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XU Jia-qi AN Mei-ling YUAN Yue HAO Yi-fan WANG Xiu-wen ZHANG Min WEI Xiao-wei LI Hua WANG Ren-jun 《园艺学报》2021,36(12):2148-2158
AIM To investigate whether microRNA-9-5p (miR-9-5p) mediates sympathetic overactivity by targeting KCNN3 (potassium intermediate/small conductance calcium-activated channel, subfamily N, member 3) gene,which encoded small-conductance calcium-activated potassium channel 3 (SK3) protein, in paraventricular nucleus (PVN) of rats with type 2 diabetes mellitus (T2D). METHODS A rat model of T2D was established by high-fat diet combined with intraperitoneal injection of 30 mg/kg streptozotocin. The levels of miR-9-5p and KCNN3 mRNA in PVN were detected by real-time PCR. The relationship between KCNN3 and miR-9-5p was predicted by TargetScan. Recombinant adeno-associated virus (rAAV)-miR-9-5p or KCNN3 were bilaterally microinjected into the PVN to observe the changes in plasma glucose levels and sympathetic drive indicators. The number of FosB and SK3 positive cells was measured by immunofluorescence staining. The protein expression of SK3 was determined by Western blot. The relationship between KCNN3 and miR-9-5p were confirmed by cell transfection and dual-luciferase reporter assay. RESULTS Compared with the rats in diabetes control (DC) group, the blood glucose, sympathetic drive indexes and the level of miR-9-5p in PVN were significantly increased, while the SK3 expression in PVN was obviously reduced in the diabetes mellitus (DM) rats. After microinjecion of rAAV-miR-9-5p in PVN, the sympathetic drive indexes, blood glucose, and the number of FosB-positive cells were increased significantly, but the SK3 protein expression was significantly reduced (P <0.05). However, up-regulation of KCNN3 in PVN had the opposite effect. These responses were obviously enhanced in DM rats compared with DC rats. The results of cell transfection and dual-luciferase reporter assay demonstrated that miR-9-5p bound to the 3’-UTR of KCNN3 and inhibit its expression. CONCLUSION miR-9-5p was up-regulated in PVN of the rats with T2D, and it may mediate sympathoexcitation by targeting KCNN3 . 相似文献
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蒲公英染色体核型分析 总被引:2,自引:0,他引:2
蒲公英的染色体核型国内一直未见报道 ,通过对其中期染色体形态的研究 ,得知其核型为 2n =2M 1 6m 4sm 4st=2 6。 相似文献
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Pearl grafting: Tracking the biological origin of nuclei by straightforward immunological methods 下载免费PDF全文
Nelly Schmitt Frédéric Marin Jérôme Thomas Laurent Plasseraud Marina Demoy‐Schneider 《Aquaculture Research》2018,49(2):692-700
French Polynesia is renowned for the production of Tahitian black pearl. These gems are obtained by grafting a nucleus into the gonad of a receiving oyster together with a graft, i.e. a small section of mantle tissue of a donor oyster. This procedure initiates the formation of a pearl sack around the nucleus, and subsequently, the deposition of concentric layers of nacre. The nucleus plays a key‐role in pearl formation and its characteristics influence markedly the quality of the final product. As it is manufactured from mollusc shells, it contains a small percentage of organics. In the present paper, we used a set of biochemical techniques to characterize and compare the organic matrices from two types of nuclei that are currently used in French Polynesia: that from the freshwater mussel Amblema sp., and that from the pearl oyster Pinctada sp. To this end, we extracted the matrices from nuclei and performed FT‐IR, monodimensional electrophoresis, and enzyme‐linked immuno‐sorbent assay (ELISA). Our data show that the matrix associated with Amblema nuclei has a very different biochemical signature from that of Pinctada nuclei, a fact that may explain the improved tolerance of grafted oysters to nuclei of Pinctada origin. In the absence of complex physical methods of investigation, simple immunological techniques and FT‐IR performed on the extracted organic matrix are extremely reliable and effective for discriminating nuclei from these two sources. We assert that such techniques can be used as a diagnostic test to track unambiguously the biological origin of nuclei to avoid fraud. 相似文献
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研究三氯生对红白鲫的急性毒性和遗传毒性作用,为分析评价三氯生对鱼类的生态安全性提供相应的毒理学资料。试验在规格为58 cm×28 cm×36 cm的玻璃水族箱中进行,红白鲫体长6.8~7.5 cm。采用半静态染毒法,设置不同浓度梯度的三氯生染毒组以及空白对照组和二甲基亚砜溶剂对照组,分别进行为期96 h的急性毒性试验和14 d的遗传毒性试验,观察记录死亡数,统计血红细胞微核率和核异常率。三氯生对红白鲫的96 h LC50为1 111.9μg/L。TCS染毒处理14 d后,红白鲫红细胞核异常的情况明显增多,主要是细胞质中有1~2个微核,其他常见核异常为红细胞核质外凸、核质内凹及核内空泡化;空白对照组和溶剂对照组之间核异常比率无显著差异(P0.05),而三氯生暴露各浓度组(600.0、690.0、793.5μg/L)核异常比率均极显著高于对照组(P0.01),且呈现明显的剂量-效应关系。研究表明,三氯生对红白鲫具有潜在的遗传毒性,且毒性效应在特定条件下随着暴露浓度的增加而增强。 相似文献
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117AB自交系经在湛江冬播自交5代,不育株率已达75%~80%。其不育株转为可育的温度为18~20℃。由于湛江早春升温过快,花前处于18~20℃的日数少,不育株转育率低,进一步纯合及纯合后的繁殖难度较大。因此,拟利用昆明夏季的中温条件进行进一步纯合及繁殖。将117AB自交系在昆明进行春播(4月下旬),调查了不育株育性转换率及转育后的可育天数,并考察了其部分农艺性状。结果表明:昆明春播117AB自交系花期(7~8月)的平均温度在19.9℃左右,出现半不育和可育温度的频率达到68.9%,而湛江仅达到36.2%,昆明不育株的转育株率为60.9%,而湛江仅为32.5%,农艺性状也较好,由此认为昆明适合117AB自交系的进一步纯合及繁殖。 相似文献
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Juveniles of the Caribbean scallops Argopecten nucleus and Nodipecten nodosus were suspended in pearl nets at densities of 25%, 30% and 50% coverage of the bottom of the net (BC) during days. Additionally, adults of A. nucleus (>35 mm) were placed in lantern nets at densities of 40%, 50% and 65% BC during days. Stocking density affected the growth of animals, with higher growth rates obtained at the lower densities. Although the survival of the two scallops was not influenced at the densities studied, the 15-day net changes, and culture in water of <28 °C produced better survival of A. nucleus and N. nodosus respectively. Predators of the families Cymatiidae, Grapsidae, Portunidae, Majidae and Xanthidae were found in the culture nets of juvenile A. nucleus , but during the adult phase they were absent. Predators exhibited a dense-independent behaviour in relation to scallops. There was not any association between predator frequency and survival of A. nucleus . 相似文献
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AIM: To investigate the effect of hypothalamic arcuate nucleus(ARC) damaged by monosodium glutamate (MSG) on bone histomorphometry parameters in rats. METHODS: (1) Newborn SD rats of experimental group were hypodermically injected 10% MSG (4 g/kg BW) on the postnatal lst, 3rd, 5th, 7th, 9th day. Meanwhile, the newborn rats of the control group were given equal volume of normal saline and the rats after the postnatal 70th, 72th, 74th, 76th and 78th day were hypodermically injected 10% MSG (4 g/kg BW) as the MSG toxicity control group. After survivial for 160 days, all rats were killed. (2) Morphological methods were used to estimate the ARC neurons and the bone histomorphometry parameters. (3) Radioimmunoassay was used to measure the levels of the serum growth hormoen(GH), estradiol(E2) and testosterone(T). RESULTS: The number of the hypothalamic arcuate nucleus neurons, the levels of serum E2, T, GH and the %Tb·Ar, Tb·Th, Tb·N of proximal tibial metaphysis(PTM) significantly decreased, while Tb·Sp of proximal tibial metaphysis(PTM) significantly increased, and the osteoporotic alterations appeared obviously. All these changes did not appear in the rats of NS group and MSG toxicity control group. CONCLUSION: (1) The changes of the bone in MSG guoup rats are not the effect of the MSG toxicity on the bone directly. (2) The hypothalamic arcuate nucleus participates in the regulation of the bone metabolism. (3) ARC regulates bone metabolism via altering the functions of the hypothalamus-GH-IGF-1 axis and the hypothalamus-pituitary-gonal axis. 相似文献