Phylogeny, diversity, and species delimitation in some species of the Xiphinema americanum-group complex (Nematoda: Longidoridae), as inferred from nuclear and mitochondrial DNA sequences and morphology

During nematode surveys in southern Spain and Italy 14 populations of Xiphinema species tentatively identified as Xiphinema americanum-group were detected. Morphological and morphometrical studies identified three new species and six known Xiphinema americanum-group species, viz.: Xiphinema parabrevicolle n. sp., Xiphinema parapachydermum n. sp., Xiphinema paratenuicutis n. sp., Xiphinema duriense, Xiphinema incertum, Xiphinema opisthohysterum, Xiphinema pachtaicum, Xiphinema rivesi, and Xiphinema santos. The Xiphinema americanum-group is the most difficult Xiphinema species group for diagnosis since the morphology is very conservative and morphometric characters often overlap. This group includes vectors of several important plant pathogenic viruses that cause significant damage to a wide range of agricultural crops. Molecular characterisation of these species using D2-D3 expansion regions of 28S rRNA, 18S rRNA, ITS1-rRNA and the protein-coding mitochondrial gene, cytochrome oxidase c subunit 1 was carried out and maximum likelihood and Bayesian inference analysis were used to reconstruct phylogenetic relationships among these species and with other Xiphinema americanum-group species.     

油菜素内酯代谢相关基因BAS1等位变异影响小麦籽粒密度及粒重表型

BAS1(phy B activation-tagged suppressor1)是调控油菜素内酯活性的关键基因。本研究利用由和尚麦和豫麦8679杂交后代构建的RIL群体(包括129个家系),研究了BAS1和小麦千粒重、籽粒密度两个产量性状的关系。结果表明BAS1基因位点等位变异对千粒重和籽粒密度具有显著的影响,B型等位基因的家系其千粒重和籽粒密度均值均显著高于A型等位基因的家系。相关分析表明,BAS1位点等位变异分别与千粒重和籽粒密度呈显著(0.178*)和极显著(0.327***)正相关。研究结果揭示了BAS1基因位点等位变异与小麦粒重、籽粒密度间的密切联系,这对解释小麦产量形成机制及其指导高产育种具有重要的意义。     

大豆中GmRAD与GmDIV基因的in silico鉴定及表达分析

RAD与DIV属于MYB转录因子家族成员,在金鱼草研究中发现它们对花对称性的形成起着重要作用。本研究利用全基因组信息鉴定了大豆中的GmRAD与GmDIV基因,分析了其蛋白的理化性质、二级结构,基因结构与其在染色体上的分布,并对其系统发生和表达方式进行了研究。研究表明:大豆中存在5个GmRAD基因和5个GmDIV基因,它们分别属于MYB家族的R1和R2R3类,分布在大豆的9条染色体上;进化分析显示GmRAD和GmDIV基因具有不同的进化历程,GmDIV比GmRAD基因更趋于单元发生;表达分析证明,GmDIV和GmRAD成员具有不同的表达模式,其中GmRAD3和GmRAD5以及GmDIV1、GmDIV3、GmDIV4和GmDIV5在花组织中有较高的表达。     

盐胁迫下棉花叶片差异蛋白表达的分析

以耐盐的陆地棉品种中07为研究材料,在其生长的三叶期,用未处理和0.4%NaCl胁迫处理24h的幼苗,分别提取其叶片全蛋白。通过等电聚焦和第二向SDS-PAGE技术获得完整的棉花叶片总蛋白图,利用ImageMaste-2DElite5.0软件分析各个差异蛋白在对照和0.4%NaCl胁迫24h后棉花叶片中的相对表达量,并选取质量好、实验重复性高的10个特异的差异表达蛋白质点进行基质辅助激光解吸电离串联飞行时间质谱(MALDI-TOF-TOF/MS)鉴定。结果表明,从对照和盐胁迫处理的双向电泳图谱中共检测到24个差异蛋白质点,这些差异蛋白质点的等电点分布集中在5.0～6.5之间,分子量分布集中在40.0～110.0kD之间;进一步质谱(MALDI-TOF-TOF/MS)分析鉴定的10个差异蛋白质点,其中4个蛋白质点获得了鉴定结果,这4个差异表达蛋白质点分别为1,5-二磷酸核酮糖羧化/氧化激酶α2(编号4)、1,5-二磷酸核酮糖羧化酶/氧化酶大亚基(编号5)、未知蛋白产物(编号19)和OEE2(编号32)。我们初步推测OEE2和1,5-二磷酸核酮糖羧化酶/氧化酶可能与棉花耐盐胁迫特性有关。     

毛白杨植物络合素合酶(PtPCS)基因克隆及其表达研究

植物络合素(PCs)是植物细胞中一类螯合重金属离子的多肽,对细胞解毒和重金属的富集有重要的作用。植物络合素合酶(PCS)是合成PCs途径中的关键酶。本研究克隆了毛白杨的植物络合素合酶基因PtPCS,该基因cDNA序列全长1512bp,可编码503个氨基酸;与其它8种植物同源基因比对显示,它们的氨基酸序列相似性在67%～74.1%之间;构建进化树发现,这9种植物明显的分为两大分支,并且两大分支PCS蛋白的高级结构显示出明显的差异,一种呈月牙状,一种为伞状,重金属超富集植物均为月牙状结构。对毛白杨在不同镉浓度处理下PtPCS基因的表达情况分析发现,毛白杨根、茎、叶中PtPCS基因均表现出先升高后缓慢降低的表达趋势,并且在同一镉浓度处理下,毛白杨不同器官PtPCS基因的表达具有规律性,即根表达量最强,茎次之,叶片最弱。研究结果不仅为植物育种提供了重要的基因资源,也为剖析毛白杨的镉抗性和富集特性的研究奠定了良好的基础。     

First genetic characterization of equine adenovirus type 1 (EAdV-1) in Turkey

Equine adenovirus type 1 (EAdV-1) is a cause of repiratory tract infection in equids. In present study for the first time in Turkey, the prevalence of EAdV-1 in nasal swab samples obtained from horses showing respiratory symptoms was investigated by polymerase chain reaction (PCR), and molecular characterization of the hexon gene detected in the Turkish (TR) strain was performed. Overall, the prevalence of EAdV-1 was found low (1.4%) as indicated by a positive PCR reaction from the nasal swab extracts tested. Phylogenetic analysis based on the partial sequences of the hexon gene of a TR-EAdV-1 strain with those of previously isolated AdVs from different mammals and an EAdV-1 M1 strain showed that the EAdV-1 strains were placed into a unique cluster. Although the TR-EAdV-1 strain was closely related to CAV-1, CAV-2 and bat adenovirus reference strains, larger-scale studies are necessary to better understand the molecular epidemiology and population structure of EAdV-1 in Turkey.     

Gastroprotective potential of frutalin, a D-galactose binding lectin, against ethanol-induced gastric lesions

The present study was designed to verify whether frutalin (FTL) affords gastroprotection against the ethanol-induced gastric damage and to examine the underlying mechanism(s). Gastric damage was induced by intragastric administration of 0.2 ml of ethanol (96%). Mice in groups were pretreated with FTL (0.25, 0.5 and 1 mg/kg; i.p.), cimetidine (100 mg/kg; p.o.), or vehicle (0.9% of NaCl, 10 mL/kg; p.o.), 30 min before ethanol administration. They were sacrificed 30 min later, the stomachs excised, and the mucosal lesion area (mm2) measured by planimetry. Gastroprotection was assessed in relation to inhibition of gastric lesion area. To study the gastroprotective mechanism(s), its relations to capsaicin-sensitive fibers, endogenous prostaglandins, nitric oxide, sulphydryls, ATP-sensitive potassium channels, adrenoceptors, opioid receptors and calcium channels were analyzed. Treatments effects on ethanol-associated oxidative stress markers GSH and MDA were measured in gastric tissue. FTL afforded a dose-unrelated gastroprotection against the ethanol damage. However, it failed to prevent the ethanol-induced changes in the levels of GSH and MDA. It was observed that the gastroprotection by FTL was greatly reduced in animals pretreated with capsazepine, indomethacin, L-NAME or glibenclamide. Considering the results, it is suggested that the FTL could probably be a good therapeutic agent for the development of new medicine for the treatment of gastric ulcer.