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1.
Sixin Jiang Brigitte Heller Vincent S. Tagliabracci Lanmin Zhai Jose M. Irimia Anna A. DePaoli-Roach Clark D. Wells Alexander V. Skurat Peter J. Roach 《The Journal of biological chemistry》2010,285(45):34960-34971
Stbd1 is a protein of previously unknown function that is most prevalent in liver and muscle, the major sites for storage of the energy reserve glycogen. The protein is predicted to contain a hydrophobic N terminus and a C-terminal CBM20 glycan binding domain. Here, we show that Stbd1 binds to glycogen in vitro and that endogenous Stbd1 locates to perinuclear compartments in cultured mouse FL83B or Rat1 cells. When overexpressed in COSM9 cells, Stbd1 concentrated at enlarged perinuclear structures, co-localized with glycogen, the late endosomal/lysosomal marker LAMP1 and the autophagy protein GABARAPL1. Mutant Stbd1 lacking the N-terminal hydrophobic segment had a diffuse distribution throughout the cell. Point mutations in the CBM20 domain did not change the perinuclear localization of Stbd1, but glycogen was no longer concentrated in this compartment. Stable overexpression of glycogen synthase in Rat1WT4 cells resulted in accumulation of glycogen as massive perinuclear deposits, where a large fraction of the detectable Stbd1 co-localized. Starvation of Rat1WT4 cells for glucose resulted in dissipation of the massive glycogen stores into numerous and much smaller glycogen deposits that retained Stbd1. In vitro, in cells, and in animal models, Stbd1 consistently tracked with glycogen. We conclude that Stbd1 is involved in glycogen metabolism by binding to glycogen and anchoring it to membranes, thereby affecting its cellular localization and its intracellular trafficking to lysosomes. 相似文献
2.
农业生态系统中新物种引进的初步探讨 总被引:5,自引:0,他引:5
在现有的农业生态系统中,引进某些新物种,往往可以使整个系统的功能发生变化。如果新物种引进得当,则可产生良好的效果,系统功能得以改善,效益提高;反之,则会造成人力、物力、财力的损失,削弱系统的功能,甚至可能遗患无穷。因此,对农业生态系统中 相似文献
3.
The pollution of heavy metals in soil to the environment is becoming more and more serious, resulting in the reduction of crop production and the occurrence of medical accidents. In order to remove heavy metal ions from soil and reduce the harm of heavy metals to the environment, modified peanut shell was used to adsorb Cr3+ in this article. The effects of different adsorption conditions on the adsorption rate and adsorption capacity of Cr3+ on ZnCl2 modified peanut shell were studied, the best adsorption conditions were explored, and the relationship of kinetics, thermodynamics and adsorption isotherm properties of adsorption process were explored. The results showed that the optimum adsorption pH value, dosage, initial concentration, adsorption temperature and contact time of ZnCl2 modified peanut shell were 2.5, 2.5 g/L, 75 μg/mL, 25 °C and 40 min, respectively. The prepared materials were characterized and analyzed by scanning electron microscope (SEM) and X-ray diffraction (XRD) analyzer. It was concluded that the modified peanut shell had a good adsorption capacity to Cr3+. The kinetic study showed that the adsorption process of Cr3+ on peanut shell modified by zinc chloride was in accordance with the quasi-second-order kinetic model. The adsorption process belonged to exothermic reaction and belonged to spontaneous reaction process. In summary, it is proved that zinc chloride modified peanut shell can efficiently adsorb Cr3+, which can be used for the treatment of heavy metal wastes in industry, which is beneficial to environmental protection and avoid heavy metal pollution. 相似文献
4.
Guozhen Liu Changjie Yan Wenxue Zhai Ping He Jiang Yang Xiaobing Li Lihuang Zhu 《中国科学C辑(英文版)》1999,42(2):162-170
Homeobox genes, widely distributed among animal and plant kingdoms, play an important role in developmental process. Several homeobox conserved fragments were amplified by PCR and the flanking regions were also obtained by an LM-PCR procedure. Sequencing and Southern analysis showed that they belong to a homeobox gene family of rice. Six homeobox-containing fragments were mapped on the molecular linkage map of rice. They were located on chromosomes 3, 4 and 7 respectively. It is noteworthy that there are 4 homeobox fragments located on rice chromosome 3 and the result is also consistent with the comparative genomics between rice and maize. 相似文献
5.
Breeding bacterial blight-resistant hybrid rice with the cloned bacterial blight resistance gene Xa21 总被引:1,自引:0,他引:1
Zhai Wenxue Wang Wenming Zhou Yongli Li Xiaobing Zheng Xianwu Zhang Qi Wang Guoliang Zhu Lihuang 《Molecular breeding : new strategies in plant improvement》2002,8(4):285-293
The cloned bacterial blight (BB) resistance gene Xa21 was transferred into Minghui63, a widely used restorer line of indica hybrid rice in China, through an Agrobacterium-mediated system. Molecular and resistance analyses revealed that the Xa21 gene was integrated in the genomes of transgenic plants and their progeny inherited resistance stably. For the purpose of hybrid breeding, Xa21 transgenic homozygous restorer lines were selected through `within-lane' dosage comparison of hybridization signal in combination with PCR and resistance analyses. The selected transgenic restorer lines were then crossed with a commonly used sterile line, Zhenshan97A, to produce Xa21 transgenic hybrid rice, Shanyou63-Xa21. The hybrid rice plants with Xa21 displayed high broad-spectrum resistance to Xanthomonas oryzae pv. oryzae (Xoo) races and maintained elite agronomic characters of Shanyou63. The propagation of this BB-resistant hybrid variety with Xa21 will benefit rice production. 相似文献
6.
Shu CW Madiraju C Zhai D Welsh K Diaz P Sergienko E Sano R Reed JC 《Journal of biomolecular screening》2011,16(2):174-182
Autophagy is an evolutionarily conserved process for catabolizing damaged proteins and organelles in a lysosome-dependent manner. Dysregulation of autophagy may cause various diseases, such as cancer and neurodegeneration. However, the relevance of autophagy to diseases remains controversial because of the limited availability of chemical modulators. Herein, the authors developed a fluorescence-based assay for measuring activity of the autophagy protease, autophagin-1(Atg4B). The assay employs a novel reporter substrate of Atg4B composed of a natural substrate (LC3B) fused to an assayable enzyme (PLA(2)) that becomes active upon cleavage by this cysteine protease. A high-throughput screening (HTS) assay was validated with excellent Z' factor (>0.7), remaining robust for more than 5 h and suitable for screening of large chemical libraries. The HTS assay was validated by performing pilot screens with 2 small collections of compounds enriched in bioactive molecules (n = 1280 for Lopac? and 2000 for Spectrum? library), yielding confirmed hit rates of 0.23% and 0.70%, respectively. As counterscreens, PLA(2) and caspase-3 assays were employed to eliminate nonspecific inhibitors. In conclusion, the LC3B-PLA(2) reporter assay provides a platform for compound library screening for identification and characterization of Atg4B-specific inhibitors that may be useful as tools for interrogating the role of autophagy in disease models. 相似文献
7.
Teleconnection between the early immigration of brown planthopper (BPH) and El Nino/Southern Oscillation (ENSO) indices from January of two years previously to the current June was investigated to make long-term forecast. The teleconnection results were as follows: ENSO indices which were significantly correlated with the early immigration of BPH were primarily sea surface temperature anomalies (SSTA) in N3, N4 and N3.4 regions, accounting for 71.8% of the total. Significant ENSO indices from two years and one year before the immigration events had a proportion of about 84%, while those in the current year only accounted for 16.7%. There was significantly negative correlation between the early immigration of BPH and SSTA in each Nino region from two years before to the previous spring, whereas there was significantly positive correlation between these two factors during the period from the previous winter to the current spring. The significant correlation between the early immigration of BPH and SSTA in each Nino region in the last summer and autumn did not show any obvious tendencies. The relationship between the southern oscillation index (SOI) and the early immigration of BPH was opposite to that between the immigration and SSTA in each Nino region. The above mentioned significant ENSO indices were used as key factors to build forecasting models for the early immigration of BPH by step-wise multiple linear regression analysis. Finally, 12 integrated forecasting models were obtained, which could make predictions 3–27 months ahead and had a predictive accuracy of 88.9%. 相似文献
8.
9.
Verstreken P Koh TW Schulze KL Zhai RG Hiesinger PR Zhou Y Mehta SQ Cao Y Roos J Bellen HJ 《Neuron》2003,40(4):733-748
We describe the isolation and characterization of Drosophila synaptojanin (synj) mutants. synj encodes a phosphatidylinositol phosphatase involved in clathrin-mediated endocytosis. We show that Synj is specifically localized to presynaptic terminals and is associated with synaptic vesicles. The electrophysiological and ultrastructural defects observed in synj mutants are strikingly similar to those found in endophilin mutants, and Synj and Endo colocalize and interact biochemically. Moreover, synj; endo double mutant synaptic terminals exhibit properties that are very similar to terminals of each single mutant, and overexpression of Endophilin can partially rescue the functional defects in partial loss-of-function synj mutants. Interestingly, Synj is mislocalized and destabilized at synapses devoid of Endophilin, suggesting that Endophilin recruits and stabilizes Synj on newly formed vesicles to promote vesicle uncoating. Our data also provide further evidence that kiss-and-run is able to maintain neurotransmitter release when synapses are not extensively challenged. 相似文献
10.
Yueming Zhang Wenrui Zhang Lina Tao Jinghui Zhai Huan Gao Yanqing Song Xiaoyu Qu 《Journal of biochemical and molecular toxicology》2019,33(9)
Isoniazid (INH) is one of the most commonly used antituberculosis drugs, but its clinical applications have been limited by severe hepatic toxicity. Quercetin (Que), a natural flavonoid, has been proved to have many medicinal properties. This study aimed to clarify the possible protective effects of Que against INH‐induced hepatotoxicity using HepG2 cells. Our results indicated that Que significantly increased cell viability, superoxide dismutase, and GSH levels, while decreased alanine aminotransferase/aspartate aminotransferase levels. Besides, Que significantly abrogated INH‐induced cell apoptosis by upregulating the expression levels of Bcl‐2 and decreasing the levels of Bax, cleaved caspase‐3, and cleaved caspase‐9. Furthermore, Que obviously reversed the inhibition of INH on Sirtuin 1 (SIRT1) expression and extracellular signal‐regulated kinase (ERK) phosphorylation. Next, the SIRT1 inhibitor EX527 blocked the enhancement of Que upon ERK phosphorylation. Notably, EX527 partially abolished the beneficial effects of Que. In brief, our results provided the first evidence that Que protected against INH‐induced HepG2 cells by regulating the SIRT1/ERK pathway. 相似文献