A high-quality genome of Actinidia eriantha provides new insight into ascorbic acid regulation

Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics,metabolomics and transcriptomics.We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps.The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb.Among them,24 of the pseudochromosomes were obtained directly from telomere-to-telomere.The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively.Subsequently, 61 metabolites and 2 092genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively.AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development,suggesting its crucial role in the regulation of AsA.Furthermore,the AsA contents are highly associated with ascorbate peroxidase genes.The genome obtained in this study provides genomic resources for the genetic and breeding research ofA. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit.

Actinidia deliciosa as a complemental therapy against nephropathy and oxidative stress in diabetic rats

This study aimed to evaluate the anti-hyperglycemic and antioxidant role of Actinidia deliciosa(kiwifruits)aqueous extract in streptozotocin-treated rats.Animals were distributed into;control,A.deliciosa aqueous extract(ADAE;1 g/kg orally),streptozotocin(STZ;50 mg/kg,i.p,single dose),and STZ plus ADAE,respectively.Results showed that ADAE had high antioxidant and radical scavenging potency.Elevation in blood sugar level,lipid peroxidation(LPO),kidney function biomarkers,and perturbations in hematological parameters were observed in diabetic rats.While,enzymatic and non-enzymatic antioxidants,protein content,and alkaline phosphatase(ALP)activity declined.Furthermore,histological,immunohistochemical alpha-smooth muscle actin immunoreactivity(α-SMA-ir)and histochemical(collagen,total protein,DNA,and RNA)alterations were observed in rat kidneys.Moreover,STZ produced upregulation of inflammatory associated genes(tumor necrosis factor-alpha;TNF-αand transforming growth factorβ1;TGF-β1)and triggered apoptosis by upregulating apoptotic related gene[Bcl2-associated X protein(Bax)]and downregulating anti-apoptotic related gene B-cell lymphoma-2(Bcl-2)based on real-time PCR data.Moreover,diabetic rats administered with ADAE showed significant restoration in LPO,antioxidant status,and biochemical indices besides tissue architecture,and genes improvement regarding STZ group.Conclusively,A.deliciosa has a valuable ameliorative infl uence and can restore glucose levels and improve kidney dysfunction in diabetic rats.

Polyphenols and pectin enriched golden kiwifruit (Actinidia chinensis) alleviates high fructose-induced glucolipid disorders and hepatic oxidative damage in rats:in association with improvement of fatty acids metabolism

This study aimed to investigate the protective effects of fleshes from two Actinidia chinensis(ACF), pericarps from two A. chinensis(ACP), and fleshes with pericarps from two A. chinensis(ACFP)on high fructose(HF)-instigated dyslipidemia, hepatic steatosis, oxidative stress, insulin resistance, and fatty acid metabolism disorders in rats. In general, the above abnormalities were improved after 10 weeks intervention of ACF, ACP, and ACFP. Especially, ACFP considerably ameliorated HF-induced abnormal changes in body weight gain, serum TC, TG, LDL-C and HDL-C levels, as well as serum and hepatic SFAs, MUFAs and PUFAs contents. ACFP also alleviated HF-induced hyperglycemia and hyperinsulinemia, stabilized HF-caused increase in hepatic MDA and serum ALT, AST levels, and restored HF-declined hepatic T-SOD and GSH-Px activities. Besides, histopathology of the liver further endorsed the protective effects of ACFP on hepatocellular injury. Moreover, ACFP increased HF-dropped acetic, propionic and butyric acid levels. Overall, ACFP employs more efficacious protective effects against HF-induced metabolic disorders and liver damage than ACF and ACP. This study delivers a scientific foundation for developing kiwifruit(counting peel)-based dietary supplements for those with glucolipid-metabolic disorders and liver damage.

Actinidia chinensis Planch.root extract downregulates the Wnt/β-catenin pathway to treat gastric cancer:a mechanism study based on network pharmacology

Background:Actinidia chinensis Planch.roots(AcRoots)have been applied as an anti-inflammatory and antitumor drug in the treatment of gastric cancer(GC).However,their mechanisms against GC cells remain unclear.To investigate the anticancer effect of AcRoots in GC and the possible underlying mechanism by using network pharmacology.Methods:Differentially expressed genes between gastric precancerous lesions and cancer were analyzed in Gene Expression Omnibus datasets,and these genes were overlapped with potential targets of AcRoots.Potential targets and pathways for AcRoots treatment of GC predicted by network pharmacology.Furthermore,we used the GC cell line HGC27 to explore the molecular mechanisms in the context of hub genes in apoptosis,invasion,metastasis,and epithelial to mesenchymal transition-promoting factors.Molecular docking between hub targets and active drug components was also performed.Results:Network pharmacological analysis suggested that the potential mechanism was related to the Wnt pathway and predicted nine hub genes.In in vitro studies,AcRoots significantly decreased HGC27 cell viability and promoted apoptosis by upregulating caspase3 and downregulating Bcl2.Moreover,it suppressed invasion and metastasis as well as the expression of epithelial to mesenchymal transition-related factors.In addition,AcRoots affected the phosphorylation level of GSK3β(Ser9)in the Wnt pathway to promote the degradation ofβ-catenin,resulting in the downregulation of the downstream target genes c-myc,cyclin D1 and snail.All the experimental results were consistent with the network pharmacology results.Conclusion:This study combined network pharmacology with in vitro experiments to provide valid evidence for the clinical promotion of AcRoots.

猕猴桃属(Actinidia)植物的遗传多样性

猕猴桃属（Actinidia）植物全世界有66个种、约118个种下分类单位（变种、变型）。中国有猕猴桃属62个种，猕猴桃遗传资源极为丰富。本文就猕猴桃的遗传资源多样性主要特点作概要综述：1）形态性状多样性（重要的园艺及经济性状）；2）营养成分及风味多样性；3）性别变异；4）染色体倍性变异；5）同工酶水平遗传多样性；6）DNA水平遗传多样性。

陕西省猕猴桃细菌性溃疡病菌(Pseudomonas syringae pv.actinidiae)Rep-PCR的遗传多样性分析

【目的】由丁香假单胞猕猴桃致病变种(Pseudomonas syringae pv.actinidiae,Psa)引起的溃疡病是猕猴桃生产中最具毁灭性的病害,明确病菌的群体遗传特性将对了解病害发生规律和防治策略的制定具有重要理论意义。【方法】采用ERIC-PCR(enterobacterial repetitive inter-genic consensus)和BOX-PCR指纹技术分析了陕西省猕猴桃主要栽培区Psa的遗传特性。【结果】ERIC-PCR聚类结果显示,相似系数为0.626时,72个Psa菌株被分为6个类群,其中供试菌株中的75.7%属于第Ⅱ类群,且菌株无明显的采集地和寄主品种的聚类。BOX-PCR指纹聚类分析可将86个Psa菌株分为8个类群(相似系数为0.668),其中第Ⅰ类群菌株数量最多,占供试菌株数量的69.8%,其地理来源为眉县、周至、杨凌及其全部的意大利供试菌株,其中来源眉县的81.6%的菌株都聚集在该类群;菌株未表现出明显的寄主品种类群。【结论】陕西省猕猴桃溃疡病菌基因组存在丰富的遗传多样性;ERIC-PCR和BOX-PCR多态性分析技术可为我国Psa基因多样性的研究提供一个有效途径。

猕猴桃属(Actinidia)植物的离体种质保存

本文研究了猕猴桃属植物离体种质资源保存的方法。在一年中于盛夏时采取的植物材料在离体培养时能得到最好的效果；改进的剥离茎尖的方法使污染率大大降低，在ＭＳ附加ＢＡ０．５，Ｚ０．１，ＧＡ０．１～０．５ｍｇ／Ｌ，蔗糖３％，琼脂０．５５％的培养基中茎尖生长良好并且不产生不定芽。通过茎尖培养方法已保存了１０多个种，４０多个猕猴桃的离体种质。

大籽猕猴桃(Actinidia macrosperma)离体再生系统的建立

大籽猕猴桃,其根茎是著名抗癌中药,中药名称猫人参,其野生资源已近枯竭.本文选用大籽猕猴桃的茎段(至少带一个节)和叶片作为外植体,筛选出了从启动、快繁直至生根等各个阶段的最适培养基,在实验室建立了程序简单、重复性好的离体快繁体系,实现了大籽猕猴桃组培苗的快速繁殖.实验发现以茎段作为外植体效果较好,既容易消毒,又能很快诱导腋芽萌发;以叶片作为外植体,能成功诱导出愈伤组织,但此愈伤组织的分化能力极低.以茎段作为外植体获得的无菌培养物在不同发育阶段适宜的培养基组成:外植体启动培养基为MS+BA5μmol/L+NAA1μmol/L;最适增殖培养基为MS+BA2μmol/L+GA1.5μmol/L+ZT4μmol/L,35d繁殖系数为9～10;最适生根培养基为1/4MS+IBA2μmol/L,生根率可达100%,培养35d,平均苗高6.28cm,平均移栽成活率为91%.

中华猕猴桃(Actinidiachinensis)在中国的适生性及其潜在地理分布模拟预测

利用181个地理分布调查数据,基于Arc GIS对中华猕猴桃的目前分布进行空间重建,利用Max Ent生态位模型对中华猕猴桃在中国的适生性及其未来气候变化下潜在可扩散地理范围进行了模拟与预测,分析中华猕猴桃在中国的适生性和扩散潜力及其空间格局,在未来气候变化背景下,预测中华猕猴桃当代及未来至2050年适生区分布格局变化。结果表明:中华猕猴桃当前的潜在适生区主要分布在23°―35°N之间和102°E以东的中亚热带山地丘陵区,如秦岭―大巴山、云贵高原、罗霄山脉―南岭和武夷山脉等地区。中华猕猴桃在当前气候条件下适生区总面积为2 382 381 km2,占中国版图的25.19%,在中等温室气体排放(RCP4.5)情景下预测至2050年,适生区总面积相对当前气候情景略有减少,但空间分布格局变化强烈。预测结果表明:在未来气候变暖影响下,中华猕猴桃潜在适生区具有向北或高纬度地区迁移的趋势。

江西猕猴桃属(Actinidia)植物的分布及其区系特征

通过野外调查和查阅大量标本、文献,对江西猕猴桃属植物的分布和区系特征进行了系统研究。江西省境内分布有猕猴桃属植物20种和11变种(或变型),其中葛枣猕猴桃(Actinidiapolygama(Sieb.etZucc.)Maxim.)、灰毛猕猴桃(A.cinerascensC.F.Liang)、楔叶猕猴桃(A.fasciculoidesvar.cuneataC.F.Liang)和簇花猕猴桃(A.fasciculoidesC.F.Liang)为江西新分布。江西猕猴桃属植物区系特征表现在:(1)种类丰富;(2)特有现象较明显;(3)多型性突出;(4)地理成分复杂,以中国特有分布式样为主;(5)种间、种内分化较强烈;(6)与邻近地区猕猴桃属植物的关系密切。还对江西猕猴桃属植物的分布与自然生境的关系进行了探讨。

猕猴桃(Actinidia Lindl.)叶片与果实维生素C含量的相关性研究

以猕猴桃属中华猕猴桃(Actinidia chinensis)32个品种和1个种间杂交后代群体为研究对象,对猕猴桃属植物叶片与果实维生素C含量的相关性进行了研究。结果表明,在中华猕猴桃种内水平上,幼果与成熟果实的果肉维生素C含量间存在极显著的正相关关系;在种间杂交后代群体中成熟叶片和成熟果实的维生素C含量存在极显著正相关关系,为利用早期相关性状开展猕猴桃育种的可行性提供了理论依据。此外,对15个常见中华猕猴桃品种的果实维生素C含量进行了多重比较,为人工杂交时的亲本选择提供了依据。

猕猴桃细菌溃疡病(Actinidia bacterial canker)病原细菌鉴定

对四川省苍溪县猕猴桃的细菌病害进行系统鉴定表明,该病属细菌溃疡病,其病原细菌为 Pseudomonas syringae Pv.actinidea。病原细菌的鉴定属国内首次报导.

中华猕猴桃（Actinidia Chinensis）雌雄异株性状变异的研究

通过２ａ调查，发现了介于中华猕猴桃雌株与雄株之间的中间类型，但该类型数量稀少，在野生群体中只占０．５％左右。雌雄异株性状的变异可以从雌株、雄株以及中间类型的花器发育水平上体现。雌花的雌蕊可育，但花粉没有生活力；雄花雌蕊败育，但花粉正常；而中间类型花朵的雌蕊部分发育，而且花粉也有生活力。仅在雌株与中间类型上可以见到明显的“柱头一花柱”结构，但二者在柱头表面乳突的密度与发育水平上显著不同。中间类型花朵的柱头上乳突稀少，而且部分萎陷；花粉粒能在其柱头上发芽，但大多数花粉管不能伸入柱头组织。中间类型的发现不仅对研究雌雄异株性状的演化有一定意义，而且也为培育中华猕猴桃雌雄同株新品种奠定了基础。

赣中、北地区中华猕猴桃(Actinidia chinensis Planch.)病害调查与鉴定

经初步调查鉴定我省赣中、北地区中华猕猴桃(Actinidia chinensis Planch.)的病害有13种。其中真菌性病害11种,线虫病害、生理性病害各1种.

A high-quality Actinidia chinensis(kiwifruit)genome

Actinidia chinensis(kiwifruit)is a perennial horticultural crop species of the Actinidiaceae family with high nutritional and economic value.Two versions of the A.chinensis genomes have been previously assembled,based mainly on relatively short reads.Here,we report an improved chromosome-level reference genome of A.chinensis(v3.0),based mainly on PacBio long reads and Hi-C data.The high-quality assembled genome is 653 Mb long,with 0.76%heterozygosity.At least 43%of the genome consists of repetitive sequences,and the most abundant long terminal repeats were further identified and account for 23.38%of our novel genome.It has clear improvements in contiguity,accuracy,and gene annotation over the two previous versions and contains 40,464 annotated protein-coding genes,of which 94.41%are functionally annotated.Moreover,further analyses of genetic collinearity revealed that the kiwifruit genome has undergone two whole-genome duplications:one affecting all Ericales families near the K-T extinction event and a recent genus-specific duplication.The reference genome presented here will be highly useful for further molecular elucidation of diverse traits and for the breeding of this horticultural crop,as well as evolutionary studies with related taxa.

Differential regulation of the anthocyanin profile in purple kiwifruit(Actinidia species)

Anthocyanins are a group of secondary metabolites that colour fruit and flowers orange,red,purple or blue depending on a number of factors,such as the basic structure,co-pigmentation,metal ion complexation and vacuolar pH.The biosynthesis of anthocyanin is regulated at the transcriptional level by a group of transcription factors,the MYB–bHLH–WD40(MBW)complex.In this study,the purple colouration in several kiwifruit(Actinidia)species was identified and characterised as red cyanidin-based and blue delphinidin-based anthocyanins.The differential pigmentation in the skin and flesh can be attributed to the differential ratio of cyanidin and delphinidin derivatives accumulated in the total anthocyanin profile.The expression of anthocyanin biosynthetic genes chalcone synthase(CHS),flavonoid 3-O-glucosyltransferase(F3GT),flavonoid 3′-hydroxylase(F3′H)and flavonoid 3′5′-hydroxylase(F3′5′H)is crucial for anthocyanin accumulation.However,the balance of expression of the F3′H and F3′5′H genes appears responsible for the ratio of cyanidin and delphinidin derivatives,while a lack of CHS,F3GT and MYB110 expression is responsible for a lack of total anthocyanins.The transcriptional regulation of the F3′H and F3′5′H promoters by the R2R3 MYB transcription factor MYB110 is markedly different in tobacco transient assays.When kiwifruit MYB10 or MYB110 are over-expressed in Actinidia chinensis both cyanidin-based and delphinidin-based anthocyanins are elevated,but F3′H and F3′5′H genes are not strongly correlated with MYB expression.These results suggest that the core kiwifruit anthocyanin pathway genes are dependent on characterised MYB transcription factors,while other regulatory proteins are more directly responsible for the expression of the F3′H and F3′5′H genes.

猕猴桃属植物狗枣子(Actinidia kolomikta(Maxim.&Rupr.)Maxim.)的生态地理分布及其植物地理学意义

作者认为狗枣子 (Actinidiakolomikta (Maxim .&Rupr.)Maxim .)是一个多型的、具有两个间断布区的适应于地带性针阔叶混交林生境的猕猴桃属植物。文中还根据狗枣子的生态地理分布特征 ,认为狗枣子的现代中国西南 - -东北亚间断分布的格局是东亚第三纪以来气候回旋变化的结果所造成的。狗枣子原始分布区 (中国西南高山 )受气候回旋变化的胁迫衍生出次生的东北亚分布区。由于气候的振荡变化 ,水平方向上原有的连续分布区逐渐断裂而形成现代的间断分布格局。据此文中还指出 。

Comprehensive evaluation of Actinidia arguta fruit based on the nutrition and taste:67 germplasm native to Northeast China

Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions of A.arguta were measured,and sensory attributes including olfactive intensity,juiciness,sweetness,sourness,and astringency were assessed.Cluster analysis was carried out based on mineral elements,and principal component analysis(PCA)was used for comprehensive score ranking.The result demonstrated that fruit weight ranged from 3.5 g to 24.2 g,SSC ranged from 11.94%to 20.56%,TAC ranged from 0.15%to 1.20%,and vitamin C ranged from 3.51 g/kg to 230.76 g/kg(fresh weight)among the tested samples.There were significant differences in sourness,sweetness,bitterness,and umami among the 67 accessions based on electronic tongue analysis,and this result was rapidly and objectively characterized by the sensory assessment.The dendrogram was obtained and clustered the accessions into two major clusters,and five principal components were extracted by PCA.Overall,the information provided by this study identified the 10 best germplasm resources for fresh-eating and processing fruits.It can provide theoretical reference for nutritional efficacy evaluation and food development of A.arguta.

Exogenous cytokinin application to Actinidia chinensis var. deliciosa ‘Hayward’ fruit promotes fruit expansion through water uptake

Exogenous application of a cytokinin-like compound forchlorfenuron(CPPU)can promote fruit growth,although often at the expense of dry matter(DM),an important indicator of fruit quality.Actinidia chinensis var.deliciosa‘Hayward’fruit are very responsive to CPPU treatments,but the mechanism underlying the significant fruit weight increase and associated decrease in DM is unclear.In this study,we hypothesised that CPPU-enhanced growth increases fruit carbohydrate demand,but limited carbohydrate supply resulted in decreased fruit DM.During fruit development,CPPU effects on physical parameters,metabolites,osmotic pressure and transcriptional changes were assessed under conditions of both standard and a high carbohydrate supply.We showed that CPPU increased fruit fresh weight but the dramatic DM decrease was not carbohydrate limited.Enhanced glucose and fructose concentrations contributed to an increase in soluble carbohydrate osmotic pressure,which was correlated with increased water accumulation in CPPU-treated fruit and up-regulation of water channel aquaporin gene PIP2.4 at 49 days after anthesis.Transcipt analysis suggested that the molecular mechanism contributing to increased glucose and fructose concentrations was altered by carbohydrate supply.At standard carbohydrate supply,the early glucose increase in CPPU fruit was associated with reduced starch synthesis and increased starch degradation.When carbohydrate supply was high,the early glucose increase in CPPU fruit was associated with a general decrease in starch synthesis but up-regulation of vacuolar invertase and fructokinase genes.We conclude that CPPU affected fruit expansion by increasing the osmotically-driven water uptake and its effect was not carbohydrate supply-limited.

Effects of Stored Pollens from Wild <i>Actinidia eriantha</i>Vines on Some Fruit Quality Traits

Our study was conducted to determine In vitro germination ability of pollens from 25 wild Actinidia eriantha genotypes after one year freeze storage, afterwards we examined fertilization ability of stored pollens of 8 genotypes selected according to In vitro test results from aforementioned 25 genotypes, and finally investigated effects of stored viable pollens from “MH67”, “MH55”, “MH48” and “MH45” genotypes on fruit quality characters of the female experimental plant “M3” as the main purpose. Non-pollinated “M3” kiwifruit plant was taken as control. We found that In vitro germination and fertilization ability of different stored pollen sources, and also fruit quality characters including dry matter, total sugar, titratable acid, vitamin C, total polyphenol, total flavonoid, chlorophyll (“a”, “b”, and total) and carotenoid contents except total soluble solid content were significantly different. MH67 and MH45 genotypes were evaluated as the most suitable pollenizers which can be recommended as new candidate cultivars because of long term storage ability and brought about desired fruit quality characters. They also will be investigated more at further breeding studies.