Characterization and molecular cloning of dabocetin, a potent antiplatelet C-type lectin-like protein from Daboia russellii siamensis venom

A novel C-type lectin-like protein, dabocetin, was purified from Daboia russellii siamensis venom. On SDS-polyacrylamide gel electrophoresis, it showed a single band with an apparent molecular weight of 28 kDa and two distinct bands with the apparent mole

Purification, characterization and cloning of two novel tigerinin-like peptides from skin secretions of Fejervarya cancrivora

While investigating the innate defense of brackish water-living amphibian and its comparison with freshwater-living amphibians, two novel 12-residue antimicrobial peptides were purified from the skin secretions of the crab-eating frog, Fejervarya cancrivo

Enriched environment treatment counteracts enhanced addictive and depressive-like behavior induced by prenatal chronic stress

Prenatal stress can cause many long-term behavior changes in offspring, but whether prenatal stress can alter addictive behavior in offspring and postnatal enriched environment treatment (EE) can restore these changes are unknown. We reported here that pr

A horsefly saliva antigen 5-like protein containing RTS motif is an angiogenesis inhibitor

The Ag5 proteins are the most abundant and immunogenic proteins in the venom secretory ducts of stinging insects. An antigen 5-like protein (named tabRTS) composed of 221 amino acid residues was purified and characterized from the salivary glands of the horsefly, Tabanus yao (Diptera, Tabanidae). Its cDNA was cloned from the cDNA library of the horsefly's salivary gland. TabRTS containing the SCP domain (Sc7 family of extracellular protein domain) was found in insect antigen 5 proteins. More interestingly, there is an Arg-Thr-Ser (RTS) disintegrin motif at the C-terminus of tabRTS. The RTS motif is positioned in a loop bracketed by cysteine residues as those found in RTS-disintegrins of Crotalidae and Viperidae snake venoms, which act as angiogenesis inhibitors. Endothelial Cell Tube formation assay in vitro and chicken chorioallantoic membrane (CAM) angiogenesis assay in vivo were performed as to investigate the effect of tabRTS on angiogenesis. It was found that tabRTS could significantly inhibit angiogenesis in vitro and in vivo. Anti-alpha(1)beta(1) monoclonal antibody could dose-dependently inhibit the anti-angiogenic activity of tabRTS. This result indicated that tabRTS possibly targets the alpha(1)beta(1) integrin to exert the anti-angiogenic activity as snake venom RTS-/KTS-disintegrins do. The current work revealed the first angiogenesis inhibitor protein containing RTS motif from invertebrates, a possible novel type of RTS-disintegrin. (C) 2009 Elsevier Ltd. All rights reserved.

A Plant Needs Ants like a Dog Needs Fleas: Myrmelachista schumanni Ants Gall Many Tree Species to Create Housing

Hundreds of tropical plant species house ant colonies in specialized chambers called domatia. When, in 1873, Richard Spruce likened plant-ants to fleas and asserted that domatia are ant-created galls, he incited a debate that lasted almost a century. Alth

Characterization of a thrombin-like enzyme from the venom of Trimeresurus jerdonii

From the venom of Trimeresurus jerdonii, a distinct thrombin-like enzyme, called jerdonobin. was purified by DEAF A-25 ion-exchange chromatography, Sephadex G-75 gel filtration, and fast protein liquid chromatography (FPLC). SDS-PAGE analysis of this enzyme shows that it consists of a single polypeptide chain with a molecular weight of 38,000. The NH2-terminal amino acid sequence of jerdonobin has great homology with venom thrombin-like enzymes documented. Jerdonobin is able to hydrolyze several chromogenic substrates. The enzyme directly clots fibrinogen with an activity of 217 NIH units/mg, The fibrinopeptides released, identified by HPLC consisted of fibrinopeptide A and a small amount of fibrinopepide B. The activities of the enzyme were inhibited by phenylmethylsulfonyl fluoride (PMSF) and p-nitrophenyl-p-guanidinobenzoate (NPGB). However, metal chelator (EDTA) had no effect on it. indicating it is venom serine protease. (C) 2000 Elsevier Science Ltd. All rights reserved.

Purification and cloning of a novel C-type lectin-like protein with platelet aggregation activity from Trimeresurus mucrosquamatus venom

TMVA, a novel C-type lectin-like protein that induces platelet aggregation in a dose-dependent manner, was purified from the venom of Trimeresurus mucrosquamatus. It consists of two subunits, alpha (15,536 Da) and beta (14,873 Da). The mature amino acid sequences of the a (135 amino acids) and beta subunits (123 amino acids) were deduced from cloned cDNAs. Both of the sequences show great similarity to C-type lectin-like venom proteins, including a carbohydrate recognition domain. The cysteine residues of TMVA are conserved at positions corresponding to those of flavocetin-A and convulxin, including the additional Cys135 in the alpha subunit and Cys3 in the beta subunit. SDS-PAGE, mass spectrometry analysis and amino acid sequence showed that native TMVA exists as two convertible multimers Of (alphabeta)(2) and (alphabeta)(4) with molecular weights of 63,680 and 128,518 Da, respectively. The (alphabeta)(2) complex is stabilized by an interchain disulfide bridge between the two alphabeta-heterodimers, whereas the stabilization of the (alphabeta)(4) complex seems to involve non-covalent interactions between the (alphabeta)(2) complexes. (C) 2002 Elsevier Science Ltd. All rights reserved.

Identification of Sarcocystis hominis-like (Protozoa : Sarcocystidae) cyst in water buffalo (Bubalus bubalis) based on 18S rRNA gene sequences

DNA templates were extracted from isolates of Sarcocystis hominis-like cysts collected from cattle and water buffalo, as well as from Sarcocystis fusiformis cysts and Sarcocystis suihominis cysts. The 18S rRNA genes were amplified using DNA from a single

Absence of association between SNPs in the promoter region of the insulin-like growth factor 1 (IGF-1) gene and longevity in the Han Chinese population

Previous studies have indicated that genetic variations in the factors of insulin/insulin-like growth factor 1 (IGF-1) signaling pathway could influence human life-span by affecting IGF-1 levels. The promoter region of the IGF-1 gene is an obvious candida

A Profound Role for the Expansion of Trypsin-Like Serine Protease Family in the Evolution of Hematophagy in Mosquito

The trypsin-like serine protease (Tryp_SPc) family is ubiquitous in animals and plays diverse roles, especially in the digestive system, in different phyla. In the mosquito, some Tryp_SPc proteases make important contributions to the digestion of the bloo

A molecular model of braid-like DNA structure

The three-dimensional molecular models of DNA triple helices and triple-stranded brain-like structure were built up by molecular architecture, and their structural features and energy decomposition were examined. The results showed: (i) The base triplet is the element forming braid-like and triple helix DNA; (ii) Under specified conditions, DNA could form the triplet-stranded braid-like structure; (iii) DNA stability of the braid-like structure is less than that of the triple helix structure. (C) 1995 Academic Press Limited.

Enriched environment experience overcomes the memory deficits and depressive-like behavior induced by early life stress

Stress in early life is believed to cause cognitive and affective disorders, and to disrupt hippocampal synaptic plasticity in adolescence into adult, but it is unclear whether exposure to enriched environment (EE) can overcome these effects. Here, we rep

Theoretical studies on conformation comparison of braid-like and triplex DNA

Based on the experimental data of scanning tunneling microscopy (STM), models of three-stranded braid-like DNAs composed by three kinds of base triplets AAA, TAT and GCA were constructed. We investigated the braid-like DNAs and their comparative tripler DNAs using a molecular mechanics method. The three strands of braid-like DNAs are proven equivalent, while those of tripler DNAs are not. The conformational energies for braid-like DNAs were found to be higher than that for tripler DNAs. Each period in one strand of braid-like DNA has 18 nucleotides, half of which are right-handed, while the other half are left-handed. Additional discussions concerning sugar puckering modes and the H-bonds are also included. (C) 1999 Elsevier Science B.V. All rights reserved.

鲫鱼蛋白激酶PKR-like的Zα结构域与聚肌胞苷酸的结合

根据鲫鱼类PKR蛋白激酶基因(CaPKR-like)的全长cDNA序列,克隆CaPKR-likeZα结构域cDNA(Zα1、Zα2和Zα1Zα2),原核表达成功获得3种融合蛋白PZα1、PZα2和PZα1Zα2。凝胶阻滞实验结果显示:PZα1、PZα2、PZα1和PZα2混合表达蛋白不能与聚肌胞苷酸(PolyI∶C)结合,而表达完整的Zα结构域的PZα1Zα2与PolyI∶C有明显的结合现象。另外,3种表达多肽PZα1、PZα2和PZα1Zα2在体外分别都能聚合形成二聚体。与PZα1相比,PZα2和PZα

DnaJ-like protein gene sll1384 is involved in phototaxis in Synechocystis sp PCC 6803

In Synechocystis sp. PCC 6803, gene sll1384 encodes a protein with a DnaJ domain at its N-terminal portion and a TPR domain at the C-terminal portion. An sll1384 mutant shows no difference from the wild type in adaptation to different temperatures, but almost completely loses its capability of phototactic movement. After complementation with sll1384, the mutant regains the phototaxis. As shown with electron microscopy, on the cell surface, mutant cells have pili that appear to be the same as that of the wild type. Also, the transformation efficiency remains unchanged in the mutant. It is postulated that Sll1384 regulates phototaxis of Synechocystis through protein-protein interaction. It is the first DnaJ-like protein gene identified in a cyanobacterium for a role in phototaxis.