肝胆显像螯合物—氮基三乙酸单酰苯胺及其类似物的合成

本课题合成四个氮基三乙酸单酰苯胺(IDA)类及其类似物肝胆显像螯合物。(1)用家兔做了肝胆显像扫描实验,其显像效果较好。(2)～(3)为未见报道的化合物。     

大鼠肝癌中α_2-巨球蛋白等几种分泌性蛋白基因表达的变化

用Northern blot方法对二乙基亚硝胺所诱发的大鼠肝癌中内源性蛋白酶抑制因子α_2-巨球蛋白(α_2-M)、非特异性免疫抑制剂α_1-酸性糖蛋白(α_1-AGP)及雄性激素正调控的α-2u球蛋白(α-2u)三种分泌性蛋白基因表达情况进行了分析。结果表明在大部分(14/16)肝癌样品中α_2-M RNA水平显著降低;而α_1-AGP RNA水平显著高于正常对照水平;α-2u RNA水平明显下降,但在某些雄性大鼠肝癌样品中该基因却有一定程度的表达。这些结果说明,一些肿瘤宿主血浆中α_2-M水平的显著下降及α_1-AGP水平的明显升高分别是由于基因表达活性的下降及升高所致。α-2u基因表达的异常提示,在癌变过程中机体的内分泌功能发生了某些变化。     

中蜂处女王性成熟日龄及其交尾习性的探讨

本研究对210只人工培育的出房后1,2,3,4,6,8．10日龄的中蜂处女王受精囊液的pH值进行测定．结果表明,1日龄处女王受精囊液的pH值平均为7．7,2日龄为8．5,从3日龄开始达到最高值8.8．并保持稳定状态,由此判断出房后3日龄的中蜂处女王性已成熟．通过对72只中蜂处女王交尾飞行的观察,结果表明,蜂王交尾日龄多为6-8日．最早为4日龄,最迟为16日龄;处女王认巢飞行持续时间平均为7．4分钟,交尾飞行平均为21．5分钟：处女王连续交尾飞行1-3次,有9只处女王在一天里进行2次交尾飞行．     

Proteomics and Phosphoproteomic Analysis to Identify Spleen of Takifugu rubripes Infected Cryptocaryon irritans

Marine Biotechnology - Takifugu rubripes is important commercially fish species in China and it is under serious threat from white spot disease (cyptocaryoniasis), which leads to heavy economic...     

The northern corn leaf blight resistance gene Ht1 encodes an nucleotide-binding,leucine-rich repeat immune receptor

Northern corn leaf blight, caused by the fungal pathogen Exserohilum turcicum, is a major disease of maize. The first major locus conferring resistance to E. turcicum race 0, Ht1, was identified over 50 years ago, but the underlying gene has remained unknown. We employed a map-based cloning strategy to identify the Ht1 causal gene, which was found to be a coiled-coil nucleotide-binding, leucine-rich repeat (NLR) gene, which we named PH4GP-Ht1. Transgenic testing confirmed that introducing the native PH4GP-Ht1 sequence to a susceptible maize variety resulted in resistance to E. turcicum race 0. A survey of the maize nested association mapping genomes revealed that susceptible Ht1 alleles had very low to no expression of the gene. Overexpression of the susceptible B73 allele, however, did not result in resistant plants, indicating that sequence variations may underlie the difference between resistant and susceptible phenotypes. Modelling of the PH4GP-Ht1 protein indicated that it has structural homology to the Arabidopsis NLR resistance gene ZAR1, and probably forms a similar homopentamer structure following activation. RNA sequencing data from an infection time course revealed that 1 week after inoculation there was a threefold reduction in fungal biomass in the PH4GP-Ht1 transgenic plants compared to wild-type plants. Furthermore, PH4GP-Ht1 transgenics had significantly more inoculation-responsive differentially expressed genes than wild-type plants, with enrichment seen in genes associated with both defence and photosynthesis. These results demonstrate that the NLR PH4GP-Ht1 is the causal gene underlying Ht1, which represents a different mode of action compared to the previously reported wall-associated kinase northern corn leaf blight resistance gene Htn1/Ht2/Ht3.     

TaTPP-7A positively feedback regulates grain filling and wheat grain yield through T6P-SnRK1 signalling pathway and sugar–ABA interaction

Grain size and filling are two key determinants of grain thousand-kernel weight (TKW) and crop yield, therefore they have undergone strong selection since cereal was domesticated. Genetic dissection of the two traits will improve yield potential in crops. A quantitative trait locus significantly associated with wheat grain TKW was detected on chromosome 7AS flanked by a simple sequence repeat marker of Wmc17 in Chinese wheat 262 mini-core collection by genome-wide association study. Combined with the bulked segregant RNA-sequencing (BSR-seq) analysis of an F₂ genetic segregation population with extremely different TKW traits, a candidate trehalose-6-phosphate phosphatase gene located at 135.0 Mb (CS V1.0), designated as TaTPP-7A, was identified. This gene was specifically expressed in developing grains and strongly influenced grain filling and size. Overexpression (OE) of TaTPP-7A in wheat enhanced grain TKW and wheat yield greatly. Detailed analysis revealed that OE of TaTPP-7A significantly increased the expression levels of starch synthesis- and senescence-related genes involved in abscisic acid (ABA) and ethylene pathways. Moreover, most of the sucrose metabolism and starch regulation-related genes were potentially regulated by SnRK1. In addition, TaTPP-7A is a crucial domestication- and breeding-targeted gene and it feedback regulates sucrose lysis, flux, and utilization in the grain endosperm mainly through the T6P-SnRK1 pathway and sugar–ABA interaction. Thus, we confirmed the T6P signalling pathway as the central regulatory system for sucrose allocation and source–sink interactions in wheat grains and propose that the trehalose pathway components have great potential to increase yields in cereal crops.     

Identification of tyrosines 154 and 307 in the extracellular domain and 653 and 766 in the intracellular domain as phosphorylation sites in the heparin-binding fibroblast growth factor receptor tyrosine kinase (flg).

Four tyrosine residues have been identified as phosphorylation sites in the tyrosine kinase isoform of the heparin-binding fibroblast growth factor receptor flg (FGF-R1). Baculoviral-insect cell-derived recombinant FGF-R1 was phosphorylated and fragmented with trypsin while immobilized on heparin-agarose beads. Phosphotyrosine peptides were purified by chromatography on immobilized anti-phosphotyrosine antibody and analyzed by Edman degradation and electrospray tandem mass spectrometry. Tyrosine residue 653, which is in a homologous spatial position to major autophosphorylation sites in the catalytic domain of the src and insulin receptor kinases, is the major intracellular FGF-R1 phosphorylation site. Residue 766 in the COOH-terminus outside the kinase domain is a secondary site. Tyrosine residues 154 and 307, which are in the extracellular domain of transmembrane receptor isoforms and are in an unusual sequence context for tyrosine phosphorylation, were also phosphorylated.     

Nonparametric and semiparametric estimation with sequentially truncated survival data

In observational cohort studies with complex sampling schemes, truncation arises when the time to event of interest is observed only when it falls below or exceeds another random time, that is, the truncation time. In more complex settings, observation may require a particular ordering of event times; we refer to this as sequential truncation. Estimators of the event time distribution have been developed for simple left-truncated or right-truncated data. However, these estimators may be inconsistent under sequential truncation. We propose nonparametric and semiparametric maximum likelihood estimators for the distribution of the event time of interest in the presence of sequential truncation, under two truncation models. We show the equivalence of an inverse probability weighted estimator and a product limit estimator under one of these models. We study the large sample properties of the proposed estimators and derive their asymptotic variance estimators. We evaluate the proposed methods through simulation studies and apply the methods to an Alzheimer's disease study. We have developed an R package, seqTrun , for implementation of our method.     

Effects of ROS and caspase-3-like protein on the growth and aerenchyma formation of Potamogeton perfoliatus stem

Protoplasma - Aerenchyma formation plays an important role in the survival of Potamogeton perfoliatus in submerged environment. To understand the regulatory role of reactive oxygen species (ROS)...     

The Effect of High-Temperature Stress on the Physiological Indexes,Chloroplast Ultrastructure,and Photosystems of two Herbaceous Peony Cultivars

In this study, two herbaceous peony cultivars with different heat tolerances (‘Fenyunu’ FYN low sensitivity and ‘Qiaoling’ QL high sensitivity) were used as research materials. An integrated view of the factors underlying the decrease in photosynthetic rate under high-temperature (HT) stress was provided by analyzing the biochemical parameters, chloroplast ultrastructure, gas-exchange parameters, chlorophyll fluorescence, and modulated 820 nm reflection of herbaceous peony leaves. The results showed that hydrogen peroxide, superoxide anion, malondialdehyde, and electrical conductivity increased significantly, while the photosynthetic pigments content and photosynthetic capacity decreased significantly in QL than in FYN under HT. The contents of soluble sugars and proline increased greatly in FYN than in QL, while the activity of SOD decreased markedly in QL than in FYN after HT. Compared with FYN, the ultrastructure of QL was more seriously disrupted under HT. Chlorophyll fluorescence analysis showed that HT changed the shapes of OJIP curve, resulting in the increase of K phase and J phase. The PSII acceptor side was more damaged than the donor side, and the electron transfer was seriously blocked. The energy flow in the process of light energy absorption, capture, and electron transfer were significantly changed after HT stress. Meanwhile, PSI was also significantly inhibited, and the coordination of both photosystems decreased. The variation of these parameters in FYN was less than that in QL. These results suggested that FYN featured a more heat-tolerance ability as evidenced by the good performances on the antioxidant system, osmoregulatory capacity, and the thermostability of membranes and photosystems.