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41.
Grain size and weight are important components of a suite of yield‐related traits in crops. Here, we showed that the CRISPR‐Cas9 gene editing of TaGW7, a homolog of rice OsGW7 encoding a TONNEAU1‐recruiting motif (TRM) protein, affects grain shape and weight in allohexaploid wheat. By editing the TaGW7 homoeologs in the B and D genomes, we showed that mutations in either of the two or both genomes increased the grain width and weight but reduced the grain length. The effect sizes of mutations in the TaGW7 gene homoeologs coincided with the relative levels of their expression in the B and D genomes. The effects of gene editing on grain morphology and weight traits were dosage dependent with the double‐copy mutant showing larger effect than the respective single copy mutants. The TaGW7‐centered gene co‐expression network indicated that this gene is involved in the pathways regulating cell division and organ growth, also confirmed by the cellular co‐localization of TaGW7 with α‐ and β‐tubulin proteins, the building blocks of microtubule arrays. The analyses of exome capture data in tetraploid domesticated and wild emmer, and hexaploid wheat revealed the loss of diversity around TaGW7‐associated with domestication selection, suggesting that TaGW7 is likely to play an important role in the evolution of yield component traits in wheat. Our study showed how integrating CRISPR‐Cas9 system with cross‐species comparison can help to uncover the function of a gene fixed in wheat for allelic variants targeted by domestication selection and select targets for engineering new gene variants for crop improvement.  相似文献   
42.
Evidence for specific and direct bacterial product recognition through toll-like receptors (TLRs) has been emphasized recently. We analyzed lipopeptide analogues and enterobacterial lipopolysaccharide (eLPS) for their potential to activate cells through TLR2 and TLR4. Whereas bacterial protein palmitoylated at its N-terminal cysteine and N-terminal peptides derived thereof are known to induce TLR2-mediated cell activation, a synthetic acylhexapeptide mimicking a bacterial lipoprotein subpopulation for which N-terminal trimyristoylation is characteristic (Myr(3)CSK(4)) activated cells not only through TLR2 but also through TLR4. Conversely, highly purified eLPS triggered cell activation through overexpressed TLR2 in the absence of TLR4 expression if CD14 was coexpressed. Accordingly, TLR2(-/-) macrophages prepared upon gene targeting responded to Myr(3)CSK(4) challenge, whereas TLR2(-/-)/TLR4(d/d) cells were unresponsive. Through interferon-gamma (IFNgamma) priming, macrophages lacking expression of functional TLR4 and/or MD-2 acquired sensitivity to eLPS, whereas TLR2/TLR4 double deficient cells did not. Not only TLR2(-/-) mice but also TLR4(-/-) mice were resistant to Myr(3)CSK(4) challenge-induced fatal shock. d-Galactosamine-sensitized mice expressing defective TLR4 or lacking TLR4 expression acquired susceptibility to eLPS-driven toxemia upon IFNgamma priming, whereas double deficient mice did not. Immunization toward ovalbumin using Myr(3)CSK(4) as adjuvant was ineffective in TLR2(-/-)/TLR4(-/-) mice yet effective in wild-type, TLR2(-/-), or TLR4(-/-) mice as shown by analysis of ovalbumin-specific serum Ig concentration. A compound such as Myr(3)CSK(4) whose stimulatory activity is mediated by both TLR2 and TLR4 might constitute a preferable adjuvant. On the other hand, simultaneous blockage of both of the two TLRs might effectively inhibit infection-induced pathology.  相似文献   
43.
Interleukin-2 (IL-2) is a potent molecule in cancer therapy. Clinical application, however, is limited due to its strong side effects during the treatment. We developed an IL-2 variant (IL-2v) immunocytokine to circumvent the drawbacks of the current IL-2 therapy. During the production of the IL-2v immunocytokine in Chinese hamster ovary (CHO) cells, molecules with fragmented IL-2v and therefore reduced cytokine activity can be observed. To control product fragmentation different production process conditions were investigated. By shifting temperature or pH after the cell growth phase to lower values, fragmented species can be reduced from 10% to 12% to about 4%. However, with the adopted process conditions, the effective titer is decreased concomitantly. Moreover, fermentation length and inoculation cell density are parameters to adjust fragmentation and effective titer. A suitable method for efficient process optimization is the design of experiment approach. With this procedure, novel optimal values for temperature, pH value, harvest day, and inoculation cell densities were proposed and tested subsequently. In comparison to the former process, the improved process reduces fragmentation by 66% while keeping the effective titer comparable. In summary, these findings will help to control fragmentation in CHO production processes of different IL-2v or IL-2 containing therapeutic proteins.  相似文献   
44.
Biological Trace Element Research - We analyzed cobalt (Co), chromium (Cr), and lead (Pb) concentrations in human semen and catalase CAT activity in seminal plasma and the effects of their...  相似文献   
45.
Compared with other SARS-related coronaviruses (SARSr-CoVs), SARS-CoV-2 possesses a unique furin cleavage site (FCS) in its spike. This has stimulated discussion pertaining to the origin of SARS-CoV-2 because the FCS has been observed to be under strong selective pressure in humans and confers the enhanced ability to infect some cell types and induce cell–cell fusion. Furthermore, scientists have demonstrated interest in studying novel cleavage sites by introducing them into SARSr-CoVs. We review what is known about the SARS-CoV-2 FCS in the context of its pathogenesis, origin, and how future wildlife coronavirus sampling may alter the interpretation of existing data.  相似文献   
46.
Alterations in haptoglobin (Hp) glycosylation were examined in the plasma of the first patient with carbohydrate-deficient glycoprotein syndrome (CDGS) who was described in Poland. Hp concentration in the CDGS patient plasma was low (240mg/l) and the Hp phenotype was shown to be 2-2. Three glycoforms of the Hp subunit were observed in SDS-PAGE in CDGS. The densitometric analysis and molecular weight determinations suggested that 50% of glycoforms were fully glycosylated; 30% contained three out of four and 20% only two out of four glycan units compared to those that are present in Hp derived from healthy people. Results with lectins (concanavalin A and Sambucus nigra, Maackia amurensis and Alleuria aurantia agglutinins) indicate that all three glycoforms of subunit of CDGS-Hp contained biantennary complex glycans terminated with 2,6 bound sialic acid, but without fucose or 2,3 linked sialic acid. Hp glycosylation abnormalities described in this work suggest that this case was a type I carbohydrate-deficient glycoprotein syndrome.  相似文献   
47.
Conventional functional monomers together with fluorescent monomer, trans-4-[p-(N,N-dimethylamino)styryl]-N-vinylbenzylpyridinium chloride (vb-DMASP), were copolymerised in the presence of a target molecule, nucleotide-cAMP that acted as a molecular template. The polymer was copolymerised in thin-layer films. After removal of the template the functionalised cavities that exist in the fluorescent material are able to specifically bind the template. Subsequent adsorption of the template-cAMP causes quenching of fluorescence of the polymer. The specific photochemical processes accompanying the template adsorption are discussed further. The imprinted polymers monitored by both steady-state and time-resolved fluorescence techniques show specificity and selectivity of binding of the template on the imprinted functionalised cavities.  相似文献   
48.
The Arabidopsis proline-rich extensin-like receptor kinase (PERK) family consists of 15 predicted receptor kinases. A comprehensive expression analysis was undertaken to identify overlapping and unique expression patterns within this family relative to their phylogeny. Three different approaches were used to study AtPERK gene family expression, and included analyses of the EST, MPSS and NASCArrays databases as well as experimental RNA blot analyses. Some of the AtPERK members were identified as tissue-specific genes while others were more broadly expressed. While in some cases there was a good association between these different expression patterns and the position of the AtPERK members in the kinase phylogeny, in other cases divergence of expression patterns was seen. The PERK expression data identified by the bioinformatics and experimental approaches were found generally to show similar trends and supported the use of data from large-scale expression studies for obtaining preliminary expression data. Thus, the bioinformatics survey for ESTs and microarrays is a powerful comprehensive approach for obtaining a genome-wide view of genes in a multigene family.  相似文献   
49.
50.
Alpha-synuclein is the main component of the intracellular protein aggregates in neurons of patients with Parkinson's disease. The occurrence of the disease is associated with oxidative damage. Although it is known that peroxidative chemistry leads to the aggregation of alpha-synuclein in vitro, the specific amino acid types of alpha-synuclein involved in this type of aggregation have not been identified. We show, using human cytochrome c plus H(2)O(2) as the source oxidative stress, that the tyrosines of alpha-synuclein are required for aggregation. The studies reveal the chemical basis for a crucial step in the aggregation process.  相似文献   
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