花生新品种邢花4号的选育

以8252为母本、白沙1016为父本杂交选育而成的花生新品种邢花4号,具有高产、早熟、抗逆性强、适应性广和适宜烘烤等特点,适宜在北方夏花生产区麦垄套种或夏直播.     

褐飞虱自噬相关基因NlATG4的表达与功能

ATG4是一种半胱氨酸蛋白酶,负责ATG8蛋白羧基末端的切割,在自噬体形成过程中发挥重要作用。本研究克隆得到褐飞虱ATG4基因（NlATG4）的cDNA全长序列（GenBank登录号:MF062502.1）。RT-qPCR分析结果表明,NlATG4基因在褐飞虱的若虫和成虫时期均有表达,1～2龄若虫的表达量最高,在其他发育阶段的表达量稍低。RNAi结果显示,在dsRNA注射后的第4d,靶标基因NlATG4的表达量显著下降（仅为dsGFP对照组的22%）,同时,NlATG4的RNA干扰导致虫体ATP含量显著降低,仅为1.0μmol/(L·mg蛋白-1),为对照组的25%;在注射后的第6d,dsNlATG4处理组的褐飞虱存活率出现显著降低,其脂肪体组织变得松散,大型脂滴（直径≥5.0μm）数量增多,类酵母共生菌周围泡状结构的界限基本消失;在注射后的第8 d,dsNlATG4处理的褐飞虱的存活率下降为36.7%,比dsGFP对照组的存活率下降53.3%。本研究表明靶向NlATG4基因的RNA干扰会破坏褐飞虱脂肪体的结构完整性和类酵母共生菌的微环境,影响脂类物质代谢和ATP含量,并导致褐飞虱存活...     

胡椒4-香豆酸：辅酶A连接酶Pn4CL基因的克隆及表达分析

根据胡椒4-香豆酸：辅酶A连接酶（4-coumarate:coenzyme A ligase, 4CL）基因的部分序列设计引物,运用RACE方法获得其家族成员的1个全长cDNA,命名为Pn4cl,长度2130 bp,开放阅读框1638 bp,编码545个氨基酸。预测Pn4CL分子量为59.57 kDa,理论等电点为5.70。该基因含有AMP-binding（AMP-binding enzyme）、CaiC[Acyl-CoA synthetase (AMP-forming) /AMP-acid ligaseⅡ]、PLN02246、AFD-class I等结合域,具有植物4CL所共有的保守结构域。系统进化分析表明,Pn4CL与北细辛的同源性最高,同时与木兰分支类植物的4CL聚类在一起,与菊分支的进化距离较近,与蔷薇分支的进化距离较远。亚细胞定位表明,该蛋白定位在细胞膜上。Real-time RT-PCR结果表明,该基因受外援激素SA和MeJA诱导表达,同时接种辣椒疫霉菌后,Pn4CL基因的表达量在抗/感2种胡椒中均出现先增加后减少的现象,并且在抗病种质中表达量较高。研究结果为Pn4CL的功能研究提供了理论依据。     

Verrucosamide,a Cytotoxic 1,4-Thiazepane-Containing Thiodepsipeptide from a Marine-Derived Actinomycete

A new cytotoxic thiodepsipeptide, verrucosamide (1), was isolated along with the known, related cyclic peptide thiocoraline, from the extract of a marine-derived actinomycete, a Verrucosispora sp., our strain CNX-026. The new peptide, which is composed of two rare seven-membered 1,4-thiazepane rings, was elucidated by a combination of spectral methods and the absolute configuration was determined by a single X-ray diffraction study. Verrucosamide (1) showed moderate cytotoxicity and selectivity in the NCI 60 cell line bioassay. The most susceptible cell lines were MDA-MB-468 breast carcinoma with an LD₅₀ of 1.26 µM, and COLO 205 colon adenocarcinoma with an LD₅₀ of 1.4 µM. Also isolated along with verrucosamide were three small 3-hydroxy(alkoxy)-quinaldic acid derivatives that appear to be products of the same biosynthetic pathway.     

Basal internode elongation of rice as affected by light intensity and leaf area

Short basal internodes are important for lodging resistance of rice(Oryza sativa L.).Several canopy indices affect the elongation of basal internodes,but uncertainty as to the key factors determining elongation of basal internodes persists.The objectives of this study were(1)to identify key factors affecting the elongation of basal internodes and(2)to establish a quantitative relationship between basal internode length and canopy indices.An inbred rice cultivar,Yinjingruanzhan,was grown in two split-plot field experiments with three N rates(0,75,and 150 kg N ha−1 in early season and 0,90,and 180 kg N ha−1 in late season)as main plots,three seedling densities(16.7,75.0,and 187.5 seedlings m−2)as subplots,and three replications in the 2015 early and late seasons in Guangzhou,China.Light intensity at base of canopy(Lb),light quality as determined from red/far-red light ratio(R/FR),light transmission ratio(LTR),leaf area index(LAI),leaf N concentration(NLV)and final length of second internode(counted from soil surface upward)(FIL)were recorded.Higher N rate and seedling density resulted in significantly longer FIL.FIL was negatively correlated with Lb,LTR,and R/FR(P<0.01)and positively correlated with LAI(P<0.01),but not correlated with NLV(P>0.05).Stepwise linear regression analysis showed that FIL was strongly associated with Lb and LAI(R2=0.82).Heavy N application to pot-grown rice at the beginning of first internode elongation did not change FIL.We conclude that FIL is determined mainly by Lb and LAI at jointing stage.NLV has no direct effect on the elongation of basal internodes.N application indirectly affects FIL by changing LAI and light conditions in the rice canopy.Reducing LAI and improving canopy light transmission at jointing stage can shorten the basal internodes and increase the lodging resistance of rice.     

Roles of protein phosphatase 4 in down-regulation of eNOS Ser633 phosphorylation induced by palmitic acid in human umbilical vein endotheli?al cells

AIMTo investigate the roles of protein phosphatase 4 (PP4) in down-regulation of endothelial nitric oxide synthase (eNOS) Ser633 phosphorylation induced by palmitic acid (PA). METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with PA at 25 μmol/L, 50 μmol/L, 100 μmol/L and 200μmol/L for 36 h, or treated with PA at 100 μmol/L for 12 h, 24 h, 36 h and 48 h. Protein phosphatase 2A (PP2A) family inhibitor fostriecin (FST, 20 nmol/L) or okadaic acid (OA, 5 nmol/L) was selected to pretreat the HUVECs for 30 min. Protein phosphatase 4 catalytic subunit (PP4c) siRNA or protein phosphatase 2A catalytic subunit (PP2Ac) siRNA was transfected into the HUVECs. The protein expression levels of of eNOS, PP4c and PP2Ac, as well as the level of eNOS Ser633 phosphorylation, were detected by Western blot. The intracellular nitric oxide (NO) content was measured by DAF-FM DA. RESULTS(1) Compared with control group, the levels of eNOS Ser633 phosphorylation were decreased in PA groups in which the HUVECs were treated with 25 μmol/L, 50 μmol/L, 100 μmol/L and 200 μmol/L PA for 36 h (P<0.05) and 100 μmol/L PA for 24 h, 36 h and 48 h (P<0.05). No significant difference in the level of total eNOS protein expression among all the groups was observed. (2) Compared with control group, both FST and OA pretreatment reversed the reduction of eNOS Ser633 phosphorylation (P<0.05) and the decrease in intracellular NO content (P<0.05) induced by PA. No significant difference in the level of total eNOS protein expression among all the groups was observed. (3) Compared with si-Control group, the PP4c protein expression was significantly reduced (P<0.05), while the level of eNOS Ser633 phosphorylation was significantly increased in si-PP4c group (P<0.05). Although the levels of PP2Ac protein expression declined significantly (P<0.05), the level of eNOS Ser633 phosphorylation remained unchanged in si-PP2Ac group. No significant differencein the level of total eNOS protein expression among all the groups was found. CONCLUSION PA significantly reduces the level of eNOS Ser633 phosphorylation and the content of NO in the HUVECs, which may be due to PA inducing the activation of the PP2A family member PP4 rather than PP2A.     

Sulodexide protects against hyperglycemia-induced retinal vascular injury via suppressing NOX4/NLRP3 pathway

AIM To investigate the effect of sulodexide (SDX) on high glucose-induced damage in retinal microvascular endothelial cells. METHODS (1) High-fat diet combined with intraperitoneal injection of streptozocin were used to induce type 2 diabetes mellitus (DM) followed by injection of saline or SDX in C57BL/6J male mice. Retinal microvascular leakage and density, and the protein levels of NLRP3 inflammasome-related proteins, zonula occludens-1 (ZO-1) and NADPH oxidase 4 (NOX4) were measured. (2) Human retinal microvascular endothelial cells (HRMECs) were treated with normal glucose or high glucose with or without SDX, and were further transfected with siRNA to knock down NOX4, or infected by adenovirus to over-express NOX4. The protein levels of ZO-1, VE-cadherin (VE-Cad), NOX4 and NLRP3 inflammasome-related proteins as well as the level of reactive oxygen species (ROS) were detected. RESULTS Treatment with SDX increased the protein level of ZO-1, attenuated retinal leakage and NLRP3 inflammasome activation, and enhanced the density of microvasculature and the number of ganglion cells in diabetic retinas. The protein levels of ZO-1 and VE-Cad were decreased, while the levels of NOX4, NLRP3 inflammasome-related proteins and ROS generation were increased in high glucose-treated HRMECs. Silencing of NOX4 inhibited high glucose-induced increases in NLRP3 inflammasome and ROS generation, and decreases in the protein levels of ZO-1 and VE-Cad. Over-expression of NOX4 significantly increased the levels of NLRP3 inflammasome-related proteins and ROS generation in HRMECs, and reduced the protein levels of ZO-1 and VE-Cad. Treatment with SDX partly reversed NOX4 over-expression-induced changes. CONCLUSION SDX alleviates hyperglycemia-induced retinal microvascular endothelial injury via inhibiting NOX4/ROS/NLRP3 pathways.     

Role of IP3R in LH-EGFR-induced mouse oocyte meiotic resumption

AIM: To explore the effect of inositol 1, 4, 5-trisposphate receptor (IP₃R) in luteinizing hormone-epidermal growth factor receptor (LH-EGFR)-induced oocyte meiotic resumption. METHODS: Models of mouse cumulus-oocyte complexs (COCs) culture and follicle culture in vitro were generated to study the effects of 2-aminoethyl diphenyl borate (2-APB) and heparin (IP₃R specific inhibitors) on LH/EGF-induced oocyte meiotic resumption and EGF-induced cumulus cell expansion. Real-time PCR was used to detect the mRNA expression of cumulus expansion-related factors. The changes of the intracellular calcium level were monitored using Fluo 3-AM, and the cGMP level was measured by ELISA. RESULTS: The inhibitors of IP₃R, 2-APB and heparin, dramatically reversed EGF-induced oocyte maturation (P<0.05) and decreased cGMP levels in COCs (P<0.05). In addition, 2-APB and heparin reversed EGF-induced cumulus expansion, and significantly inhibited EGF-induced cumulus expansion-related factor expression (P<0.05). The activation of IP₃R increased intracellular calcium level, and the study found that 2-APB and heparin dramatically reversed EGF-induced elevation of calcium level in cumulus cells (P<0.05). Follicular culture in vitro showed that 2-APB and heparin significantly reversed the LH-induced oocyte maturation (P<0.05). CONCLUSION: LH-EGFR signaling pathway increases calcium level in cumulus cells through IP₃R, resulting in meiotic resumption.