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21.
Khoo Kelvin H. P. Sheedy Jason G. Taylor Julian D. Croser Janine S. Hayes Julie E. Sutton Tim Thompson John P. Mather Diane E. 《Molecular breeding : new strategies in plant improvement》2021,41(12):1-13
Molecular Breeding - Plant height is vital for crop yield by influencing plant architecture and resistance to lodging. Although lots of quantitative trait loci (QTLs) controlling plant height had... 相似文献
22.
Whitfield Alan K. Adams Janine B. Harrison Trevor D. Lamberth Stephen J. Lemley Daniel A. MacKay Fiona Van Niekerk Lara Weyl Olaf L. F. 《Biological invasions》2021,23(9):2729-2747
Biological Invasions - We review the possible impacts of non-native biota on the indigenous fishes of South African estuaries, including macrophytes, algae, pathogens, invertebrates, and fishes.... 相似文献
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24.
S. E. Nyquist K. Acuff Charles F. Kettering 《Preparative biochemistry & biotechnology》2013,43(4):365-373
The preparation of Golgi apparatus fractions from rat testis germ cells free from contamination by residual body fragments was accomplished by the use of the Yeda press as the homogenization device. The Golgi apparatus thus prepared retained excellent stuctural intactness. This method also allows for isolation of Golgi apparatus from single cell suspensions. 相似文献
25.
Janine O. Ilagan Robert J. Chalkley A.L. Burlingame Melissa S. Jurica 《RNA (New York, N.Y.)》2013,19(3):400-412
In spliceosomes, dynamic RNA/RNA and RNA/protein interactions position the pre-mRNA substrate for the two chemical steps of splicing. Not all of these interactions have been characterized, in part because it has not been possible to arrest the complex at clearly defined states relative to chemistry. Previously, it was shown in yeast that the DEAD/H-box protein Prp22 requires an extended 3′ exon to promote mRNA release from the spliceosome following second-step chemistry. In line with that observation, we find that shortening the 3′ exon blocks cleaved lariat intron and mRNA release in human splicing extracts, which allowed us to stall human spliceosomes in a new post-catalytic complex (P complex). In comparison to C complex, which is blocked at a point following first-step chemistry, we detect specific differences in RNA substrate interactions near the splice sites. These differences include extended protection across the exon junction and changes in protein crosslinks to specific sites in the 5′ and 3′ exons. Using selective reaction monitoring (SRM) mass spectrometry, we quantitatively compared P and C complex proteins and observed enrichment of SF3b components and loss of the putative RNA-dependent ATPase DHX35. Electron microscopy revealed similar structural features for both complexes. Notably, additional density is present when complexes are chemically fixed, which reconciles our results with previously reported C complex structures. Our ability to compare human spliceosomes before and after second-step chemistry has opened a new window to rearrangements near the active site of spliceosomes, which may play roles in exon ligation and mRNA release. 相似文献
26.
Jelena Perovic Cristina Silvar Janine Koenig Nils Stein Dragan Perovic Frank Ordon 《Molecular breeding : new strategies in plant improvement》2013,32(1):61-69
Recent advances in next-generation sequencing techniques and the development of genomics resources for crop plants with large genomes allow the detection of a large number of single nucleotide polymorphisms (SNPs) and their use in a high-throughput manner. However, such large numbers of SNPs are on the one hand not needed in some plant breeding projects and on the other hand not affordable in some cases, raising the need for fast and low-cost innovative techniques for marker detection. In marker selection in plant breeding programs, cleaved amplified polymorphic sequence (CAPS) markers still play a significant role as a complement to other high-throughput methods for SNP genotyping. New methods focusing on the acceleration of CAPS-based genotyping are therefore highly desirable. The combination of the classical CAPS method and a M13-tailed primer multiplexing assay was used to develop an agarose-gel-free protocol for the analysis of SNPs via restriction enzyme digestion. PCR products were fluorescence-labeled with a universal M13 primer and subsequently digested with the appropriate restriction endonuclease. After mixing differently labeled products, they were detected in a capillary electrophoresis system. This method allowed the cost-effective genotyping of several SNPs in barley in a multiplexed manner at an overall low cost in a short period of time. This new method was efficiently combined with the simultaneous detection of simple sequence repeats in the same electrophoresis run, resulting in a procedure well suited for marker-based selection procedures, genotyping of mapping populations and the assay of genetic diversity. 相似文献
27.
Sara Rosati Ewald TJ van den Bremer Janine Schuurman Paul WHI Parren Johannis P Kamerling Albert JR Heck 《MABS-AUSTIN》2013,5(6):917-924
Here, we describe a fast, easy-to-use, and sensitive method to profile in-depth structural micro-heterogeneity, including intricate N-glycosylation profiles, of monoclonal antibodies at the native intact protein level by means of mass spectrometry using a recently introduced modified Orbitrap Exactive Plus mass spectrometer. We demonstrate the versatility of our method to probe structural micro-heterogeneity by describing the analysis of three types of molecules: (1) a non-covalently bound IgG4 hinge deleted full-antibody in equilibrium with its half-antibody, (2) IgG4 mutants exhibiting highly complex glycosylation profiles, and (3) antibody-drug conjugates. Using the modified instrument, we obtain baseline separation and accurate mass determination of all different proteoforms that may be induced, for example, by glycosylation, drug loading and partial peptide backbone-truncation. We show that our method can handle highly complex glycosylation profiles, identifying more than 20 different glycoforms per monoclonal antibody preparation and more than 30 proteoforms on a single highly purified antibody. In analyzing antibody-drug conjugates, our method also easily identifies and quantifies more than 15 structurally different proteoforms that may result from the collective differences in drug loading and glycosylation. The method presented here will aid in the comprehensive analytical and functional characterization of protein micro-heterogeneity, which is crucial for successful development and manufacturing of therapeutic antibodies 相似文献
28.
Janine J. Geerling Yanan Wang Louis M. Havekes Johannes A. Romijn Patrick C. N. Rensen 《PloS one》2013,8(2)
Objective
Central neuropeptide Y (NPY) administration stimulates food intake in rodents. In addition, acute modulation of central NPY signaling increases hepatic production of very low-density lipoprotein (VLDL)-triglyceride (TG) in rats. As hypertriglyceridemia is an important risk factor for atherosclerosis, for which well-established mouse models are available, we set out to validate the effect of NPY on hepatic VLDL-TG production in mice, to ultimately investigate whether NPY, by increasing VLDL production, contributes to the development of atherosclerosis.Research Design and Methods
Male C57Bl/6J mice received an intracerebroventricular (i.c.v.) cannula into the lateral (LV) or third (3V) ventricle of the brain. One week later, after a 4 h fast, the animals received an intravenous (i.v.) injection of Tran35S (100 µCi) followed by tyloxapol (500 mg/kg body weight; BW), enabling the study of hepatic VLDL-apoB and VLDL-TG production, respectively. Immediately after the i.v. injection of tyloxapol, the animals received either an i.c.v. injection of NPY (0.2 mg/kg BW in artificial cerebrospinal fluid; aCSF), synthetic Y1 receptor antagonist (0.5 mg/kg BW in aCSF) or vehicle (aCSF), or an i.v. injection of PYY3–36 (0.5 mg/kg BW in PBS) or vehicle (PBS). GR231118Results
Administration of NPY into both the LV and 3V increased food intake within one hour after injection (+164%, p<0.001 and +367%, p<0.001, respectively). NPY administration neither in the LV nor in the 3V affected hepatic VLDL-TG or VLDL-apoB production. Likewise, antagonizing central NPY signaling by either PYY3–36 or administration did not affect hepatic VLDL production. GR231118Conclusion
In mice, as opposed to rats, acute central administration of NPY increases food intake without affecting hepatic VLDL production. These results are of great significance when extrapolating findings on the central regulation of hepatic VLDL production between species. 相似文献29.
Janine JH Oosterhof G Jolanda Elving Ietse Stokroos Arie van nieuw Amerongen Henny C van der Mei Henk J Busscher 《Biofouling》2013,29(6):347-353
The integrity of biofilms on voice prostheses used to rehabilitate speech in laryngectomized patients causes unwanted increases in airflow resistance, impeding speech. Biofilm integrity is ensured by extracellular polymeric substances (EPS). This study aimed to determine whether synthetic salivary peptides or mucolytics, including N-acetylcysteine and ascorbic acid, influence the integrity of voice prosthetic biofilms. Biofilms were grown on voice prostheses in an artificial throat model and exposed to synthetic salivary peptides, mucolytics and two different antiseptics (chlorhexidine and Triclosan). Synthetic salivary peptides did not reduce the air flow resistance of voice prostheses after biofilm formation. Although both chlorhexidine and Triclosan reduced microbial numbers on the prostheses, only the Triclosan-containing positive control reduced the air flow resistance. Unlike ascorbic acid, the mucolytic N-acetylcysteine removed most EPS from the biofilms and induced a decrease in air flow resistance. 相似文献
30.
Cyanobacterial populations detected on buildings by traditional methods are mainly filamentous, whereas direct microscopy shows that they are principally coccoid morphotypes that often cannot be isolated in culture, but may grow on artificial media when the spatial biofilm relationships are maintained. The polyphasic strategy described here was to select morphologically distinct colonies from rehydrated biofilms for direct DNA amplification, allowing uncultured organisms to be sequenced and their morphology to be characterized by microscopy. DNA data banks currently contain many entries for cyanobacteria of unrecorded morphology, which does not facilitate identification, although genetic variability in a population may be assessed. The sequence homologies of the present biofilm organisms (EMBL accession numbers AJ619681 to 619690) with those in DNA databanks were low, indicating differences between xerophytic cyanobacteria on walls and aquatic species comprising the majority in the databases. Further development of databases for the populations found in this environment, subject to temperature extremes, repeated desiccation and high UV and salt levels, is required. 相似文献