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991.
992.
Haoxuan Liu Xiaohui Zhang Ju Huang Jian-Qun Chen Dacheng Tian Laurence D Hurst Sihai Yang 《Genome biology》2015,16(1)
BackgroundSocial hymenoptera, the honey bee (Apis mellifera) in particular, have ultra-high crossover rates and a large degree of intra-genomic variation in crossover rates. Aligned with haploid genomics of males, this makes them a potential model for examining the causes and consequences of crossing over. To address why social insects have such high crossing-over rates and the consequences of this, we constructed a high-resolution recombination atlas by sequencing 55 individuals from three colonies with an average marker density of 314 bp/marker.ResultsWe find crossing over to be especially high in proximity to genes upregulated in worker brains, but see no evidence for a coupling with immune-related functioning. We detect only a low rate of non-crossover gene conversion, contrary to current evidence. This is in striking contrast to the ultrahigh crossing-over rate, almost double that previously estimated from lower resolution data. We robustly recover the predicted intragenomic correlations between crossing over and both population level diversity and GC content, which could be best explained as indirect and direct consequences of crossing over, respectively.ConclusionsOur data are consistent with the view that diversification of worker behavior, but not immune function, is a driver of the high crossing-over rate in bees. While we see both high diversity and high GC content associated with high crossing-over rates, our estimate of the low non-crossover rate demonstrates that high non-crossover rates are not a necessary consequence of high recombination rates.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0566-0) contains supplementary material, which is available to authorized users. 相似文献993.
994.
995.
Plk1 has been essentially described as a critical regulator of many mitotic events. However, increasing evidence supports the notion that its molecular functions are not restricted to the cell cycle. In particular, recent reports suggest the existence of a molecular and functional link between Plk1 and the mammalian target of rapamycin (mTOR) pathway, which controls cell growth and proliferation via the raptor-mTOR (TORC1) and rictor-mTOR (TORC2) protein complexes. Herein, we have identified rapamycin-insensitive companion of mTOR (Rictor), a core component of mTORC2, as a new Plk1 substrate and have shown that Plk1 phosphorylates Rictor at Ser1162 in vitro and in vivo. Surprisingly, cells expressing the unphosphorylatable mutant (S1162A) of Rictor did not show any effect on well characterized canonical PI3K-mTOR pathway. However, we found that cells expressing the unphosphorylatable form of Rictor have an elevated level of mSin1 isoform (mSin1.5). Considering that mSin1.5-containing mTORC2 was reported to associate with stress signaling, we propose that phosphorylation of Rictor at Ser1162 by Plk1 might be involved in a novel signaling pathway by regulating the mSin1.5-defined mTORC2. 相似文献
996.
997.
Li H Jin G Qin J Tian M Shi J Yang W Tan X Zhang X Zou L 《Histochemistry and cell biology》2011,136(5):515-526
During the central nervous system (CNS) development, radial glia cells (RGCs) play at least two essential roles, they contribute
to neuronal production and the subsequent guidance of neuronal migration, whereas its precise distribution and contribution
to cerebral cortex remains less understood. In this research, we used Vimentin as an astroglial marker and Sox2 as a neural
progenitor marker to identify and investigate RGCs in rat cerebral cortex at embryonic day (E) 16.5. We found that the Sox2+
progenitor cells localized in the germinal zone (GZ) of E16.5 cerebral cortex, ~95% Sox2+ cells co-localized with Vimentin+
or Nestin+ radial processes which extended to the pial surface across the cortical plate (CP). In vitro, we obtained RG-like
cells from E16.5 cerebral cortex on adherent conditions, these Sox2+ Radial glia (RG)-like cells shared some properties with
RGCs in vivo, and these Sox2+ RG-like cells could differentiate into astrocytes, oligodendrocytes and presented the radial
glia—neuron lineage differentiation ability. Taken together, we identified and investigated some characterizations and properties
of Sox2+ RGCs derived from E16.5 cerebral cortex, we suggested that the embryonic Sox2+ progenitor cells which located in
the cortical GZ were mainly composed of Sox2+ RGCs, and the cortex-derived Sox2+ RG-like cells displayed the radial glia—neuron
lineage differentiation ability as neuronal progenitors in vitro. 相似文献
998.
999.
Yue Xiao Yu Zhang Bin Jiang Dan Dan Liu Yan Juan Niu Tian Gui 《World journal of microbiology & biotechnology》2011,27(9):2147-2153
A new alkaline keratinase, which could kill Meloidogyne incognita (a root-knot nematode) was separated and purified from Bacillus sp. 50-3 in this study. The solid ammonium sulfate was selected to precipitate the enzyme and its proper adding mass was
also determined. After solid ammonium sulfate precipitation and liquid chromatography on DEAE-Sephadex-A50 column, there was
17.7-fold purification with a yield of 46.5%, as determined by azokeratin as substrate. The purification effect was determined
through SDS-PAGE and the molecular weight of the enzyme was found to be 27,423 Da by the MALDI-TOF-MS. When the second-stage
juveniles of Meloidogyne incognita were exposed to 50 μg/ml of keratinase solution, 98.5% of Meloidogyne incognita mortality rates were obtained compared to control after 24 h. Its simple purification step and high yield from the cheap
medium affords this keratinase great biotechnological potential, especially in controlling root-knot nematodes such as Meloidogyne incognita. To the best of our knowledge, this study is the first report that uses keratinase as a pesticide. 相似文献
1000.
A versatile and highly sensitive probe for Hg(II), Pb(II) and Cd(II) detection individually and totally in water samples 总被引:1,自引:0,他引:1
Zhou Y Tian XL Li YS Zhang YY Yang L Zhang JH Wang XR Lu SY Ren HL Liu ZS 《Biosensors & bioelectronics》2011,30(1):310-314
The detection of heavy metal ions using enzyme-linked immunosorbent assays (ELISA) has been reported by several research groups. However, highly sensitive and selective detection of total heavy metal ions using ELISA is a major technical limitation. Here we describe the development of a versatile and highly sensitive probe combining goat anti-mice IgG, colloidal gold nanoparticles (AuNPs) and horseradish peroxidase (HRP). We demonstrate the utility of this probe using three kinds of heavy metal complete antigens and three monoclonal antibodies (McAbs) in one ELISA system to establish a high-throughput screening protocol. The procedure was successfully applied to analysis of Hg(II), Pb(II) and Cd(II) individually and totally from different water samples. The sensitivities for the detection of Hg(II), Pb(II) and Cd(II) individually and totally are 27.4, 3.9, 15.8 and 18.2 nM, respectively. And all limit of detection (LODs) are lower than 1.2 nM. The recovery results obtained from the developed technique showed a good correlation (R2 = 0.983) with those from ICP-MS. The major advantage of the probe is the versatility and high sensibility. The probe could be potentially used, upon demand, as a sensitive and versatile detector for a broad range of applications. 相似文献