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131.
Jiang J  Li J  Xu Y  Han Y  Bai Y  Zhou G  Lou Y  Xu Z  Chong K 《Plant, cell & environment》2007,30(6):690-699
Jasmonic acid (JA) is a well-known defence hormone, but its biological function and mechanism in rice root development are less understood. Here, we describe a JA-induced putative receptor-like protein (OsRLK, AAL87185) functioning in root development in rice. RNA in situ hybridization revealed that the gene was expressed largely in roots, and a fusion protein showed its localization on the plasma membrane. The primary roots in RNAi transgenic rice plants meandered and curled more easily than wild-type (WT) roots under JA treatment. Thus, this gene was renamed Oryza sativa root meander curling (OsRMC). The transgenic primary roots were shorter, the number of adventitious roots increased and the number of lateral roots decreased as compared to the WT. As well, the second sheath was reduced in length. Growth of both primary roots and second sheaths was sensitive to JA treatment. No significant change of JA level appeared in the roots between the transgenic rice line and WT. Expression of RSOsPR10, involved in the JA signalling pathway, was induced in transgenic rice. Western blotting revealed OsRMC induced by JA. Our results suggest that OsRMC of the DUF26 subfamily involved in JA signal transduction mediates root development and negatively regulates root curling in rice.  相似文献   
132.
超声对胃蛋白酶,胰蛋白酶,过氧化氢酶作用的研究   总被引:3,自引:0,他引:3  
以胃蛋白酶,胰蛋白酶,过氧化氢酶溶液在超声处理下的酶活变化为指标研究超声对蛋白质作用的机理和影响因素。结果表明超声对蛋白质的破坏程度随着功率的升高或处理时间的延长而增加;三种酶在超声作用下酶活变化形式和程度各不同;浓度是影响超声对酶作用效果的一个重要因素,可通过调整酶溶液浓度来减少酶所受到的破坏程度。自由基清除剂甘露醇和非离子表面活性剂吐温-80可以对酶活在超声作用下起到一定的保护作用,说明自由基和超声空穴是超声破坏酶结构的重要机理,研究结果同时表明对于不同的酶,超声的破坏作用可能有不同的发挥主导作用机理。  相似文献   
133.
Rhizoctonia solani and Phytophthora capsici are two of the most destructive phytopathogens occurring worldwide and are only partly being managed by traditional control strategies. Fluorescent Pseudomonas isolates PGC1 and PGC2 were checked for the antifungal potential against R. solani and P. capsici. Both the isolates were screened for the ability to produce a range of antifungal compounds. The results of this study indicated the role of chitinase and β-1,3-glucanase in the inhibition of R. solani, however, antifungal metabolites of a non-enzymatic nature were responsible for inhibition of P. capsici. The study confirmed that multiple and diverse mechanisms are adopted by the same antagonist to suppress different phytopathogens, as evidenced in case of R. solani and P. capsici.  相似文献   
134.
Gap junctions are clusters of intercellular channels that are associated with embryonic development and neural signaling. Innexins, invertebrate gap junction proteins, have been identified in Drosophila and Caenorhabditis. Here, we report the isolation and characterization of two novel members of the insect innexin family, Bm inx2 and Bm inx4, from embryos of the silkworm, Bombyx mori, during the germ-band formation stage. Bm inx2 is a single copy gene with one exon, while Bm inx4 is a single copy gene with four exons and three introns. The predicted proteins show structural similarities with other innexin family members, including four transmembrane (TM) domains, two extracellular loops (ELs), one cytoplasmic loop (CL), and typical conserved amino acids. Bm inx2 is phylogenetically orthologous to the other insect inx2 genes, but Bm inx4 is not orthologous to any known innexin including Dm inx4. Interestingly, Northern blotting and in situ hybridization showed that Bm inx2 was variously expressed across all developmental stages and in various tissues, with high expression seen in the nervous system at the time of embryogenesis. In contrast, Bm inx4 was transiently expressed at the germ-band formation stage of embryogenesis, and was specifically expressed in the ovary and testis during the larval and pupal stages. The isolation and characterization of these novel genes should form the basis for further study of the functional events that occur during development and neuronal communication in B. mori.  相似文献   
135.
Finland blue fox (Alopex lagopus) has great reputation in pelt industry around the world for its large size and top-ranking fur quality; however, both the herd size and the average survival rate of purebred offspring are rather low in production systems in China. Surgical transfer of blue fox embryos was investigated as a means to increase the population fox and also as a possible means to conserve endangered canine species. The animals were chosen on the basis of synchrony in natural oestrus. During the reproductive season of blue fox, 59 embryos were flushed from 6 farmed donors 9-11 days after the first insemination, and 53 embryos were transferred surgically into the uteri of the 6 paired recipients with natural synchronized oestrous. Two of the recipients littered 46-49 days after embryo transfer; one gave birth to 7 pups and the other 1 pup. This report describes the first successful embryo transfer in the farmed blue fox in China.  相似文献   
136.
本文对31例非特异性阴道炎病人和31例正常人阴道微生物群进行定性、定量分析.结果表明,阴道炎病人的阴道乳杆菌的平均浓度明显低于正常人,而肠杆菌科、葡萄球菌、棒状杆菌、类杆菌属、支原体却明显增多,阴道炎病人未发现特异性病原体,菌群失调可能是其发病因素。乳杆菌为阴道正常优势菌,对改善阴道的微环境,防止条件致病菌引起的内源性感染具有重要的生理作用。  相似文献   
137.
Hyun SH  Lee GS  Kim DY  Kim HS  Lee SH  Kim S  Lee ES  Lim JM  Kang SK  Lee BC  Hwang WS 《Theriogenology》2003,59(7):1641-1649
In order to develop a culture system and recipient cytoplasm that could improve the developmental competence of somatic cell nuclear transfer (SCNT) embryos for successful cloning of pigs, we evaluated the effect of donor oocytes and in vitro maturation (IVM) media on maturation of oocytes and developmental competence of SCNT embryos. In Experiment 1, oocytes derived from sows or gilts were matured in two IVM media (TCM-199 versus NCSU-23) and maturation of oocytes was evaluated by the status of chromatin configuration, the diameter of matured oocytes, the thickness of the zona pellucida, and the size of the perivitelline space (PVS). Sow oocytes matured in TCM-199 (S-TCM group) and NCSU-23 (S-NCSU group) showed significantly higher (P<0.05) maturation rates (S-TCM and S-NSCU, 86+/-4 and 82+/-4%, respectively) when evaluated by metaphase-II status than the gilt oocytes matured in TCM-199 (G-TCM group, 71+/-3%) and in NCSU-23 (G-NCSU-23 group, 71+/-3%). Oocyte diameter, the thickness of the zona pellucida, and the perivitelline space of sow oocytes (S-TCM and S-NCSU) were larger than those of gilt oocytes (G-TCM and G-NCSU) after IVM (P<0.05). In Experiment 2, SCNT was performed, using in vitro-matured oocytes from each group as recipient cytoplasm and porcine fetal fibroblasts as karyoplasts. The reconstructed embryos were electrically fused and activated, and cleavage and blastocyst formation were monitored under a stereomicroscope. The total cell number of flattened blastocysts stained with 5 microM bisbenzimide on day 7 were counted. In addition, in vitro matured non-enucleated oocytes were also electrically activated (parthenogenetic activation) and pronuclear formation was monitored. No difference in pronuclear formation rate after parthenogenetic activation and fusion rate after SCNT was observed among experimental groups. A significantly higher cleavage rate (P<0.05) was observed in S-TCM (69+/-4%) when compared with only G-NCSU (58+/-4%), but not with G-TCM (60+/-4%) or S-NCSU (68+/-4%). The rate of blastocyst formation was significantly higher (P<0.05) in sow oocytes (24% in S-TCM and S-NCSU), when compared to that observed in G-TCM (15%), and G-NCSU (14%). When the same source of oocytes was used, there was no significant difference in rate of blastocyst formation in the two culture media. Total cell number of blastocysts were not significantly different among experimental groups. In conclusion, the present study clearly demonstrated that sow oocytes have a greater developmental competence than gilt oocytes, regardless of the maturation medium examined.  相似文献   
138.
Though various factors related to fluctuations in sleep duration have been identified, information remains limited regarding the correlates of short and long sleep duration among the Korean population. Thus, we investigated characteristics that could be associated with short and/or long sleep duration among middle-aged and elderly Koreans. A total of 84,094 subjects (27,717 men and 56,377 women) who participated in the Health Examinees Study were analyzed by using multinomial logistic regression models. To evaluate whether sociodemographic factors, lifestyle factors, psychological conditions, anthropometry results, and health conditions were associated with short and/or long sleep duration, odds ratios (ORs) and 95% confidence intervals (CIs) were estimated with sleep duration of 6–7 hours as the reference group, accounting for putative covariates. Regardless of sexual differences, we found that adverse behaviors and lifestyle factors including low educational attainment, unemployment, being unmarried, current smoking status, lack of exercise, having irregular meals, poor psychosocial well-being, frequent stress events, and poor self-rated health were significantly associated with abnormal sleep duration. Similarly, diabetes mellitus and depression showed positive associations with abnormal sleep duration in both men and women. Our findings suggest that low sociodemographic characteristics, adverse lifestyle factors, poor psychological conditions, and certain disease morbidities could be associated with abnormal sleep duration in middle-aged and elderly Koreans.  相似文献   
139.
DNA sequencing identifies common and rare genetic variants for association studies, but studies typically focus on variants in nuclear DNA and ignore the mitochondrial genome. In fact, analyzing variants in mitochondrial DNA (mtDNA) sequences presents special problems, which we resolve here with a general solution for the analysis of mtDNA in next-generation sequencing studies. The new program package comprises 1) an algorithm designed to identify mtDNA variants (i.e., homoplasmies and heteroplasmies), incorporating sequencing error rates at each base in a likelihood calculation and allowing allele fractions at a variant site to differ across individuals; and 2) an estimation of mtDNA copy number in a cell directly from whole-genome sequencing data. We also apply the methods to DNA sequence from lymphocytes of ~2,000 SardiNIA Project participants. As expected, mothers and offspring share all homoplasmies but a lesser proportion of heteroplasmies. Both homoplasmies and heteroplasmies show 5-fold higher transition/transversion ratios than variants in nuclear DNA. Also, heteroplasmy increases with age, though on average only ~1 heteroplasmy reaches the 4% level between ages 20 and 90. In addition, we find that mtDNA copy number averages ~110 copies/lymphocyte and is ~54% heritable, implying substantial genetic regulation of the level of mtDNA. Copy numbers also decrease modestly but significantly with age, and females on average have significantly more copies than males. The mtDNA copy numbers are significantly associated with waist circumference (p-value = 0.0031) and waist-hip ratio (p-value = 2.4×10-5), but not with body mass index, indicating an association with central fat distribution. To our knowledge, this is the largest population analysis to date of mtDNA dynamics, revealing the age-imposed increase in heteroplasmy, the relatively high heritability of copy number, and the association of copy number with metabolic traits.  相似文献   
140.
The enzyme HemK (or PrmC) is one of the first identified methyltransferases that modify glutamine. It methylates the highly conserved GGQ motif in class I release factors (RF1 and RF2) in Escherichia coli. HemK from Thermotoga maritima was over-expressed and crystallized in the presence of S-adenosylmethionine at 296 K using ammonium sulfate as the precipitant. X-ray diffraction data were collected to 2.5 A resolution from a native crystal. The crystal is orthorhombic, belonging to the space group I222 (or I2(1)2(1)2(1)), with unit-cell parameters of a = 104.24, b = 118.73, and c = 146.62 A. Two (or three) monomers of recombinant HemK are likely to be present in the crystallographic asymmetric unit, giving a V(M) of 3.62 A3 Da(-1) (or 2.41 A3 Da(-1)), with a solvent content of 62.7% (or 44.0%).  相似文献   
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