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851.
Díaz-Valencia JD Morelli MM Bailey M Zhang D Sharp DJ Ross JL 《Biophysical journal》2011,100(10):2440-2449
Microtubule (MT) length and location is tightly controlled in cells. One novel family of MT-associated proteins that regulates MT dynamics is the MT-severing enzymes. In this work, we investigate how katanin (p60), believed to be the first discovered severing enzyme, binds and severs MTs via single molecule total internal reflection fluorescence microscopy. We find that severing activity depends on katanin concentration. We also find that katanin can remove tubulin dimers from the ends of MTs, appearing to depolymerize MTs. Strikingly, katanin localizes and severs at the interface of GMPCPP-tubulin and GDP-tubulin suggesting that it targets to protofilament-shift defects. Finally, we observe that binding duration, mobility, and oligomerization are ATP dependent. 相似文献
852.
Construction of a high density integrated genetic map for cucumber (Cucumis sativus L.) 总被引:1,自引:0,他引:1
Zhang WW Pan JS He HL Zhang C Li Z Zhao JL Yuan XJ Zhu LH Huang SW Cai R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(2):249-259
The high-density consensus map was constructed based on the GY14 × PI 183967 map from an inter-subspecific cross and the extended
S94 × S06 map from an intra-subspecific cross. The consensus map was composed of 1,369 loci, including 1,152 SSR loci, 192
SRAP loci, 21 SCAR loci and one STS locus as well as three gene loci of fruit external quality traits in seven chromosomes,
and spanned 700.5 cM, of which 682.7 cM (97.5%) were covered by SSR markers. The average genetic distance and physical interval
between loci were 0.51 cM and ~268 kbp, respectively. Additionally, the physical position of the sequence-associated markers
aligned along the assembled cucumber genome sequence established a relationship between genetic maps and cucumber genome sequence
and to a great extent validated the order of markers in individual maps and consensus map. This consensus map with a high
marker density and well-ordered markers is a saturated and reliable linkage map for genetic analysis of cucumber or the Cucurbitaceae
family of plants. 相似文献
853.
Chloroplast phylogeographic patterns of Calligonum sect. Pterococcus (Polygonaceae) in arid Northwest China 下载免费PDF全文
To understand the impacts of past climatic change and geological events on the evolutionary history of Calligonum sect. Pterococcus, including C. aphyllum, C. rubicundum and C. leucocladum, a total of 128 individuals from 14 populations, mainly from arid Northwest China, were sampled. Two cpDNA intergenic spacer regions (rpl32‐trnL and ycf6‐psbM) were sequenced and 11 haplotypes were identified. Levels of genetic differentiation between populations was low in C. rubicundum (FST = 0.54317, p < 0.001) and C. aphyllum (FST = 0.55795), while much higher in C. leucocladum (FST = 0.95800, p < 0.001), possibly as an effct of differences in geographic distributions and habitats. Analysis of molecular variance (AMOVA) revealed that most of the total genetic variations occurred among species (72.97%). Among eleven identified haplotypes, only H1 and H2 were shared between C. aphyllum and C. rubicundum, while nine were private for one of the three species. The eleven identified haplotypes were divided into two major clades, but they did not yield three species‐specific lineages. Calligonum sect. Pterococcus therefore not appeared reciprocally monophyletic, more likely due to incomplete lineage sorting than hybridization. Mismatch distribution analysis suggested that only C. aphyllum has experienced recent demographic expansion. Divergence time among the 11 haplotypes was estimated at between 2.84 Ma and 0.06 Ma. Within the two clades, haplotype divergence began in early Pleistocene and mainly occurred during the middle to late Pleistocene and was most likely triggered by Quaternary climatic oscillations and increasing aridity of the region. 相似文献
854.
855.
摘要:【目的】本研究通过百日咳杆菌黏附素(PRN)基因的分段克隆表达及其在BALB/c小鼠的主动和被动免疫保护试验筛选PRN中的保护性抗原肽。【方法和结果】利用大肠杆菌进行PRN的完整蛋白、N端和C端多肽及其RI和RII区域多肽(双拷贝)的表达,命名为GST-PRN、GST-PN、GST-PC、GST-2PRI和GST-2PRII。Western blot检测证实5种表达产物均具有良好的反应原性。在主动免疫保护试验中,5种表达产物均能诱导小鼠产生较高的PRN抗体水平;当使用3 LD50的支气管败血波氏杆菌 相似文献
856.
Hormonal regulation of fruit set, parthenogenesis induction and fruit expansion in Japanese pear 总被引:2,自引:1,他引:2
The effects of applied gibberellins (GAs), GA1, GA3, GA4 and GA7 with a cytokinin, N-(2-chloro-4-pyridyl)-N′-phenylurea (CPPU) and indole-3-acetic acid (IAA) on fruit set, parthenogenesis induction and fruit expansion of a number
of Rosaceae species were assessed. These included Japanese pear cv. ‘Akibae’ (self-compatible) and cv. ‘Iwate yamanashi’ (a
seedless cultivar). Other Rosaceae species (Pyrus communis, Chaenomeles sinensis, Cydonia oblonga, and Malus pumila) were also investigated. GA4, GA7 and CPPU are very effective in inducing parthenocarpic fruit growth, whereas GA1, GA3 and IAA, have no ability to induce parthenogenesis in Japanese pear. GA4- and GA7-induced parthenocarpic fruit tended to be smaller in size, higher in flesh hardness, and showed advanced fruit ripening in
comparison to pollinated fruit and to parthenocarpic fruit induced by CPPU. GA4- and GA7-induced parthenocarpic fruit also had an increased pedicel length and fruit shape index and also showed a slight protrusion
of the calyx end. CPPU, GA4 and GA7 alone or combination with uniconazole were also active in inducing parthenogenesis in three other Rosaceae species, although
final fruit set was extremely low. GA1 was essentially inactive in promoting fruit expansion unlike the other bioactive GAs, whose effectiveness in promoting fruit
cell expansion was as follow: GA4 ≈ GA7 > GA3 > GA1. 相似文献
857.
858.
859.
Rui Cheng Xiaoman Zheng Yingmei Wang Xing Ma Xin Liu Wenjun Xu Mengyun Wang Yuanpeng Gao Xupeng Xing Chuan Zhou Hongzheng Sun Zekun Guo Fusheng Quan Jun Liu Song Hua Yongsheng Wang Yong Zhang Xu Liu 《中国科学:生命科学英文版》2022,65(11):2257-2268
Animal cloning can be achieved by somatic cell nuclear transfer(SCNT), but the resulting live birth rate is relatively low. We previously improved the efficiency of bovine SCNT by exogenous melatonin treatment or by overexpression of lysine-specific demethylase 4D(KDM4D) and 4E(KDM4E). In this study, we revealed abundant alternative splicing(AS) transitions during fertilization and embryonic genome activation, and demonstrated abnormal AS in bovine SCNT embryos compared with in vitro fertilized ... 相似文献