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Wang Y.,Zhejiang Academy of Medical science | Ma A.,Zhejiang Academy of Medical science | Chen S.-B.,National Institute of Parasitic Diseases | Yang Y.-C.,Institute for Biological Product Control | And 2 more authors.
Infection, Genetics and Evolution | Year: 2014

Pv12, Pv38 and Pv41, the three 6-Cys family proteins which are expressed in the blood-stage of vivax malaria, might be involved in merozoite invasion activity and thus be potential vaccine candidate antigens of Plasmodium vivax. However, little information is available concerning the genetic diversity and natural selection of these three proteins. In the present study, we analyzed the amino acid sequences of P. vivax blood-stage 6-Cys family proteins in comparison with the homologue proteins of Plasmodium cynomolgi strain B using bioinformatic methods. We also investigated genetic polymorphisms and natural selection of these three genes in P. vivax populations from the China-Myanmar endemic border. The three P. vivax blood-stage 6-Cys proteins were shown to possess a signal peptide at the N-terminus, containing two s48/45 domains, and Pv12 and Pv38 have a GPI-anchor motif at the C-terminus. Then, 22, 21 and 29 haplotypes of pv12, pv38 and pv41 were identified out of 45, 38 and 40 isolates, respectively. The dN/dS values for Domain II of pv38 and pv41 were 3.33880 and 5.99829, respectively, suggesting positive balancing selection for these regions. Meanwhile, the C-terminus of pv41 showed high nucleotide diversity, and Tajima's D test suggested that this fragment could be under positive balancing selection. Overall, our results have significant implications, providing a genetic basis for blood-stage malaria vaccine development based on these three 6-Cys proteins. © 2014 Elsevier B.V.

Ruan Z.,Huazhong Agricultural University | Ruan Z.,Chinese Academy of Agricultural Sciences | Zhai Y.,Chongqing Academy of Agricultural science | Song J.,Chinese Academy of Agricultural Sciences | And 4 more authors.
PLoS ONE | Year: 2013

A novel pyrethroid-degrading esterase gene pytY was isolated from the genomic library of Ochrobactrum anthropi YZ-1. It possesses an open reading frame (ORF) of 897 bp. Blast search showed that its deduced amino acid sequence shares moderate identities (30% to 46%) with most homologous esterases. Phylogenetic analysis revealed that PytY is a member of the esterase VI family. pytY showed very low sequence similarity compared with reported pyrethroid-degrading genes. PytY was expressed, purified, and characterized. Enzyme assay revealed that PytY is a broad-spectrum degrading enzyme that can degrade various pyrethroids. It is a new pyrethroid-degrading gene and enriches genetic resource. Kinetic constants of Km and Vmax were 2.34 mmol·L-1 and 56.33 nmol min-1, respectively, with lambda-cyhalothrin as substrate. PytY displayed good degrading ability and stability over a broad range of temperature and pH. The optimal temperature and pH were of 35°C and 7.5. No cofactors were required for enzyme activity. The results highlighted the potential use of PytY in the elimination of pyrethroid residuals from contaminated environments. © 2013 Ruan et al.

Chen X.,Tsinghua University | Quan Y.,Tsinghua University | Quan Y.,Institute for Biological Product Control | Wang H.,Tsinghua University | Luo H.,Tsinghua University
PLoS ONE | Year: 2014

As one of the major hydrolases in Drosophila, trehalase (Treh) catalyzes the hydrolysis of trehalose into glucose providing energy for flight muscle activity. Treh is highly conserved from bacteria to humans, but little is known about its function during animal development. Here, we analyze the function of Treh in Drosophila optic lobe development. In the optic lobe, neuroepithelial cells (NEs) first divide symmetrically to expand the stem cell pool and then differentiate into neuroblasts, which divide asymmetrically to generate medulla neurons. We find that the knockdown of Treh leads to a loss of the lamina and a smaller medulla. Analyses of Treh RNAi-expressing clones and loss-of-function mutants indicate that the lamina and medulla phenotypes result from neuroepithelial disintegration and premature differentiation into medulla neuroblasts. Although the principal role of Treh is to generate glucose, the Treh loss-of-function phenotype cannot be rescued by exogenous glucose. Thus, our results indicate that in addition to being a hydrolase, Treh plays a role in neuroepithelial stem cell maintenance and differentiation during Drosophila optic lobe development. © 2014 Chen et al.

Yuan B.-Z.,Institute for Biological Product Control
Chinese Journal of Biologicals | Year: 2013

A fast growth has recently been achieved in development of stem cell-based medicinal products (SCMPs), which are undergoing tests in a variety of clinical trials for treating different diseases, such as degenerative diseases, ischemic cardiovascular diseases, liver cirrhosis and diabetes. However, as an emerging promising biotherapeutical product, the SCMP-related risks do exist and can cause failure or even severe adverse responses in the SCMP-based therapies. To help develop a general guideline to ensure the quality of SCMPs for both safety and efficacy in treatments, we summarize some recent achievements in understanding both the intrinsic and extrinsic risk factors in association with types, characteristics and intended use of different SCMPs in this paper.

Na T.,Institute for Biological Product Control | Peng J.-B.,University of Alabama at Birmingham
Handbook of Experimental Pharmacology | Year: 2014

TRPV5 is one of the two channels in the TRPV family that exhibit high selectivity to Ca2+ ions. TRPV5 mediates Ca2+ influx into cells as the first step to transport Ca2+ across epithelia. The specialized distribution in the distal tubule of the kidney positions TRPV5 as a key player in Ca2+ reabsorption. The responsiveness in expression and/or activity of TRPV5 to hormones such as 1,25-dihydroxyvitamin D3, parathyroid hormone, estrogen, and testosterone makes TRPV5 suitable for its role in the fine-tuning of Ca2+ reabsorption. This role is further optimized by the modulation of TRPV5 trafficking and activity via its binding partners; co-expressed proteins; tubular factors such as calbindin- D28k, calmodulin, klotho, uromodulin, and plasmin; extracellular and intracellu- lar factors such as proton, Mg2+, Ca2+, and phosphatidylinositol-4,5- bisphosphate; and fluid flow. These regulations allow TRPV5 to adjust its overall activity in response to the body’s demand for Ca2+ and to prevent kidney stone formation. A point mutation in mouse Trpv5 gene leads to hypercalciuria similar to Trpv5 knockout mice, suggesting a possible role of TRPV5 in hypercalciuric disorders in humans. In addition, the single nucleotide polymorphisms in Trpv5 gene prevalently present in African descents may contribute to the efficient renal Ca2+ reabsorption among African descendants. TRPV5 represents a potential therapeutic target for disorders with altered Ca2+ homeostasis. © Springer-Verlag Berlin Heidelberg 2014.

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