Interleukin-1 receptor associated kinase 2 is a functional downstream regulator of complement factor D that controls mitochondrial fitness in diabetic cardiomyopathy

Diabetic cardiomyopathy is a disorder of the cardiac muscle that affects patients with diabetes.The exact mechanisms underlying diabetic cardiomyopathy are mostly unknown,but several factors have been implicated in the pathogenesis of the disease and its progression towards heart failure,including endothelial dysfunction,autonomic neuropathy,metabolic alterations,oxidative stress,and alterations in ion homeostasis,especially calcium transients[1].In Military Medical Research,Jiang et al.[2]sought to determine the functional role of complement factor D(Adipsin)in the pathophysiology of diabetic cardiomyopathy.

Analyze interleukin-1β,interleukin-6,and tumor necrosis factor-αlevels in dry eye and the therapeutic effect of cyclosporine A

BACKGROUND Dry eye is a common eye disease.Artificial tears supplements are widely used for the treatment of dry eyes.However,multiple adverse effects have been observed in patients receiving long-term treatment with artificial tears,which may affect the therapeutic effect.AIM To analyze the characteristics of interleukin-1β(IL-1β),interleukin-6(IL-6),and tumor necrosis factor-alpha(TNF-α)levels in patients with dry eye and the therapeutic effect of artificial tears combined with cyclosporine A.METHODS A total of 124 dry eye patients treated at The First People’s Hospital of Xining from April 2020 to April 2022 were selected as the observation group,while 20 healthy individuals served as the control group during the same period.Levels of inflammatory markers,including IL-1β,IL-6,and TNF-α,were analyzed.The observation group was further divided into a study group and a control group,each consisting of 62 patients.The control group received artificial tears,whereas the study group received a combination of artificial tears and cyclosporine A.Inflammatory markers,Schirmer’s test(SIT),tear break-up time(TBUT),corneal fluorescein staining(CFS),National Eye Institute Visual Function Questionnaire-25(NEI-VFQ-25)scores,and adverse events(AEs)were compared between the two groups.RESULTS The observation group exhibited significantly elevated serum levels of IL-1β,IL-6,and TNF-αin comparison to the healthy group.Following treatment,the study group demonstrated substantial reductions in IL-1β,IL-6,and TNF-αlevels relative to the control group.Moreover,after treatment,the study group experienced a marked decrease in CFS scores and significant increases in both SIT and BUT levels when compared to the control group.Additionally,significant improvements were observed in the primary symptom of dry eye and secondary symptoms such as photophobia,foreign body sensation,fatigue,red eye,and burning sensation within the study group.Furthermore,post-treatment NEI-VFQ-25 scores across all dimensions exhibited significant enhancements in the study group compared to the control group(P<0.05).It is noteworthy that significant AEs were reported in both groups throughout the treatment period.CONCLUSION Cyclosporine A combined with artificial tears is effective in treating dry eye,yielding enhanced outcomes by improving SIT and TBUT levels,reducing CFS scores,and ameliorating vision-related quality of life.

Interleukin-1β:Friend or foe for gastrointestinal cancers

Gastrointestinal(GI)cancer is a malignancy arising in the digestive system and accounts for approximately a third of increasing global cancer-related mortality,especially in the colorectum,esophagus,stomach,and liver.Interleukin-1β(IL-1β)is a leukocytic pyrogen recognized as a tumor progression-related cytokine.IL-1βsecretion and maturation in inflammatory responses could be regulated by nuclear factor-kappaB-dependent expression of NLR family pyrin domain containing 3,inflammasome formation,and activation of IL-1 converting enzyme.Several studies have documented the pro-tumorigenic effects of IL-1β in tumor microenvironments,promoting proliferation and metastatic potential of cancer cells in vitro and tumorigenesis in vivo.The application of IL-1β inhibitors is also promising for targeted therapy development in some cancer types.However,as a leukocytic pro-inflammatory cytokine,IL-1β may also possess anti-tumorigenic effects and be type-specific in different cancers.This editorial discusses the up-to-date roles of IL-1β in GI cancers,including underlying mechanisms and down-stream signaling pathways.Understanding and clarifying the roles of IL-1β would significantly benefit future therapeutic targeting and help improve therapeutic outcomes in patients suffering from GI cancer.

梨杂交F_(1)果实性状遗传倾向分析

以延边大香水为母本,红香酥、早酥、红茄、晋酥、晋密、鄂梨1号和云红1号为父本的7个梨杂交组合F_(1)为试材,对果实性状进行连续3年调查,总结分析果实性状遗传倾向,以期为梨遗传育种提供参考依据。结果表明:杂种F_(1)单果重、果实横径、果实纵径、果柄长度、果柄粗度、果形指数及可溶性固形物等7个性状都有趋中遗传倾向。其中,单果重产生退化,向小果遗传趋势强;可溶性固形物和果形指数变异系数较小,遗传传递力较高;果柄粗度呈趋中偏低遗传,果柄长度、果实横径、果实纵径呈趋中偏高遗传。对不同组合果实性状遗传倾向研究认为果实底色、萼片类型、萼洼深度、质地、汁液、风味等性状受母本影响较大,为母性遗传;萼洼广度有趋中遗传倾向;果实香气受父本影响较大;果实面色可隔代遗传。以上研究结果为梨果实性状遗传规律研究及杂交育种亲本的选择选配提供参考价值。

X线修复交叉互补基因1多态性与进展期胃癌奥沙利铂联合卡培他滨方案化疗疗效的关系

目的:探讨X线修复交叉互补基因1(X-ray repair cross-complementing group 1,XRCC1) rs25487基因多态性与进展期胃癌奥沙利铂联合卡培他滨(XELOX方案)化疗的疗效及疾病进展时间的关系。方法:本研究为回顾性研究,入组110例进展期胃癌患者,均接受XELOX方案化疗,通过基质辅助激光解吸电离飞行时间质谱法的方法检测XRCC1 rs25487基因分型,分析患者临床病理特点及XRCC1 rs25487基因分型与患者化疗客观有效率(objective response rate, ORR)及疾病进展时间(progression-free survival, PFS)的关系。结果:110例进展期胃癌患者中,携带XRCC1 rs25487GG基因型、AG基因型、AA基因型分别为49例(44.5%)、52例(47.3%)、9例(8.2%),GG基因型患者ORR高于AG/AA基因型患者(53.1%vs 37.7%),但差异未达到统计学意义(χ^(2)=2.594,P=0.107)。GG基因型患者比AG/AA基因型患者PFS更长[6.3个月(95%CI:5.7~6.9)vs 5.0个月(95%CI:4.4~5.6),P=0.049]。患者临床病理特征均与化疗疗效无关,但肿瘤分化程度及TNM分期与PFS有关(P均<0.05)。Cox回归显示,肿瘤分化程度、TNM分期及XRCC1 rs25487是影响PFS的独立因素。结论:XRCC1 rs25487基因型与进展期胃癌患者XELOX方案化疗疗效密切相关,测定XRCC1 rs25487基因型可以为进展期胃癌的个体化治疗提供参考。

LZTR1基因Arg284His变异致Noonan综合征10型病例报道和遗传学分析

目的 对1例Noonan综合征10型(NS10)患儿进行临床特征和遗传学分析。方法 对患儿及其父母进行家系全外显子组(trio-WES)检测,采用生物信息学方法对基因变异进行危害性分析,预测变异蛋白结构功能,采用免疫印迹法检测变异蛋白的表达量。结果 患儿年龄为8岁9个月,临床表现为生长发育迟缓、先天性心脏病和特殊面容等。基因检测结果提示患儿亮氨酸拉链样转录调控因子1(LZTR1)基因发生杂合变异c.851G>A(p.Arg284His)(NM_6767.4),其父亲携带该变异,母亲为野生型。Pubmed数据库和HGMD数据库未检索到相应变异的报道,属LZTR1基因新变异。SIFT、Polyphen-2和MutationTaster在线软件分析结果显示到LZTR1 c.851G>A(p.Arg 284His)变异存在生物危害性。蛋白结构模型分析结果显示,LZTR1 c.851G>A(p.Arg 284His)变异可导致LZTR1蛋白局部结构改变。免疫印迹法结果显示,与野生型LZTR1蛋白比较,变异型LZTR1蛋白的表达量降低了81.20%。结论 LZTR1基因c.851G>A(p.Arg 284His)变异可能是NS10的致病原因。

基于BP神经网络模型优化Fe_(1-x)O基氨合成催化剂

运用BP神经网络建立了助催化剂含量与催化剂活性之间的预测模型,对Fe_(1-x)O基氨合成催化剂的助催化剂进行优化。首先将前期实验数据整理归纳为含有3、4、5、6和7个助催化剂等5类催化剂,以助催化剂含量(体积分数)为输入变量,以425℃反应器出口氨浓度(活性)为输出变量,对助催化剂进行优化。结果表明,BP神经网络预测模型拟合值均方误差最高为0.2784,预测值均方误差最高为0.1592,构建的BP神经网络模型准确度较高。在该模型的基础上,运用多种群遗传算法进行极值寻优,求解最优的催化剂配方,并进行实验验证。结果表明,根据优化结果制备5个样品的实验测定值与预测值的相对误差最高为2.88%,优化结果较为准确;含有7个助催化剂的催化剂活性最高为18.83%,比原样本的统计平均活性值(17.52%)高1.31%,相对提高7.48%,助催化剂含量优化取得满意的结果。

Interleukin-1:an important target for perinatal neuroprotection?

Perinatal inflammation is a significant risk factor for lifelong neurodevelopmental impairments such as cerebral palsy.Extensive clinical and preclinical evidence links the severity and pattern of perinatal inflammation to impaired maturation of white and grey matters and reduced brain growth.Multiple pathways are involved in the pathogenesis of perinatal inflammation.However,studies of human and experimental perinatal encephalopathy have demonstrated a strong causative link between perinatal encephalopathy and excessive production of the pro-inflammatory effector cytokine interleukin-1.In this review,we summarize clinical and preclinical evidence that underpins interleukin-1 as a critical factor in initiating and perpatuating systemic and central nervous system inflammation and subsequent perinatal brain injury.We also highlight the important role of endogenous interleukin-1 receptor antagonist in mitigating interleukin-1-driven neuroinflammation and tissue damage,and summarize outcomes from clinical and mechanistic animal studies that establish the commercially available interleukin-1 receptor antagonist,anakinra,as a safe and effective therapeutic intervention.We reflect on the evidence supporting clinical translation of interleukin-1 receptor antagonist for infants at the greatest risk of perinatal inflammation and impaired neurodevelopment,and suggest a path to advance interleukin-1 receptor antagonist along the translational path for perinatal neuroprotection.

Interleukin-12 and Th1 immune response in Crohn’s disease: Pathogenetic relevance and therapeutic inplication

Crohn’s disease (CD) and ulcerative colitis (UC) are chronic inflammatory disorders of the gastrointestinal tract that share clinical and pathological characteristics. The most accredited hypothesis is that both CD and UC result from a deregulated mucosal immune response to normal constituents of the gut microflora. Evidence, however, indicates that the main pathological processes in these two diseases are distinct. In CD, the tissue- damaging inflammatory reaction is driven by activated type 1 helper T-cell (Th1), whereas a humoral response predominates in UC. Consistently, a marked accumulation of macrophages making interleukin (IL)-12, the major Th1-inducing factor, is seen in CD but not in UC mucosa. Preliminary studies also indicate that administration of a monoclonal antibody blocking the IL-12/p40 subunit can be useful to induce and maintain clinical remission in CD patients. Notably, the recently described IL-23 shares the p40 subunit with IL-12, raising the possibility that the clinical benefit of the anti-IL-12/p40 antibody in CD may also be due to the neutralization of IL-23 activity. This review summarizes the current information on the expression and functional role of IL-12 and IL- 12-associated signaling pathways both in patients with CD and experimental models of colitis, thus emphasizing major differences between IL-12 and IL-23 activity on the development of intestinal inflammation.

Homer1a reduces inflammatory response after retinal ischemia/reperfusion injury

Elevated intraocular pressure(IOP)is one of the causes of retinal ischemia/reperfusion injury,which results in NRP3 inflammasome activation and leads to visual damage.Homerla is repo rted to play a protective role in neuroinflammation in the cerebrum.However,the effects of Homerla on NLRP3inflammasomes in retinal ischemia/reperfusion injury caused by elevated IOP remain unknown.In our study,animal models we re constructed using C57BL/6J and Homer1^(flox/-)/Homerla^(+/-)/Nestin-Cre^(+/-)mice with elevated IOP-induced retinal ischemia/repe rfusion injury.For in vitro expe riments,the oxygen-glucose deprivation/repe rfusion injury model was constructed with M uller cells.We found that Homerla ove rexpression amelio rated the decreases in retinal thickness and Muller cell viability after ischemia/reperfusion injury.Furthermore,Homerla knockdown promoted NF-κB P65^(Ser536)activation via caspase-8,NF-κB P65 nuclear translocation,NLRP3 inflammasome formation,and the production and processing of interleukin-1βand inte rleukin-18.The opposite results we re observed with Homerla ove rexpression.Finally,the combined administration of Homerla protein and JSH-23 significantly inhibited the reduction in retinal thickness in Homer1^(flox/-)Homer1a^(+/-)/Nestin-Cre^(+/-)mice and apoptosis in M uller cells after ischemia/reperfusion injury.Taken together,these studies demonstrate that Homer1a exerts protective effects on retinal tissue and M uller cells via the caspase-8/NF-KB P65/NLRP3 pathway after I/R injury.

猫疱疹病毒1型的检测及一株分离毒株的致病性

旨在调查成都地区的猫疱疹病毒1型(feline herpesvirus-1, FHV-1)的流行及遗传变异情况。试验选取2020—2023年从成都地区采集的178份具有呼吸道症状猫的眼、鼻及口咽拭子进行FHV-1核酸检测、gE基因遗传进化分析、FHV-1的分离鉴定和致病性研究。结果发现,成都地区FHV-1阳性率为11.8%(21/178);其中宠物医院FHV-1阳性率为6.4%(7/110),猫舍FHV-1阳性率为20.6%(14/68),表明在猫舍中FHV-1感染率更高。FHV-1 gE基因的遗传进化分析结果表明,本研究扩增出的5株gE基因和疫苗株的核苷酸同源性在99.1%~100%,并发现PX-9株存在3个独特的氨基酸突变位点(L259Q、C294I、W295F)。通过CRFK细胞对5份阳性样本进行病毒的分离培养,结果PX-9毒株被成功分离鉴定。对PX-9毒株进行动物回归试验,结果表明攻毒组猫只表现出眼鼻分泌物增多,打喷嚏等临床症状,在接毒后第4天病毒拷贝数最高,为9.05×10^(7) copies·μL^(-1),且排毒期较长;攻毒猫只FHV-1病毒载量检测结果显示,气管及肺组织病毒拷贝数分别为1.7×10^(7)和3.5×10^(4) copies·μg^(-1),其它组织核酸阴性。综上表明,在成都地区仍然存在FHV-1流行,并且流行毒株有较强的致病性。

Small extracellular vesicles from hypoxia-preconditioned bone marrow mesenchymal stem cells attenuate spinal cord injury via miR-146a-5p-mediated regulation of macrophage polarization

Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.

利用“黄海芯1号”55K SNP芯片评估凡纳滨对虾选育群体的遗传多样性与基因组近交水平

凡纳滨对虾的主要选育目标分为两个方面:一是培育具有较强抗病、抗逆性的“高抗系”(GK),二是培育具有快速生长特性的“快大系”(KD)。然而,国内缺少针对这两个选育群体的遗传多样性特别是基因组近交水平的调查分析研究。基于液相芯片“黄海芯1号”(55 K SNP)的基因分型数据,首次分析了GK(1064尾个体)和KD(564尾个体)选育群体的遗传结构和遗传多样性,调查了连续性纯合片段(ROH)的基因组分布特征,并重点评估了两个群体的基因组近交水平。PCA及进化树分析表明GK及KD群体可明确分层,亲缘关系热图表明KD群体内个体间的亲缘关系比GK群体更近。GK群体包括的家系数量更多,导致其遗传多样性高于KD群体;两群体间的F_(st)为0.09,存在中等遗传分化。GK和KD群体每个ROH的平均长度分别为(1.70±0.34)Mb和(1.65±0.38)Mb,每个样本ROH的平均数量分别为1.98±1.30和2.07±1.37。GK和KD群体0.8~1.25 Mb长度的ROH占比分别为11.41%和19.17%,表明KD群体的选育历史比GK群体更长。两个群体>2.25 Mb长度的ROH片段占比分别为10.26和9.74%,表明两个群体短期内未发生近亲交配。七种基因组近交系数评估结果表明,KD群体的近交水平高于GK群体。不依赖基础群体等位基因频率的F_(ROH)和F_(HOM)方法可准确地评价育种群体的真实近交水平,而F_(VR1)、F_(YA1)和F_(LH1)等依赖基础群体等位基因频率的方法可以用来比较群体及个体间的相对近交水平。上述结果为准确地评估育种群体的近交水平和优化育种方案提供了重要参考依据。

Genetic association and epistatic interaction of the interleukin-10 signaling pathway in pediatric inflammatory bowel disease

To study the genetic association and epistatic interaction of the interleukin (IL)-10 and IL-10/STAT3 pathways in pediatric inflammatory bowel disease (IBD). METHODSA total of 159 pediatric inflammatory IBD patients (Crohn’s disease, n = 136; ulcerative colitis, n = 23) and 129 matched controls were studied for genetic association of selected single nucleotide polymorphisms (SNPs) of the IL-10 gene and the genes IL10RA, IL10RB, STAT3, and HO1, from the IL-10/STAT3 signaling pathway. As interactions between SNPs from different loci may significantly affect the associated risk for disease, additive (a) and dominant (d) modeling of SNP interactions was also performed to examine high-order epistasis between combinations of the individual SNPs. RESULTSThe results showed that IL-10 rs304496 was associated with pediatric IBD (P = 0.022), but no association was found for two other IL-10 SNPs, rs1800872 and rs2034498, or for SNPs in genes IL10RA, IL10RB, STAT3, and HO1. However, analysis of epistatic interaction among these genes showed significant interactions: (1) between two IL-10 SNPs rs1800872 and rs3024496 (additive-additive P = 0.00015, Bonferroni P value (Bp) = 0.003); (2) between IL-10RB rs2834167 and HO1 rs2071746 (dominant-additive, P = 0.0018, Bp = 0.039); and (3) among IL-10 rs1800872, IL10RB rs2834167, and HO1 rs2071746 (additive-dominant-additive, P = 0.00015, Bp = 0.005), as well as weak interactions among IL-10 rs1800872, IL-10 rs3024496, and IL-10RA (additive-additive-additive, P = 0.003; Bp = 0.099), and among IL10RA, IL10RB, and HO1 genes (additive-dominant-additive, P = 0.008, Bp = 0.287). CONCLUSIONThese results indicate that both the IL-10 gene itself, and through epistatic interaction with genes within the IL-10/STAT3 signaling pathway, contribute to the risk of pediatric IBD.

农杆菌介导的“野大1号”高效遗传转化体系建立

栽培大豆在驯化过程中丢失了大量的优异基因,我国野生大豆种质资源丰富,蕴含着许多高蛋白、抗逆方面的基因。大豆新品种“野大1号”作为一份重要的种质资源,保存着宝贵的遗传基因和许多优良的性状,具有较高的营养价值,其中异黄酮的含量高达千分之二,在农业育种上具有重要的价值。本研究以“野大1号”为材料,通过设计不同的消毒方式和时间以及不同的芽诱导6-BA浓度配比,通过GUS染色方法比较摇床和针管真空渗漏两种侵染方式在不同侵染时间下对基因转化效率的影响,分析侵染后外植体最佳抗生素筛选浓度,建立“野大1号”大豆品种的高效遗传转化体系。结果表明:“野大1号”种子消毒最佳方法为75%酒精消毒45 s后再使用15%过氧化氢消毒30 min;最佳侵染方法为针管真空渗漏浸染30 min;最佳不定芽诱导培养基为MS+2 mg·L^(-1)6-BA;抗性筛选标记潮霉素的最适浓度为60 mg·L^(-1)。通过该遗传转化体系成功移栽了14株植株,其中8株为转基因阳性植株。该高效再生及遗传转化体系的建立为大豆的新品种培育奠定坚实基础。

Current understandings of the pathogenesis of type 1 diabetes:Genetics to environment

Type 1 diabetes(T1D)is an autoimmune disease that usually strikes early in life,but can affect individuals at almost any age.It is caused by autoreactive T cells that destroy insulin-producing beta cells in the pancreas.Epidemiological studies estimate a prevalence of 1 in 300 children in the United States with an increasing incidence of 2%-5%annually worldwide.The daily responsibility,clinical management,and vigilance required to maintain blood sugar levels within normal range and avoid acute complications(hypoglycemic episodes and diabetic ketoacidosis)and long term micro-and macro-vascular complications significantly affects quality of life and public health care costs.Given the expansive impact of T1D,research work has accelerated and T1D has been intensively investigated with the focus to better understand,manage and cure this condition.Many advances have been made in the past decades in this regard,but key questions remain as to why certain people develop T1D,but not others,with the glaring example of discordant disease incidence among monozygotic twins.In this review,we discuss the field’s current understanding of its pathophysiology and the role of genetics and environment on the development of T1D.We examine the potential implications of these findings with an emphasis on T1D inheritance patterns,twin studies,and disease prevention.Through a better understanding of this process,interventions can be developed to prevent or halt it at early stages.

The role of Interleukin-1 family in cardiovascular disease and its research progress

The interleukin-1 family is a group of important cytokines that play a key regulatory role in the immune and inflammatory response(including infectious and non-bacterial injuries).Nowadays,the interleukin-1 family mainly includes 11 cytokines and has multiple roles in the pathology and physiology of inflammation.Moreover,accumulating number of research show that the interleukin-1 family and its receptors are involved in the occurrence and development of cardiovascular diseases.Therefore,we show here the review involving hotspots of the interleukin-1 family in the process of inflammation and its target therapy in cardiovascular diseases,including atherosclerosis,myocardial infarction and heart failure.

WFS1基因相关遗传性耳聋的研究进展

WFS1基因位于染色体4p16.1,编码一种内质网跨膜Wolfram蛋白,参与调节内质网钙离子的动态平衡,在蛋白质转运和细胞凋亡中发挥重要作用。WFS1基因突变与多种遗传性疾病相关联,存在听力损失症状的类型主要为隐性遗传Wolfram综合征1型、显性遗传的Wolfram相似综合征以及非综合征型低频感音神经性聋(LFSNHL)DFNA6/14/38。Wolfram综合征1型临床表型具有很高的异质性,包括尿崩症、糖尿病、视神经萎缩以及耳聋。Wolfram相似综合征报道很少,与Wolfram综合征1型主要的区别点在于其显性遗传模式。WFS1基因是引起非综合征LFSNHL最常见的致病基因。我们综述WFS1基因关联的遗传性耳聋相关疾病,为临床诊疗提供指导。

基于线粒体COX1和ND1基因顺序的黄河上游大鼻吻鮈遗传多样性分析

为探究黄河上游大鼻吻鮈(Rhinogobio nasutus)群体遗传多样性和遗传分化现状,本研究以永宁、平罗、磴口3个不同地理群体145尾大鼻吻鮈为研究对象,利用线粒体DNA COX1和ND1基因序列进行了遗传多样性分析。结果显示:COX1和ND1基因序列长度分别为1 466 bp、975 bp, A+T含量(57.25%,56.81%)均高于G+C(42.75%,43.19%)含量,具有明显的碱基组成偏向性;3个群体145尾样本中分别界定了11个和9个单倍型,均存在共享单倍型现象。在COX1和ND1基因序列中3个群体的平均单倍型多样性(Hd)、核苷酸多样性(π)及平均核苷酸差异(K)分别为0.745 3、0.001 3、1.841和0.364、0.000 48、0.472,3个群体遗传多样性呈现出磴口群体最高、平罗群体次之、永宁群体最小的特征。基于COX1和ND1的遗传变异分析(AMOVA),表明3个群体中遗传变异均主要来自群体内,且COX1基因序列中磴口群体与永宁群体之间存在显著性明显的遗传分化。基于线粒体COX1和ND1基因单倍型序列,采用邻近法(Neighbor Joining, NJ)构建系统进化树与单倍型网络结过具有一致性,表明3个群体之间无明显的谱系分化,结构比较单一,未发现形成单独分支的群体。中性检验结果显示,大鼻吻鮈进化历程符合中性进化假设,且可能存在群体扩张。因此,为了有效地保护大鼻吻鮈野生资源,建议将大鼻吻鮈从整体上进行就地保护。

‘窄冠白杨1号’遗传转化体系建立与抗虫基因转化

‘窄冠白杨1号’(Populus leucopyramidalis 1)是一种冠形窄、耐盐碱的优良白杨派无性系。由于缺乏其遗传转化体系,因此无法通过基因工程手段对其进行遗传改良。该研究以‘窄冠白杨1号’为材料,建立了农杆菌介导的遗传转化体系,并获得了较高的遗传转化效率。首先将组培苗继代培养不同时间段(35、45、55、65 d),分别取其3种组织(叶片、叶柄、茎段)以对比分化能力的强弱,确定了继代45 d后的叶片具有最强的分化能力,其增殖倍数为8.77。随后,使用继代45 d后的叶片作为遗传转化的材料,研究不同侵染条件对转化率的影响,设立了菌液浓度、侵染时间和共培养时间各3个梯度的正交试验,对这3个因素进行最佳水平筛选,通过PCR检测和GUS染色鉴定转基因株系。结果表明‘窄冠白杨1号’遗传转化体系的最佳组合为:菌液浓度OD600=0.4,侵染时间15 min,共培养时间2 d,在该组合下转化率最高可达54.23%。最后,利用该遗传转化体系获得了转BtCry3Aa抗虫基因‘窄冠白杨1号’株系,证明该体系可以做为‘窄冠白杨1号’遗传改良的有效方法。