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981.
982.
The deregulated cross-talk between airway epithelial cells with subepithelial fibroblasts during inflammation drives the pathogenesis of asthma. Bioinformatics analysis and luciferase activity assay suggested that B cell lymphoma-2 (BCL2) and CXC ligand 12 (CXCL12) are potential targets of miR-23a. The aim of this study was to elucidate the effect of microRNA-23a (miR-23a) on BCL2, and CXCL12 in asthma. In E3 rats, miR-23a was upregulated in lung tissues after antigen-induced pulmonary inflammation during acute and chronic inflammation. Immunohistochemistry showed downregulation of BCL2 in the epithelium and of CXCL12 in subepithelial fibroblasts and smooth muscle cells. Treatment of isolated cells with miR-23a mimic or inhibitor modified the expression of BCL2 and of CXCL12 in the expected cell type-specific manner. Moreover, in epithelial cells, interleukin-4 upregulated miR-23a expression and thereby decreased the expression of BCL2, while increasing the caspase-3 expression, which was followed by apoptosis. In fibroblasts, the expression of miR-23a was increased by thymic stromal lymphopoietin (TSLP). Consequently, the CXCL12 expression was abrogated. The phosphorylation of CREB was also downregulated by TSLP through the action of miR-23a. This study describes a novel mechanism, where miR-23a is an important cell type-specific regulator for asthma-associated airway wall remodeling parameter. Thus, miR-23a may present a potential new target for the therapy of asthma.  相似文献   
983.
Nuclear factor-κB (NF-κB) signaling is involved in regulating a great number of normal and abnormal cellular events. However, little is known about its role in ovarian follicular development. In this study, we found NF-κB signaling is activated during the transition from secondary to antral follicles. We generated active NF-κB mice and found that antral follicular numbers were higher than wild-type ovaries. Activation of NF-κB signaling could enhance granulosa cell proliferation and regress granulosa cell apoptosis of mouse ovarian follicles. Higher follicle-stimulating hormone receptor (FSHR) and luteinizing hormone/choriogonadotropin receptor expressions were observed in active NF-κB ovaries compared to wild type. Furthermore, we confirmed that NF-κB signaling was indeed involved in the granulosa cell viability and proliferation through FSHR using COV434 cell line. This is the first experimental evidence that NF-κB signaling is implicated in the control of follicular development through FSHR and its corresponding target molecules, which might be achieved by targeting proliferation and apoptosis in follicular granulosa cells.  相似文献   
984.
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986.
Xiao  Jun  Liu  Bao  Yao  Yingyin  Guo  Zifeng  Jia  Haiyan  Kong  Lingrang  Zhang  Aimin  Ma  Wujun  Ni  Zhongfu  Xu  Shengbao  Lu  Fei  Jiao  Yuannian  Yang  Wuyun  Lin  Xuelei  Sun  Silong  Lu  Zefu  Gao  Lifeng  Zhao  Guangyao  Cao  Shuanghe  Chen  Qian  Zhang  Kunpu  Wang  Mengcheng  Wang  Meng  Hu  Zhaorong  Guo  Weilong  Li  Guoqiang  Ma  Xin  Li  Junming  Han  Fangpu  Fu  Xiangdong  Ma  Zhengqiang  Wang  Daowen  Zhang  Xueyong  Ling  Hong-Qing  Xia  Guangmin  Tong  Yiping  Liu  Zhiyong  He  Zhonghu  Jia  Jizeng  Chong  Kang 《中国科学:生命科学英文版》2022,65(9):1718-1775
Science China Life Sciences - Bread wheat (Triticum aestivum L.) is a major crop that feeds 40% of the world’s population. Over the past several decades, advances in genomics have led to...  相似文献   
987.
Chen  Zhe  Bao  Linlin  Zhu  Bin  Fu  Hua  Zhu  Shuangli  Ji  Tianjiao  Xue  Ying  Liu  Chuan  Wang  Xurong  Li  Fengdi  Lv  Qi  Qi  Feifei  Yu  Pin  Deng  Wei  Xu  Wenbo  Qin  Chuan  Liu  Hongrong  Jin  Qi 《中国科学:生命科学英文版》2022,65(12):2517-2526
Science China Life Sciences - Enterovirus A71 (EV-A71) causes major outbreaks of hand, foot, and mouth disease (HFMD) in many countries, most frequently affecting children, and a small proportion...  相似文献   
988.
Fan  Ziyao  Liu  Zhiguo  Xu  Kui  Wu  Tianwen  Ruan  Jinxue  Zheng  Xinmin  Bao  Shideng  Mu  Yulian  Sonstegard  Tad  Li  Kui 《中国科学:生命科学英文版》2022,65(2):362-375
Science China Life Sciences - Beef and mutton production has been aided by breeding to integrate allelic diversity for myostatin (MSTN), but a lack of diversity in the MSTN germplasm has limited...  相似文献   
989.
目的探讨吴茱萸碱对破骨细胞分化与骨吸收功能的调控及对骨质疏松症的治疗作用。 方法取小鼠原代骨髓来源巨噬细胞分别给予0、10、20、50、100、200 μmol/L吴茱萸碱处理,CCK8检测细胞活力;然后利用原代骨髓来源巨噬细胞给予小鼠重组可溶性核因子κB受体活化因子配体与集落刺激因子行破骨细胞分化诱导,分别给予20与50 μmol/L吴茱萸碱干预。抗酒石酸酸性磷酸酶(TRAP)染色检测破骨细胞形成能力,荧光定量PCR分析破骨细胞分化相关基因表达,免疫荧光检测F肌动蛋白(F-actin)形成,扫描电镜观察破骨细胞骨吸收能力。7月龄C57BL/6小鼠灌胃给予100与200 mg/kg吴茱萸碱,给药3个月后Micro-CT检测小鼠骨密度与骨质量。采用单因素方差分析和t检验进行统计学分析。 结果CCK8结果显示,与对照组相比,给予10、20、50、100 μmol/L吴茱萸碱处理后细胞活力无明显变化,差异无统计学意义(P > 0.05);而给予200 μmol/L吴茱萸碱的细胞活力下降(100.64±0.18比47.54±5.58),差异具有统计学意义(P < 0.01)。与对照组相比,20 μmol/L吴茱萸碱的TRAP染色阳性细胞数[(200.57±28.35)比(142.29±19.21)个]、Trap (1.00±0.13比0.55±0.16)、组织蛋白酶K(Ctsk) (1.01±0.17比0.59±0.11)mRNA水平、骨吸收面积比(1.00±0.15比0.79±0.19)均减少,差异有统计学意义(P < 0.05)。与对照组相比,50 μmol/L吴茱萸碱的TRAP阳性细胞数[(200.57±28.35)比(112.71±12.18)个]、Trap (1.00±0.13比0.46±0.17)、Ctsk(1.01±0.17比0.49±0.12)、树突状细胞-特异性跨膜蛋白(DC- Stamp) (1.00±0.10比0.55±0.14)、c-Fos (1.01±0.10比0.58±0.14)、活化T细胞核因子c1 (Nfatc1) (1.00±0.10比0.59±0.14)、H+转运ATP酶v0亚基d2 (Atp6v0d2)的mRNA表达(1.00±0.10比0.59±0.18)、F-actin数量[(165.00± 18.50)比(98.33±21.15)个]和骨吸收面积比(1.00±0.15比0.62±0.10)均降低,差异有统计学意义(P < 0.05)。Micro-CT结果显示,与生理盐水组相比,100 mg/kg吴茱萸碱组小鼠骨密度有一定升高[(0.19±0.03)比(0.21±0.01)g/cm3],但差异无统计学意义(P > 0.05);与生理盐水组相比,200 mg/kg吴茱萸碱组小鼠胫骨的骨密度[(0.19±0.03)比(0.23±0.01)g/cm3]、骨体积比[(9.79±1.39)﹪比(11.62±1.18)﹪]、骨小梁数量[(2.43±0.29)比(3.08±0.43)/mm]上升,骨小梁分离度[(0.44±0.06)比(0.27±0.05)mm]下降,差异具有统计学意义(P < 0.05)。 结论吴茱萸碱通过抑制破骨细胞分化与骨吸收功能延缓小鼠骨量丢失。  相似文献   
990.
Male-sterile plants are used in hybrid breeding to improve yield in soybean (Glycine max (L.) Merr.). Developing the capability to alter fertility under different environmental conditions could broaden germplasm resources and simplify hybrid production. However, molecular mechanisms potentially underlying such a system in soybean were unclear. Here, using positional cloning, we identified a gene, MALE STERILITY 3 (MS3), which encodes a nuclear-localized protein containing a plant homeodomain (PHD)-finger domain. A spontaneous mutation in ms3 causing premature termination of MS3 translation and partial loss of the PHD-finger. Transgenetic analysis indicated that MS3 knockout resulted in nonfunctional pollen and no self-pollinated pods, and RNA-seq analysis revealed that MS3 affects the expression of genes associated with carbohydrate metabolism. Strikingly, the fertility of mutant ms3 can restore under long-dconditions. The mutant could thus be used to create a new, more stable photoperiod-sensitive genic male sterility line for two-line hybrid seed production, with significant impact on hybrid breeding and production.  相似文献   
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