Effect of melatonin on visceral fat deposition,lipid metabolism and hepatic lipo-metabolic gene expression in male rats

Melatonin (MT) influences lipid metabolism in animals; however, the mechanistic effect of melatonin on liver fat and abdominal adipose deposition requires further clarity. In order to study the effects of melatonin on lipid metabolism, and hepatic fat and abdominal adipose deposition in animals, twenty Sprague–Dawley (SD) rats of 6 weeks of age with similar bodyweight were randomly divided into two groups: control (CTL) and MT-treated (10 mg/kg/day). During a 60-day experiment, food intake and bodyweight were measured daily and weekly respectively. At the end of treatment, blood samples were collected to collect plasma to quantify hormones and metabolic indicators of lipid metabolism. In addition, organ and abdominal adipose depots including liver, and omental, perirenal, and epididymal fat were weighed. Liver tissue was sampled for sectioning, long-chain fatty acid (LCFA) quantification, and gene chip and Real-time quantitative PCR (qPCR) analyses. The results showed that liver weight and index (ratio of liver weight to body weight) in MT group reduced by 20.69% and 9.63% respectively; omentum weight and index reduced by 59.88% and 54.93% respectively, and epididymal fat weight reduced by 45.34% (p = 0.049), relative to CTL. Plasma lipid indices, triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol (TC) with MT treatment decreased significantly compared with the control. Fat and 8 LCFA content in liver in MT group also decreased. Gene chip and qPCR demonstrated that there were 289 genes up-regulated and 293 genes down-regulated by MT. Further analysis found that the mRNA expression of lipolysis-related genes increased, while the mRNA expression of lipogenesis-related enzymes decreased (p < 0.05) with MT. This study concluded that melatonin greatly affected fat deposition, and hepatic LCFA supply and the expression of genes associated with lipogenesis and lipolysis.     

甘草总黄酮对高脂条件下罗非鱼肝损伤的保护作用

为了研究甘草总黄酮对高脂饲料造成的罗非鱼(Oreochromis niloticus)脂肪肝损伤是否具有保护作用,随机将180尾健康无伤罗非鱼分成6组,即对照组、高脂饲料模型组和4个不同浓度甘草总黄酮组(0.05、0.10、0.50、1.00 g·kg^-1甘草总黄酮),每组30尾。饲喂90 d后,采集罗非鱼各实验组肝,测定肝匀浆中超氧化物歧化酶(SOD)活性、还原型谷胱甘肽(GSH)活性、丙二醛(MDA)含量、甘油三酯(TG)含量、总胆固醇(TC)含量、总抗氧化能力(T-AOC)水平,Western blotting法检测肝中核转录因子-κB P65(NF-κB P65)和核转录因子-κB C-Rel (NF-κB C-Rel)蛋白表达水平,RT-PCR法测定肝中微粒体甘油三酸酯转移蛋白(MTTP)和载脂蛋白B100(ApoB100)基因表达情况。结果表明:与对照组相比,高脂饲料模型组罗非鱼肝匀浆中TG、TC、MDA含量极显著(P<0.01)升高,GSH活性、SOD活性、T-AOC水平均极显著(P<0.01)降低;MTTP和ApoB100 mRNA表达水平降低(P<0.01或P<0.05);Western blotting结果显示,NF-κB P 65和C-Rel蛋白表达水平升高。饲料中加入甘草总黄酮后,与高脂饲料模型组相比,罗非鱼肝中GSH活性、SOD活性、T-AOC水平不同程度提高,TC、TG、MDA含量和NF-κB P65、C-Rel蛋白表达水平不同程度降低,MTTP和ApoB100的mRNA表达水平升高,以0.50 g·kg^-1甘草总黄酮组效果较好。说明甘草总黄酮对于罗非鱼脂肪肝损伤具有一定的保护作用,可以缓解高脂饲料造成的脂肪肝损伤。     

火龙果节律钟输出基因HpGI的克隆与表达分析

节律钟输出基因GIGANTEA通过光周期途径促进植物开花,为研究火龙果GIGANTEA同源基因功能,应用RT-PCR克隆获得该基因的开放阅读框序列,命名为Hylocereus polyrhizus GIGANTEA (HpGI),GenBank登录号为MK609546。序列分析结果表明,HpGI开放阅读框长度为3537 bp,编码1178个氨基酸。系统进化分析显示,HpGI与甜菜BvGI、菠菜SoGI、丝石竹GpGI的分子进化距离较近。预测HpGI定位于细胞核,无信号肽和跨膜螺旋结构域,属于非分泌蛋白。基因表达分析结果表明,HpGI基因在茎和花芽中的表达量显著高于茎芽、果皮和根;相比对照,延长光周期处理8 d时,其表达量显著上调。推测HpGI基因可能通过光周期途径促进火龙果开花。     

甘蓝型油菜转录因子FUS3的克隆、表达分析及其与脂肪酸组分的关系

 为了探讨油菜转录因子FUS3的功能及其与脂肪酸组分的关系，从甘蓝型油菜湘油15中克隆到BnaFUS3基因的两个拷贝BnaA2.FUS3和BnaA6.FUS3。它们的CDS区序列分别长927bp和948bp，编码309和315个氨基酸，氨基酸序列变异多发生在C端。转录因子BnaA2.FUS3和BnaA6.FUS3属于含B3结构域的蛋白家族，是亲水性蛋白，无跨膜区，均是膜外蛋白。系统进化树分析表明，BnaA2.FUS3、BnaA6.FUS3两者都是BraFUS3和AtFUS3的同源基因。荧光定量PCR分析表明，BnaA2.FUS3在根、茎、叶、角果皮中均有表达，在种子中相对稳定表达，但在角果皮25d达到峰值；BnaA6.FUS3为种子特异表达，在种子35d达到峰值；两者在角果皮中表达量均呈“M”形趋势。分析脂肪酸积累规律与BnaFUS3表达关系发现，授粉30d后，BnaA2.FUS3和BnaA6.FUS3表达迅速升高，此时各脂肪酸也进入快速增长期；授粉后45d~50d时，两拷贝表达量变化较小，脂肪酸积累亦进入缓慢增长期，并趋于平稳。表明BnaFUS3在甘蓝型油菜的胚胎形成和发育中具有重要影响，对脂肪酸的合成和油脂积累起到重要作用。     

猪BLM基因N端、C端的克隆及其在不同组织与疾病中的表达分析

为探究猪BLM解旋酶N端、C端的结构功能及其在不同组织和疾病中的相对表达量，本研究采用RT-PCR技术扩增从江香猪BLM基因N端和C端，利用生物信息学软件对克隆所获序列进行分析，同时采用实时荧光定量PCR技术分析BLM基因在猪不同组织及病样中的表达差异。结果显示，试验成功克隆了从江香猪BLM基因N端1 025 bp和C端1 300 bp序列，与GenBank中猪BLM基因序列（登录号：NM_001123084.1）同源性为100%；生物信息学软件预测显示，猪BLM基因序列长度为4 316 bp，包含4 280 bp的开放阅读框，编码一个由1 426个氨基酸组成的多肽链；氨基酸序列比对发现，猪BLM基因氨基酸序列与牛的同源性最高（85%）；结构域预测表明，猪BLM基因有DEXDc、HELICc、RQC和HRDC 4个结构域；系统进化树分析表明，猪BLM基因与牛亲缘关系最近；实时荧光定量PCR结果显示，以心脏为对照，BLM基因在从江香猪各组织中均有表达，其中在睾丸中的相对表达量最高，其次为肺脏、肝脏、脾脏、心脏、肾脏、小肠和大肠，在睾丸和肺脏中的表达量均极显著高于其他组织（P<0.01）；BLM基因在患繁殖与呼吸道综合征猪肺脏、患白血病鸡肝脏和患鸭瘟鸭肝脏中的表达水平均极显著或显著高于正常组织（P<0.01；P<0.05），提示BLM基因的变化可能也会导致动物疾病的发生。本试验结果可为后续畜禽BLM解旋酶原核表达载体的构建及其在重大疾病的发生和预防等研究提供理论依据。     

Structure and expression analysis of the sucrose synthase gene family in apple

Sucrose synthases (SUS) are a family of enzymes that play pivotal roles in carbon partitioning, sink strength and plant development. A total of 11 SUS genes have been identified in the genome of Malus domestica (MdSUSs), and phylogenetic analysis revealed that the MdSUS genes were divided into three groups, named as SUS I, SUS II and SUS III, respectively. The SUS I and SUS III groups included four homologs each, whereas the SUS II group contained three homologs. SUS genes in the same group showed similar structural characteristics, such as exon number, size and length distribution. After assessing four different tissues, MdSUS1s and MdSUS2.1 showed the highest expression in fruit, whereas MdSUS2.2/2.3 and MdSUS3s exhibit the highest expression in shoot tips. Most MdSUSs showed decreased expression during fruit development, similar to SUS enzyme activity, but both MdSUS2.1 and MdSUS1.4 displayed opposite expression profiles. These results suggest that different MdSUS genes might play distinct roles in the sink-source sugar cycle and sugar utilization in apple sink tissues.     

银杏ERF转录因子家族的全基因组学鉴定及表达模式分析

以银杏基因组数据库为基础，通过序列比对，并经过鉴定筛选，共获得112个ERF转录因子家族成员，对其进行生物信息学及表达模式分析。结果显示：银杏112个ERF成员在系统进化树上分为10个亚家族；基因结构分析表明，大部分ERF家族基因结构简单，仅少量基因含有1～4个内含子；基因表达分析显示，39个ERF基因在雄蕊中表达量较高，20个基因在幼苗中表达量较高，40个基因在胚中表达量较高；部分基因在雄蕊、胚和幼苗中具有相同的表达模式，说明其可能具有类似的功能。     

H3N2犬流感病毒M1蛋白的原核表达及鉴定

为制备犬流感病毒(H3N2) M1蛋白纯品,针对M1基因序列设计引物,用聚合酶链式反应(PCR)扩增目的基因片段,扩增产物克隆至表达载体pET-SUMO中并转化至宿主菌BL21(DE3),诱导表达目的蛋白,探索纯化工艺,制备目的蛋白,并用Western blot检测纯化的M1目的蛋白。通过PCR成功扩增出大小为771 bp的M1基因,成功构建p ET-SUMO-M1表达载体,表达的融合蛋白相对分子量为41 kD,主要以可溶形式表达,纯化后获得蛋白纯品,Western blot检测显示用M1蛋白(28 k D)免疫小鼠制备的多抗能与制备的蛋白纯品发生特异性反应,从而证明蛋白纯品为M1目的蛋白。试验制备出的M1蛋白纯品可为进一步制备通用型抗犬流感病毒抗体提供纯品抗原。