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941.
Paraoxonase is an HDL-associated enzyme that plays a preventive role against oxidative stress, which is thought to contribute
to cancer development. PON1 activity varies widely among individuals, which is in part related to two common nonsynonymous
polymorphisms in the PON1 gene (Q192R and L55M). The polymorphisms in PON1 have been implicated in cancer risk. However, results
from the studies to date have been conflicting. To clarify the association, a meta-analysis was performed for 7,073 cases
and 9,520 controls from 25 published case–control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used
to assess the strength of the association. Significant associations between PON1-L55M but not Q192R polymorphism and total
cancer were observed from all the comparisons. In stratified analyses, PON1-55M allele was a risk factor for breast cancer.
Similarly, increased risk was observed for prostate cancer (OR = 1.18, 95% CI: 1.01–1.36, P
heterogeneity = 0.260) and Caucasian population (OR = 1.18, 95% CI: 1.02–1.38, P
heterogeneity = 0.1) of the LM genotype, compared with the LL genotype. For PON1-Q192R polymorphism, PON1-192R allele was a decreased risk
factor for cancer in the Asian group (RR vs QQ: OR = 0.61, 95% CI: 0.38–0.98, P
heterogeneity = 0.268; QR vs QQ: OR = 0.71, 95% CI: 0.52–0.96, P
heterogeneity = 0.130; RR + QR vs QQ: OR = 0.71, 95% CI: 0.53–0.95, P
heterogeneity = 0.135). Although some modest bias could not be eliminated, this meta-analysis suggests that the PON1-55M allele is a risk factor for the development of cancer, in particular for breast cancer. Future studies with larger sample
sizes are warranted to further evaluate these associations. 相似文献
942.
Peng Wang Yongzhong Xing Zhikang Li Sibin Yu 《Molecular breeding : new strategies in plant improvement》2012,29(4):903-913
To facilitate marker-assisted transfer of desirable genes for improvement of yield traits, we used a set of backcross recombinant
inbred lines (BRIL) derived from two elite parental lines, ‘Zhenshan97’ and ‘93-11’, to resolve a quantitative trait loci
(QTL) cluster for heading date and yield-related traits in rice. Four main-effect QTL (qHD6.1, qHD6.2, qHD7, and qHD8) and four epistatic QTL affecting heading date in the BRIL were detected in two experimental trials. The major QTL (qHD8) was confirmed in three heterogeneous inbred families (HIF) that segregated for this target region, and narrowed down to
a 20-kb segment in a large HIF-derived population. qHD8 was found to interact with qHD7 and had a pleiotropic effect responsible for heading date and yield components. To test usability of the identified QTL in
rice improvement, we further developed near-isogenic lines (NIL) containing one or more target genes by marker-assisted transfer
of ‘93-11’ alleles at qHD8, qHD7, and qHD6.1, and the GS3 gene for grain size into ‘Zhenshan97’. The pyramid line NIL(qHD8 + GS3) had higher yield potential, longer grains, and a more suitable heading date than ‘Zhenshan97’. Comparison of the NIL showed
existence of epistasis between alleles at different loci and background effect on qHD8, which are very important for pyramiding of desirable alleles at the target QTL. These results will be particularly useful
not only to understand the genetic basis of yield-related traits but also to improve the efficiency of marker-assisted selection
for favorable loci in rice breeding programs. 相似文献
943.
【目的】初生型Photorhabdus luminescens细菌产生两种胞内晶体蛋白CipA和CipB,为其共生的昆虫病原异小杆线虫提供营养。探索非共生的斯氏线虫对Cip蛋白的营养利用情况。【方法】在已构建重组Cip蛋白大肠杆菌表达体系的基础上,建立重组菌细胞与无菌斯氏SY-5线虫共培养系统,检测线虫的生长发育情况。【结果】Cip蛋白对目标线虫生长有显著支持作用:发育为成虫的比例达到65%-82%,雌虫的怀卵率为80%-95%,平均怀卵量为30-50粒,并显著降低各虫态的死亡率。【结论】Cip蛋白不仅为共生的异小杆线虫提供营养,亦能为斯氏线虫所利用。 相似文献
944.
Late-acting self-incompatibility in tea plant (<Emphasis Type="Italic">Camellia sinensis</Emphasis>)
The self-incompatibility of tea plant (Camellia sinensis (L.) O. Kuntze) was studied with the methods of aniline blue fluorescence assay and paraffin sections. The characteristics
of pollen tube elongation after hand pollination was analyzed in 4 tea cultivars, including ‘Keemenzhong’, ‘Longjing-changye’,
‘Fuding-dabaicha’ and ‘Yabukita’, under self-pollination and cross-pollination, respectively. Although there were some difference
among cultivars, pollen tubes elongated through the style and reach the ovary successfully at 48 h after pollination for both
cross- and self-pollen tubes in all the four cultivars of tea. Pollen tubes entered into the ovule micropyles, however, only
for cross-pollination, but not for self-pollination. Pollen tubes of selfing plants, failed in fertilizing, seemed have some
difficulties to enter the ovule. All of which indicated that the self-incompatibility of tea plant is a late-acting self-incompatibility
system (LSI) or an ovarian sterility (OS), in which the self incompatibility was due to none self pollen tube penetrating
into the ovule and no fertilization. 相似文献
945.
Ke-Jing Wang Xiang-Hua Li Tetsuro Yamashita Yoshihito Takahata 《Plant Systematics and Evolution》2012,298(1):1-7
The wild soybean (Glycine soja), which is the progenitor of cultivated soybean (Glycine max), is expected to offer more information about genetic variability and more useful mutants for evolutionary research and breeding
applications. Here, a total of 1,600 wild soybean samples from China were investigated for genetic variation with regard to
the soybean Kunitz trypsin inhibitor (SKTI). A new mutant SKTI, Tik, was identified. It was found to be a Tia-derived codominant allele caused by a transversion point mutation from C to G at nucleotide +171, leading to an alteration
of one codon (AAC → AAG) and a corresponding amino acid substitution (Asn → Lys) at the ninth residue. Upon examination of
this variant and others previously found in wild soybeans, it became clear that SKTI has undergone high-level evolutionary
differentiation. There were more abundant polymorphisms in the wild than in the cultivated soybean. 相似文献
946.
Weidong Zhang Huan Wang Zhangqin Yuan Genglei Chu Heng Sun Zilin Yu Huan Liang Tao Liu Feng Zhou Bin Li 《International journal of biological sciences》2021,17(5):1395
Mechanical loading can induce or antagonize the extracellular matrix (ECM) synthesis, proliferation, migration, and inflammatory responses of annulus fibrosus cells (AFCs), depending on the loading mode and level. Caveolin-1 (Cav1), the core protein of caveolae, plays an important role in cellular mechanotransduction and inflammatory responses. In the present study, we presented that AFCs demonstrated different behaviors when subjected to cyclic tensile strain (CTS) for 24 h at a magnitude of 0%, 2%, 5% and 12%, respectively. It was found that 5% CTS had positive effects on cell proliferation, migration and anabolism, while 12% CTS had the opposite effects. Besides, cells exposed to interleukin-1β stimulus exhibited an increase expression in inflammatory genes, and the expression of these genes decreased after exposure to moderate mechanical loading with 5% CTS. In addition, 5% CTS decreased the level of Cav1 and integrin β1 and exhibited anti-inflammatory effects. Moreover, the expression of integrin β1 and p-p65 increased in AFCs transfected with Cav1 plasmids. In vivo results revealed that moderate mechanical stimulation could recover the water content and morphology of the discs. In conclusion, moderate mechanical stimulation restrained Cav1-mediated signaling pathway and exhibited anti-inflammatory effects on AFCs. Together with in vivo results, this study expounds the underlying molecular mechanisms on the effect of moderate mechanical stimulation on intervertebral discs (IVDs) and may provide a new therapeutic strategy for the treatment of IVD degeneration. 相似文献
947.
948.
目的研究miR-106a-5p对鼻咽癌细胞SUNE2增殖和迁移的影响。
方法将体外培养的鼻咽癌细胞SUNE2分成对照组(细胞未做任何处理)、Anti-NC组(转染阴性对照抑制剂)、Anti-miR-106a-5p组(转染miR-106a-5p抑制剂)、后期实验另设Anti-miR-106a-5p-inhibitor+si-NC组(转染miR-106a-5p抑制剂、siRNA阴性对照)、Anti-miR-106a-5p-inhibitor+si-PTEN组(转染miR-106a-5p抑制剂、PTEN siRNA),采用Realtime PCR测定miR-106a-5p表达,MTT法检测增殖,Transwell小室检测细胞侵袭和迁移能力变化,用Western blot方法测定vimentin、E-cadherin蛋白表达。在线靶基因预测软件预测miR-106a-5p的靶基因可能为PTEN,双荧光素酶报告系统鉴定miR-106a-5p和PTEN的靶向关系。两组间比较用独立样本t检验,多组间比较采用单因素方差分析,组间两两比较采用LSD-t检验。
结果与正常鼻咽上皮细胞NP69比较,鼻咽癌细胞CNE-2、HK1、SUNE2中miR-106a-5p水平(1.00±0.11比1.84±0.13、2.19±0.14、2.87±0.25)升高,差异具有统计学意义(P < 0.05)。与对照组、Anti-NC组比较,Anti-miR-106a-5p组鼻咽癌细胞miR-106a-5p水平(1.00±0.10、0.99±0.12比0.76±0.08)降低,OD值(0.56±0.05、0.57±0.04比0.32±0.02),细胞侵袭数[(128.47±11.65)个、(129.84±10.93)个比(85.12±6.75)个],迁移数[(182.51±14.81)个、(180.68±17.64)个比(122.01±11.62)个],vimentin蛋白表达水平(0.84±0.09、0.82±0.07比0.30±0.05)降低,E-cadherin蛋白表达水平(0.29±0.04、0.28±0.05比0.76±0.08)升高,差异具有统计学意义(P均< 0.05)。与Anti-miR-106a-inhibitor+si-NC组比较,Anti-miR-106a-inhibitor+si-PTEN组细胞OD值(0.33±0.03比0.52±0.05)、侵袭数[(84.16±5.91)个比(105.79±8.63)个]、迁移数[(118.42±10.25)个比(164.28±12.05)个]、vimentin蛋白表达水平(0.34±0.06比0.68±0.05)均升高,E-cadherin蛋白表达水平(0.72±0.06比0.29±0.05)降低,差异具有统计学意义(P均< 0.05)。
结论miR-106a-5p可通过靶向调控PTEN抑制鼻咽癌细胞SUNE2增殖和迁移潜能。 相似文献
949.
Growth rate of the Kuruma prawn, Marsupenaeus japonicus is an important economic trait, with larger animals commanding higher market prices. To identify gene markers associated
with growth, a genetic map of a full-sib F2 intercross family of M. japonicus has previously been generated and quantitative trait loci (QTL) influencing weight, total length, and carapace length were
identified. In this study, amplified fragment length polymorphism (AFLP) markers associated with the major QTL region, contributing
16% to phenotypic variation, were characterized. Flanking sequence has been obtained and allelic variants responsible for
segregation patterns of these markers have been identified. The genomic sequence surrounding the AFLP band 7.21a, residing
under the QTL peak, contains a gene sequence homologous to the elongation of very long chain fatty acids-like (ELOVL) protein family. A full-length mRNA (ELOVL-MJ) encoding this protein was isolated from M. japonicus, representing both the first ELOVL gene in crustacea and the first candidate gene identified via QTL studies in crustacea. 相似文献
950.
Pectinase was immobilized on a sodium alginate support using glutaraldehyde and retained 66% activity. The optimal pH for
activity shifted from 3.0 to 3.5 after immobilization; however, the optimum temperature remained unchanged at 40°C. The immobilized
enzyme also had a higher thermal stability and reusability than the free enzyme, and retained 80% of initial activity after
11 batch reactions. 相似文献