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111.
Xiao  Na  Zhang  Jun  Chen  Chao  Wan  Yanfang  Wang  Ning  Yang  Jing 《Mammalian genome》2019,30(9-10):276-288
Mammalian Genome - Increasing evidence shows that miRNAs play pivotal roles in cardiovascular diseases, including heart failure (HF). The aim of this study was to investigate the role of miR-129-5p...  相似文献   
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Journal of Industrial Microbiology & Biotechnology - Although CRISPR/Cas9-mediated gene editing technology has developed vastly in Escherichia coli, the chromosomal integration of large DNA...  相似文献   
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Growth in the pharmaceutical industry has led to an increasing demand for rapid characterization of therapeutic monoclonal antibodies. The current methods for antibody sequence confirmation (e.g., N-terminal Edman sequencing and traditional peptide mapping methods) are not sufficient; thus, we developed a fast method for sequencing recombinant monoclonal antibodies using a novel digestion-on-emitter technology. Using this method, a monoclonal antibody can be denatured, reduced, digested, and sequenced in less than an hour. High throughput and satisfactory protein sequence coverage were achieved by using a non-specific protease from Aspergillus saitoi, protease XIII, to digest the denatured and reduced monoclonal antibody on an electrospray emitter, while electrospray high voltage was applied to the digestion mixture through the emitter. Tandem mass spectrometry data was acquired over the course of enzyme digestion, generating similar information compared to standard peptide mapping experiments in much less time. We demonstrated that this fast protein sequencing method provided sufficient sequence information for bovine serum albumin and two commercially available monoclonal antibodies, mouse IgG1 MOPC21 and humanized IgG1 NISTmAb. For two monoclonal antibodies, we obtained sequence coverage of 90.5–95.1% for the heavy chains and 98.6–99.1% for the light chains. We found that on-emitter digestion by protease XIII generated peptides of various lengths during the digestion process, which was critical for achieving sufficient sequence coverage. Moreover, we discovered that the enzyme-to-substrate ratio was an important parameter that affects protein sequence coverage. Due to its highly automatable and efficient design, our method offers a major advantage over N-terminal Edman sequencing and traditional peptide mapping methods in the identification of protein sequence, and is capable of meeting an ever-increasing demand for monoclonal antibody sequence confirmation in the biopharmaceutical industry.  相似文献   
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Previous studies have demonstrated roles for vesicle-associated membrane protein 2 (VAMP 2) and VAMP 8 in Ca(2+)-regulated pancreatic acinar cell secretion, however, their coordinated function in the secretory pathway has not been addressed. Here we provide evidence using immunofluorescence microscopy, cell fractionation, and SNARE protein interaction studies that acinar cells contain two distinct populations of zymogen granules (ZGs) expressing either VAMP 2 or VAMP 8. Further, VAMP 8-positive granules also contain the synaptosome-associated protein 29, whereas VAMP 2-expressing granules do not. Analysis of acinar secretion by Texas red-dextran labeling indicated that VAMP 2-positive ZGs mediate the majority of exocytotic events during constitutive secretion and also participate in Ca(2+)-regulated exocytosis, whereas VAMP 8-positive ZGs are more largely involved in Ca(2+)-stimulated secretion. Previously undefined functional roles for VAMP and syntaxin isoforms in acinar secretion were established by introducing truncated constructs of these proteins into permeabilized acini. VAMP 2 and VAMP 8 constructs each attenuated Ca(2+)-stimulated exocytosis by 50%, whereas the neuronal VAMP 1 had no effects. In comparison, the plasma membrane SNAREs syntaxin 2 and syntaxin 4 each inhibited basal exocytosis, but only syntaxin 4 significantly inhibited Ca(2+)-stimulated secretion. Syntaxin 3, which is expressed on ZGs, had no effects. Collectively, these data demonstrate that individual acinar cells express VAMP 2- and VAMP 8-specific populations of ZGs that orchestrate the constitutive and Ca(2+)-regulated secretory pathways.  相似文献   
117.

Background

Attempts over the last three decades to reconstruct the phylogenetic history of the Anopheles gambiae species complex have been important for developing better strategies to control malaria transmission.

Methodology

We used fingerprint genotyping data from 414 field-collected female mosquitoes at 42 microsatellite loci to infer the evolutionary relationships of four species in the A. gambiae complex, the two major malaria vectors A. gambiae sensu stricto (A. gambiae s.s.) and A. arabiensis, as well as two minor vectors, A. merus and A. melas.

Principal Findings

We identify six taxonomic units, including a clear separation of West and East Africa A. gambiae s.s. S molecular forms. We show that the phylogenetic relationships vary widely between different genomic regions, thus demonstrating the mosaic nature of the genome of these species. The two major malaria vectors are closely related and closer to A. merus than to A. melas at the genome-wide level, which is also true if only autosomes are considered. However, within the Xag inversion region of the X chromosome, the M and two S molecular forms are most similar to A. merus. Near the X centromere, outside the Xag region, the two S forms are highly dissimilar to the other taxa. Furthermore, our data suggest that the centromeric region of chromosome 3 is a strong discriminator between the major and minor malaria vectors.

Conclusions

Although further studies are needed to elucidate the basis of the phylogenetic variation among the different regions of the genome, the preponderance of sympatric admixtures among taxa strongly favor introgression of different genomic regions between species, rather than lineage sorting of ancestral polymorphism, as a possible mechanism.  相似文献   
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Fishmeal wastewater, a seafood processing waste, was utilized for production of lactic acid and fungal biomass by Rhizopus oryzae AS 3.254 with the addition of sugars. The 30 g/l exogenous glucose in fishmeal wastewater was superior to starch in view of productivities of lactic acid and fungal biomass, and COD reduction. Fishmeal wastewater can be a replacement for peptone which was the most suitable nitrogen source for lactic acid production among the tested organic or inorganic nitrogen sources. Exogenous NaCl (12 g/l) completely inhibited the production of lactic acid and fungal growth. In the medium of COD 5,000 mg/l fishmeal wastewater with the addition of 30 g/l glucose, the maximum productivity of lactic acid was 0.723 g/l h corresponding to productivity of fungal biomass 0.0925 g/l h, COD reduction 84.9% and total nitrogen removal 50.3% at a fermentation time of 30 h.  相似文献   
120.
Li  Nan  Shi  Hangyu  Hou  Pengfei  Gao  Lu  Shi  Yongqiang  Mi  Weiyang  Zhang  Gang  Wang  Ning  Dai  Wei  Wei  Lin  Jin  Tianbo  Shi  Yongzhi  Guo  Shiwen 《Functional & integrative genomics》2022,22(1):27-33
Functional & Integrative Genomics - This study ascertained to explore the potential contribution of ARRDC3 polymorphisms in the risk and prognosis of glioma. One thousand sixty-one patients and...  相似文献   
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