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11.
P Oettgen KC Carter M Augustus M Barcinski J Boltax C Kunsch TA Libermann 《Genomics》1997,445(2):456-457
12.
【目的】为了解析油菜种子硫代葡萄糖苷性状的重要遗传位点及候选基因,【方法】本研究利用KN DH群体在冬性环境2015-2018连续4年的种子硫苷含量表型和KN 高密度SNP遗传连锁图谱,通过Wincart 2.5软件的符合区间作图法对甘蓝型油菜种子硫代葡萄糖苷含量进行QTL定位和潜在候选基因鉴定。【结果】共鉴定到47个硫苷含量QTL,单个QTL解释表型变异最大是qGC.16YL19-4(19.44%),解释表型变异最小的是qGC.15YL12-5(1.82%)。利用元分析的方法将初步鉴定的47个QTL整合为38个consensus QTL,其中7个consensus QTL(cqGC.A9-5、cqGC.A9-7、cqGC.A9-9、cqGC.C2-9、cqGC.C2-10、cqGC.C9-5和cqGC.C9-6)为环境稳定表达QTL,包括3个硫苷含量主效QTL(cqGC.A9-5、cqGC.C2-10和cqGC.C9-5)。在主效QTLcqGC.A9-5和cqGC.C9-5鉴定到3个候选基因BnaA09g05480D,BnaC09g05620D和BnaC09g05810D,其功能主要涉及了油菜硫苷生物合成途径中吲哚-3-乙醛肟(IAOx)的合成和将2-烷基-苹果酸异构化形成3-烷基-苹果酸酯,以及硫苷的转运与分配。【结论】本研究获得了油菜种子硫苷含量3个主效QTL及3个候选基因,该结果为硫苷含量相关基因的功能机械和优质油菜品种培育提供理论依据。 相似文献
13.
Morphology and coexistence of congeneric ectoparasite species: reinforcement of reproductive isolation? 总被引:1,自引:0,他引:1
ANDREA IMKOVÁ MARKÉTA ONDRAKOVÁ MILAN GELNAR SERGE MORAND 《Biological journal of the Linnean Society. Linnean Society of London》2002,76(1):125-135
Assuming that differences or similarities in morphology among congeneric parasite species living in the same habitat are not a random pattern, several hypotheses explaining morphological differences were tested: (i) reproductive isolation, (ii) niche restriction resulting from competition, and (iii) niche specialization. Congeneric monogenean (platyhelminth) ectoparasites parasitizing the gills of one host species were used as an ecological model. Morphometric distances of the attachment organ and morphometric distances of the copulatory organ between species pairs were calculated, Levin's niche size and Renkonen niche overlap indices were applied. Our results support the prediction that the function of niche segregation is to achieve reproductive isolation of related species in order to prevent hybridization (reinforcement of reproductive barriers). Parasite species living in the same niche differ greatly in the size of copulatory organ. Moreover, species coexistence is facilitated by an increase in morphometric distances of copulatory organ and niche centre distances. Our results also show that species living in overlapping niches have similar attachment organs, which supports the prediction that morphologically similar species have the same ecological requirements within one host and suggests small effects of interspecific competition for the evolution of morphological diversity of attachment organs. Specialist adaptations also seem to facilitate species coexistence and affect the niche distribution within host species. Parasite species that can colonize more than one host species, i.e. generalists, occupy more distant niches within host species than strictly host-specific parasites. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76, 125–135. 相似文献
14.
R. Yll J.S. Carrión L. Bonfiglio 《Palaeogeography, Palaeoclimatology, Palaeoecology》2006,237(1):32-39
Vegetation reconstruction based on pollen from coprolites of extinct spotted hyena (Crocuta crocuta spelaea, Goldfuss 1832) recovered from excavations carried out in 1998 at San Teodoro Cave (Sicily, Italy) supports previous indications of pre-Late Glacial conditions. Eight of the twelve coprolites analysed contained well-preserved pollen grains. There is a general similarity between the pollen contents from the coprolites but they show variability. They suggest a main vegetation type dominated by steppic taxa (Poaceae, Artemisia, Ephedra, Chenopodiaceae and Asteraceae) but also including arboreal taxa (Pinus and Cupressaceae). Low percentages of pollen of mesophilous woody taxa (Quercus, Betula, Abies, Alnus, Pistacia, among others) are noticeable, suggesting the existence of nearby refugia for temperate and Mediterranean vegetation. A reconstruction of the landscape, using the coprolite pollen record and other pollen records from Sicily and south Italy, shows the predominance, during the pre-Late Glacial, of a wooded steppe biome, with elements representing a variety of local environmental conditions. 相似文献
15.
Francesco Lescai Silvia Bonfiglio Chiara Bacchelli Estelle Chanudet Aoife Waters Sanjay M. Sisodiya Dalia Kasperavi?iūt? Julie Williams Denise Harold John Hardy Robert Kleta Sebahattin Cirak Richard Williams John C. Achermann John Anderson David Kelsell Tom Vulliamy Henry Houlden Nicholas Wood Una Sheerin Gian Paolo Tonini Donna Mackay Khalid Hussain Jane Sowden Veronica Kinsler Justyna Osinska Tony Brooks Mike Hubank Philip Beales Elia Stupka 《PloS one》2012,7(12)
Recent advances in genomics technologies have spurred unprecedented efforts in genome and exome re-sequencing aiming to unravel the genetic component of rare and complex disorders. While in rare disorders this allowed the identification of novel causal genes, the missing heritability paradox in complex diseases remains so far elusive. Despite rapid advances of next-generation sequencing, both the technology and the analysis of the data it produces are in its infancy. At present there is abundant knowledge pertaining to the role of rare single nucleotide variants (SNVs) in rare disorders and of common SNVs in common disorders. Although the 1,000 genome project has clearly highlighted the prevalence of rare variants and more complex variants (e.g. insertions, deletions), their role in disease is as yet far from elucidated.We set out to analyse the properties of sequence variants identified in a comprehensive collection of exome re-sequencing studies performed on samples from patients affected by a broad range of complex and rare diseases (N = 173). Given the known potential for Loss of Function (LoF) variants to be false positive, we performed an extensive validation of the common, rare and private LoF variants identified, which indicated that most of the private and rare variants identified were indeed true, while common novel variants had a significantly higher false positive rate. Our results indicated a strong enrichment of very low-frequency insertion/deletion variants, so far under-investigated, which might be difficult to capture with low coverage and imputation approaches and for which most of study designs would be under-powered. These insertions and deletions might play a significant role in disease genetics, contributing specifically to the underlining rare and private variation predicted to be discovered through next generation sequencing. 相似文献
16.
Fossil plants from the lower part of Xianshuihe Formation in the Lanzhou Basin, Gansu Province were studied. The flora contains 29 species, representing 20 genera and 12 families, which include Lauraceae ( Daphnogene ), Lardizabalaceae ( Akebia ), Berberidaceae ( Berberis ), Ulmaceae ( Planera, Ulmus, Zelkova ), Betulaceae ( Alnus, Carpinus ), Myricaceae( Myrica ), Salicaceae ( Populus, Salix), Myrsinaceae(Ardisia), Rosaceae ( Prunus, Sorbus, Sorbaria, Spiraea ), Leguminosae ( Gleditsia, Sophora), Anacardiaceae (Rhus), Caprifoliaceae(Viburnum). An analysisof the floristic elements and their foliar physiognomy shows that most members of the flora are deciduous broad-leaved trees or shrubs with a few evergreen shrubs. The most noteworthy species is Rhus turcomanica which was present in the Middle Eocene to Late Eocene of Central Asia (Kazakhstan,Turkmenistan). Generally, Rhus turcomanica occurred at the same beds as Palibinia, an extinctfossil plant whose presence indicates a subtropical dry climate. Another species, Sorbaria callicomifolia Kornilova was present from the Early Oligocene to Early Miocene of Central Asia (Kazakhstanand Turkmenistan). According to an analysis of spores and pollen, this flora contains over 20 species. It is predominated by the angiosperm pollen. There appeared Ephedripites and Nitrariaditeswhich were important elements in the dry area. Ephedripites was found from the Upper Cretaceous toEarly Tertiary. Nitrariadites occurred in the Late Miocene, whereas Rhus turcomanica and Sorbaria callicomifolia were both reported in the subtropical dry area from the Middle Eocene to Early Oligocene. The latest record of Rhus turcomanica is from the Middle Eocene to Early Oligocene of CentralAsia. The presence of this element in the lower part of Xianshuihe Formation may indicate that itsage is the latest stage of the Early Oligocene. 相似文献
17.
Chia-Chun Yu Shih-Ping Liu Jui-Ling Hsu John TA Hsu Konstantin V Kudryavtsev Jih-Hwa Guh 《Journal of biomedical science》2015,22(1)
Background
Hormone-refractory prostate cancer (HRPC), which is resistant to hormone therapy, is a major obstacle in clinical treatment. An approach to inhibit HRPC growth and ultimately to kill cancers is highly demanded.Results
KUD773 induced the anti-proliferative effect and subsequent apoptosis in PC-3 and DU-145 (two HRPC cell lines); whereas, it showed less active in normal prostate cells. Further examination showed that KUD773 inhibited tubulin polymerization and induced an increase of mitotic phosphoproteins and polo-like kinase 1 (PLK1) phosphorylation, indicating a mitotic arrest of the cell cycle through an anti-tubulin action. The kinase assay demonstrated that KUD773 inhibited Aurora A activity. KUD773 induced an increase of Cdk1 phosphorylation at Thr161 (a stimulatory phosphorylation site) and a decrease of phosphorylation at Tyr15 (an inhibitory phosphorylation site), suggesting the activation of Cdk1. The data were substantiated by an up-regulation of cyclin B1 (a Cdk1 partner). Furthermore, KUD773 induced the phosphorylation and subsequent down-regulation of Bcl-2 and activation of caspase cascades.Conclusions
The data suggest that KUD773 induces apoptotic signaling in a sequential manner. It inhibits tubulin polymerization associated with an anti-Aurora A activity, leading to Cdk1 activation and mitotic arrest of the cell cycle that in turn induces Bcl-2 degradation and a subsequent caspase activation in HRPCs. 相似文献18.
目的:探讨铅锌联合染毒对乳鼠颅骨成骨细胞增殖分化的影响。方法:分离并培养原代成骨细胞,加入不同浓度铅、锌培养48h,检测其对成骨细胞增殖的作用;用碱性磷酸酶试剂盒检测ALP活力。结果:在染铅48h后,当铅浓度≥10μmol/L时,细胞增殖功能下降(P<0.05);加锌干预48h后,铅+锌组细胞增殖功能均高于各自单独染铅组,其中铅(1μmol/L、10μmol/L)+锌(50μmol/L)组、铅(10)+锌(100)组与对照组间的差异具有统计学意义(P<0.05)。铅干预48h后,100μmol/L铅组的ALP活力显著下(P<0.05),给予锌干预的铅锌联合染毒组,各组ALP活力均有增加,其中铅(1μmol/L、10μmol/L)+锌(50μmol/L)组ALP活力均高于对照组,而铅(100μmol/L)+锌(50μmol/L)组ALP活力低于对照组,差异均有统计学意义(P<0.05)。结论:铅对成骨细胞有毒性作用,影响其增殖和分化功能;50μmol/L锌在一定程度上可以拮抗铅对成骨细胞增殖和分化功能的损伤,且对ALP活力的作用更显著,为铅中毒骨病的防治提供一定的科学依据。 相似文献
19.
【目的】解析油菜矮秆性状调控遗传位点及关键基因,为油菜株高性状改良和抗倒伏油菜品种选育奠定基础。【方法】利用矮秆油菜DW1分别与高秆油菜WH14和WH20进行正反交,探究F1代和F2代矮秆性状遗传规律。同时,利用BSA-seq技术对油菜DW1和WH20的F2分离群体中极端高秆和极端矮秆2个DNA混池测序并鉴定矮秆性状的显著关联区域和候选基因。【结果】(1)油菜DW1矮秆性状为质量性状,由1对不完全显性基因控制。(2)在A06染色体21.78—23.88 Mb鉴定到22个与矮秆性状显著关联区,其中置信区间最大为46.71 kb,区间最小为0.64 kb。(3)在A06染色体上显著关联区域鉴定到BnaA06g27050D、BnaA06g34100D、BnaA06g34810D、BnaA06g35080D和BnaA06g36480D,其功能涉及植物生长素调控和赤霉素信号转导。【结论】油菜DW1的矮秆性状属于质量性状,由1对不完全显性基因控制。A06染色体上的上21.78—23.88 Mb区域为矮秆性状显著关联区域,该区域包含5个候选基因,其功能与植物生长素和赤霉素信号转导相关。 相似文献
20.
烟青虫感染核型多角体病毒后围食膜的病变 总被引:3,自引:1,他引:3
昆虫的围食膜是衬在昆虫中肠内一种网状的结构,它可充作虫体抵御外来病原侵染的一道屏障。关于鳞翅目昆虫幼虫感染了昆虫病毒后围食膜的病变问题,国内外鲜有报道。尤锡镇和康慧娟(1985)曾以实验证明家蚕围食膜对核型多角体病毒有灭活作用,而且认为核型多角体病毒不能侵染和破坏围食膜。Derksen和Granados(1988)则证明染病幼虫的围食膜因不同杆状病毒(包括两种核型多角体病 相似文献