patients with CD with those who had single organ disease.RESULTS Compared to CD or ACP Only,patients with ALC Only were more likely to be older,Caucasian,have higher body mass index,and Hepatitis B or C infection.CD patients(vs ALC Only)were less likely to have imaging evidence of cirrhosis and portal hypertension despite possessing similar MELD-Na and Child C scores at the most recent contact.CD patients(vs ACP Only)were less likely to have acute or recurrent acute pancreatitis,diabetes mellitus,insulin use,oral pancreatic enzyme therapy,and need for endoscopic therapy or pancreatic surgery.The number of hospitalizations in patients with CD were similar to ACP Only but significantly higher than ALC Only.The overall mortality in patients with CD was similar to ALC Only but trended to be higher than ACP Only(P=0.10).CONCLUSION CD does not have a worse phenotype compared with single organ disease.The dominant phenotype in CD is similar to ALC Only which should be the focus in longitudinal follow-up.

What Impact on Phenotype for Patients with Karyotype 46, XX DSD SRY Positive at CHU Dantec in Senegal: About 5 Cases?

Background: In disorders of sexual differentiation, sexual development may not conform to the chromosomal structure, thus forming different types of abnormalities. Among these abnormalities is syndrome 46, XX DSD where most patients are female phenotype with clitoral hypertrophy that can go to complete masculinization especially in the presence of the SRY gene. Objective: The goal of this work is to demonstrate a relationship between the genotype and the phenotype in five patients karyotype 46, XX with the presence of the SRY gene. Methodology: The study involves five patients referred to the laboratory under suspicion of sexual development anomalies. The diagnosis took place through hormonal and echography examinations, a classic cytogenetic study (Barr chromatin and karyotype) and an amplification of the SRY gene located on the Y chromosome. The resulting PCR products were sent for sequencing. Results: Based on the results of clinical and paraclinical tests carried out it was found clitoral hypertrophy, the presence of clitoris penis for some, presence of normal penis for others. In addition, echography revealed a lack of female internal genitalia (P2, P3), and a presence of testicles (P3, P4, P5). Genetic analysis (chromosomal and molecular) showed a karyotype 46, XX SRY (+) for all patients. New mutations were found c.246 T > A, p.82 Asn82Lys and c.171 G > C, p.57 Gln57His. Conclusion: In our study, we were able to correlate each DSD with karyotype 46, XX to a pathology such as 46, XX DSD testicular, 46, XX DSD with clitoral hypertrophy and ovotestis 46, XX. The next step will undoubtedly be the integration of other molecular techniques (genotyping, FISH, CGH or even the CGH array) to further genetic exploration.

淫羊藿苷对抑郁症模型小胶质细胞表型转化的调控作用

探索淫羊藿苷抗抑郁的作用机制,将SPF级KM小鼠分为空白组、模型组、盐酸氟西汀组(10 mg/kg)、淫羊藿苷高(50 mg/kg)、低(25 mg/kg)剂量组。除空白组外,其余各组小鼠采用56 d慢性不可预知温和应激建立抑郁症模型。造模第1 d开始灌胃给予各组小鼠相应药物,连续56 d。于给药后第53~56 d,进行行为学测试。末次给药后,取材。酶联免疫吸附剂实验(enzyme linked immunosorbent assay,ELISA)检测脑组织匀浆白细胞介素6(interleukin-6,IL-6)、白细胞介素10(interleukin-10,IL-10)、五羟色胺(5-hydroxytryptamine,5-HT)、多巴胺(dopamine,DA)、去甲肾上腺素(norepinephrine,NE)水平;实时荧光定量PCR(quantitative real-time PCR,RT-PCR)检测脑组织中IL-6、IL-10、诱导性一氧化氮合酶(inducible nitric oxide synthase,iNOS)、分化簇206(cluster of differentiation 206,CD206)mRNA表达;蛋白免疫印迹(Western blot)检测脑组织iNOS、CD206蛋白表达。体外培养小鼠小胶质细胞(BV-2),采用细胞增殖与毒性检测试剂盒(Cell Counting Kit-8,CCK-8)法检测淫羊藿苷的细胞毒性。BV-2细胞暴露于100μg/mL脂多糖及15μg/mL、25μg/mL的淫羊藿苷24 h后,收集细胞。免疫荧光技术检测细胞iNOS、CD206蛋白表达。研究结果表明,慢性不可预知温和应激致抑郁症模型制备成功,淫羊藿苷可降低抑郁症小鼠脑组织IL-6水平及IL-6、iNOS mRNA表达,升高脑组织IL-10、5-HT、DA、NE水平及IL-10、CD206 mRNA表达;降低脑组织iNOS蛋白,升高CD206蛋白表达;改善模型小鼠抑郁症样行为。淫羊藿苷可降低LPS刺激的BV-2细胞iNOS蛋白表达,升高CD206蛋白表达。结果表明,淫羊藿苷抑制小胶质细胞M1表型转化,促进M2表型转化,从而改善模型小鼠抑郁样行为。

非酒精性脂肪肝动物模型和疾病表型的研究进展

非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)是一种以肝细胞脂肪堆积为特征的疾病,随着患病率的不断增高,NAFLD已成为全人类的健康问题。在NAFLD数十年的研究历史中,动物模型在发病机制、病理生理、治疗和预防的研究设计中发挥了不可替代的作用。NAFLD的动物模型种类繁多,按照动物的品种品系、造模时间和方法、造模判定指标进行总结,根据不同动物和方法得到的模型进行评估,比较模型与人类NAFLD的相似度和优缺点。

基于深度主动学习与CBAM的细粒度菊花表型识别

针对菊花种类繁多,花型差别细微,准确标注比较困难的问题,基于深度主动学习与混合注意力机制模块(Convolutional block attention module,CBAM),提出了一种标号数据不足情况下的菊花表型智能识别方法和框架。首先,通过主动学习策略基于最优标号和次优标号法(Best vs second-best,BvSB)在未标记菊花样本中选取信息量较大的样本进行标记,并将标记后的样本放入训练样本中;其次,使用深度卷积神经网络ResNet50作为本文的主干网络训练标记样本,引入混合注意力机制模块CBAM,使模型能够更为准确地提取细粒度图像中的高层语义信息;最后,用更新后的训练样本继续训练分类模型,直到模型达到迭代次数后停止。实验结果表明,该方法在少量菊花标记样本下,精确率、召回率和F1值分别达到93.66%、93.15%和93.41%。本文方法可为标号数据不足情况下的菊花等花卉智能化识别提供技术支撑。

基于CNN的作物分类识别图像获取平台研究进展

基于机器视觉的作物精准分类识别是农业自动化、智能化作业的前提。在作物图像分类识别任务中,卷积神经网络(CNN)是当前应用最广泛的算法之一。作物表型特征及生长环境的复杂性,决定作物图像获取平台的多样性。通过分析2020—2022年国内外基于CNN的作物分类识别研究,图像获取平台可划分为通用平台和自建平台两大类:通用平台硬件产品成熟、部署方便,但要做好设备选型和环境搭建;自建平台分为固定式和移动式,能高效获取试验数据,但硬件集成较为复杂。详细对比分析各类平台的优缺点及适用范围。作物图像获取平台的未来趋势包括:高通量、高效率、自动化的通用图像获取装置,集成多种传感器的多模态数据采集与融合应用,自带运算处理的智能摄像头等,更精细化的图像获取平台将有效支撑作物表型的深入研究。

基于1DCNN融合多源表型数据的杨树干旱胁迫评估方法

目前关于不同杨树品种抗旱性的研究主要集中在利用传统测量方法获取形态结构和生理生化表型参数进而分析杨树的抗旱性,依据多源成像传感器提取的表型参数指标确定杨树干旱胁迫等级的方法较为少见。为了阐明杨树耐旱的表型机制、筛选抗旱性树种和明确杨树抗旱等级,本文以杨树不同性别的喜水和耐旱品种为研究对象,在杨树苗期进行梯度干旱胁迫处理,通过热红外以及RGB多源成像传感器获取杨树冠层温度参数与颜色植被指数表型数据,并建立基于1DCNN的多任务分类模型划分杨树苗期品种抗旱等级与干旱胁迫等级等2个分类任务,探究杨树性别与生长时间对杨树干旱胁迫响应机制的影响。结果表明,以27组数据变量降维后的4个特征作为模型变量,与传统机器学习算法SVM、RF、XGBoost相比,本文提出的1DCNN多任务分类模型在杨树品种抗旱等级分类与单株干旱胁迫等级分类2个任务中的模型分类精度皆达到最优,分类准确率分别为81.8%和62.3%;引入杨树的性别和生长时间后共6个特征作为模型的输入变量后,杨树苗期品种抗旱等级与干旱胁迫等级的分类精度显著提高,1DCNN多任务分类模型在2个分类任务中的准确率分别达到93.5%与76.6%,模型分类准确率分别提高11.7个百分点与14.3个百分点。研究结果表明,通过热红外与RGB成像传感器获取多源表型数据,并建立1DCNN多任务分类模型对实现杨树干旱胁迫等级评估的可行性,同时表明杨树的性别和生长时间作为模型输入变量能够有效提升模型的分类精度,可为筛选杨树抗旱性品种提供新的思路与方法。

玉米矮秆突变体20F421的表型鉴定及遗传分析

矮秆资源是农作物矮化育种的物质基础,发掘矮秆基因资源对培育矮秆新品种具有重要作用。为了明确^(252)CF裂变快中子辐射诱变玉米自交系KWS49筛选得到的矮秆突变体20F421的遗传特性和矮化机理,以20F421为材料分别与玉米自交系PH6WC、B73、Mo17及KWS49杂交构建F_(1)和F_(2)分离群体,分析矮秆性状的遗传模式,并以(20F421/B73)F_(2)为定位群体,采用混池转录组测序(bulked segregant RNA-seq,BSR-seq)方法初步定位突变基因。结果表明,与KWS49相比,20F421的植株高度为95.2 cm,降低47.89%;穗位高度为23.9 cm,降低64.54%;茎秆节间长度显著缩短、叶片较直立密生,自交结实良好。遗传分析表明,F2分离群体野生型(高秆)与突变型(矮秆)植株性状分离比例符合3∶1,表明该突变体受单个核隐性基因控制;BSR-seq结果将突变基因定位在1号染色体177~255 Mb之间。通过与B73参考基因组进行比对发现,该区间内含有矮秆基因Br2,将20F421与br2突变体杂交进行等位性检测,F_(1)和F_(2)的株高均没有发生性状分离,表现为突变体20F421和br2表型,推测20F421的矮秆突变基因为矮秆基因Br2的等位突变。研究结果为进一步精细定位、克隆突变基因奠定基础,也为解析玉米矮化机理和培育矮秆玉米新品种提供重要基因资源和理论支撑。