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Maize (Zea mays) requires substantial amounts of nitrogen, posing a challenge for its cultivation. Recent work discovered that some ancient Mexican maize landraces harbored diazotrophic bacteria in mucilage secreted by their aerial roots. To see if this trait is retained in modern maize, we conducted a field study of aerial root mucilage (ARM) in 258 inbred lines. We observed that ARM secretion is common in modern maize, but the amount significantly varies, and only a few lines have retained the nitrogen‐fixing traits found in ancient landraces. The mucilage of the high‐ARM inbred line HN5‐724 had high nitrogen‐fixing enzyme activity and abundant diazotrophic bacteria. Our genome‐wide association study identified 17 candidate genes associated with ARM across three environments. Knockouts of one candidate gene, the subtilase family gene ZmSBT3, confirmed that it negatively regulates ARM secretion. Notably, the ZmSBT3 knockout lines had increased biomass and total nitrogen accumulation under nitrogen‐free culture conditions. High ARM was associated with three ZmSBT3 haplotypes that were gradually lost during maize domestication, being retained in only a few modern inbred lines such as HN5‐724. In summary, our results identify ZmSBT3 as a potential tool for enhancing ARM, and thus nitrogen fixation, in maize. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have received much attention and application in transparent electrodes, wearable electronic devices, and sensors. The hope is for these nanowires to eventually replace the most commonly used transparent electrode material—indium tin oxide (ITO). However, electrospinning used for the preparation of AgNWs on a large scale is limited by its low productivity and high electric field, while the alcohol-thermal method is limited to mixing by-product silver nanoparticles in silver nanowires. We demonstrate a novel and simple centrifugal spinning approach in order to successfully fabricate ultra-long silver microfibers based on AgNO3 and polyvinyl pyrrolidone (PVP). The centrifugal-spun precursor fiber and silver fiber can be prepared to as thin as 390 and 310 nm, respectively. Annealed fibers show typical nanostructures with grains down to a minimum size of 51 nm. Combinations of different parameters, including concentrations of PVP, needle size, and annealing temperature are also investigated, in order to optimize the spinning process of ultra-long silver microfibers. The feasibility of preparing silver microfibers by centrifugal spinning is preliminarily verified, examining prospects for mass production. Furthermore, numerous strategies related to assisting the creation of silver nanofibers using centrifugal spinning are presented as possibilities in future development. [ABSTRACT FROM AUTHOR]

Protein–protein interaction (PPI) plays a crucial role in most biological processes, including signal transduction and cell apoptosis. Importantly, the knowledge of PPIs can be useful for identification of multimeric protein complexes and elucidation of uncharacterized protein functions. Arabidopsis thaliana, the best‐characterized dicotyledonous plant, the steadily increasing amount of information on the levels of its proteome and signaling pathways is progressively enabling more researchers to construct models for cellular processes for the plant, which in turn encourages more experimental data to be generated. In this study, we performed an overview analysis of the 10 major organelles and their associated proteins of the dicotyledonous model plant Arabidopsis thaliana via PPI network, and found that PPI may play an important role in organelle communication. Further, multilocation proteins, especially phosphorylation‐related multilocation proteins, can function as a "needle and thread" via PPIs and play an important role in organelle communication. Similar results were obtained in a monocotyledonous model crop, rice. Furthermore, we provide a research strategy for multilocation proteins by LOPIT technique, proteomics, and bioinformatics analysis and also describe their potential role in the field of plant science. The results provide a new view that the phosphorylation‐related multilocation proteins play an important role in organelle communication and provide new insight into PPIs and novel directions for proteomic research. The research of phosphorylation‐related multilocation proteins may promote the development of organelle communication and provide an important theoretical basis for plant responses to external stress. [ABSTRACT FROM AUTHOR]

Protein extracts obtained from cells or tissues often require removal of interfering substances for the preparation of high-quality protein samples in proteomic analysis. A number of protein extraction methods have been applied to various biological samples. TCA/acetone precipitation and phenol extraction, a common method of protein extraction, is thought to minimize protein degradation and activity of proteases as well as reduce contaminants like salts and polyphenols. However, the TCA/acetone precipitation method relies on the complete pulverization and repeated rinsing of tissue powder to remove the interfering substances, which is laborious and time-consuming. In addition, by prolonged incubation in TCA/acetone, the precipitated proteins are more difficult to re-dissolve. We have described a modified method of TCA/acetone precipitation of plant proteins for proteomic analysis. Proteins of cells or tissues were extracted using SDS-containing buffer, precipitated with equal volume of 20% TCA/acetone, and washed with acetone. Compared to classical TCA/acetone precipitation and simple acetone precipitation, this protocol generates comparable yields, spot numbers, and proteome profiling, but takes less time (ca. 45 min), thus avoiding excess protein modification and degradation after extended-period incubation in TCA/acetone or acetone. The modified TCA/acetone precipitation method is simple, fast, and suitable for proteomic analysis of various plant tissues in proteomic analysis. [ABSTRACT FROM AUTHOR]

The cell wall is the most striking feature that distinguishes plant cells from animal cells. It plays an essential role in cell shape, stability, growth and protection. Despite being present in small amounts, cell wall proteins (CWPs) are crucial components of the cell wall. The cell wall proteome generally consists of sensu stricto CWPs, apoplast proteins and extracellular secreted proteins. Currently, there is a need for the bioinformatics analysis of a tremendous number of protein sequences that have been generated from genomic, transcriptomic and proteomics research. Compared with intracellular proteins, the location prediction of CWPs is challenging because many aspects of these proteins have not been experimentally characterized, and there are no CWP-trained, specific predictors available. By introducing the biological relevance (particularly molecular aspects) of the cell wall and CWPs, we critically evaluated the accuracy of 16 state-of-the-art predictors and classical predictors for the prediction of CWPs using an independent database of Arabidopsis and rice proteins. All experimentally verified CWPs and non-CWPs were retrieved from the UniProt Knowledgebase. Based on the evaluation, we currently recommend the predictors mGOASVM, HybridGO-Loc and FUEL-mLoc for CWPs. Furthermore, we outlined the public databases that can be used to cross-reference the subcellular location of CWPs. We illustrate a flowchart of the subcellular location prediction and a cross-reference of possible CWPs. Finally, we discuss challenges and perspectives in the bioinformatics analysis of CWPs. It is hoped that this article will provide practical guidance regarding CWPs for nonspecialists and provide insight for bioinformatics experts to develop computational tools for CWPs. [ABSTRACT FROM AUTHOR]

In this paper, by precisely tuning the structure of composite, a 3D silkworm cocoon-like composite material based on reduced graphene oxide (RGO) and Z-CoO (with a ZIF-67 as precursor) are prepared through a in situ hydrothermal method. This Z-CoO/RGO nanocomposite exhibits a highly opened nanostructure and high conductive capability. The electrochemical performance reveals that an outstanding mass specific capacity (275 F g−1 at current density of 1 A g−1), which is much higher than the pure ZIF-67 with 2.7 F g−1, and excellent resistance characteristic are obtained due to the excellent synergistic effect between the MOFs and RGO. Moreover, a hybridized asymmetric supercapacitor with Z-CoO/RGO as anode and active carbon as cathode is constructed. The device shows ultra-low resistance (the equivalent-series resistance and the charge-transfer resistance are 1.13 Ω and 0.43 Ω, respectively) and stable cycle life about 1000 times is observed. This Z-CoO/RGO electrode also presents high current loading performance for possible high-power density type devices. Our work reveals that the straightforward hydrothermal treatment is a promising method for the preparation of dedicated MOFs complex nanostructure for high performance supercapacitor electrode applications. Image 1 • The Z-CoO/RGO has been firstly fabricated through a in situ hydrothermal method. • The Z-CoO/RGO obtained outstanding mass specific capacity and high conductivity. • The device with Z-CoO/RGO shows ultra-low resistance and stable storage performance. [ABSTRACT FROM AUTHOR]

Objective: To detect the expression of differentially expressed proteins in serum of patients with allergic rhinitis who were allergic to dust mites before and after 6-day rush immunotherapy. The three differentially expressed proteins, CRP, CTHRC1 and WDR89, were detected and identified. The immunoregulatory effects and significance of these three differentially expressed proteins in rush immunotherapy of allergic rhinitis were analyzed and discussed. Method: The serum samples of 15 patients with allergic rhinitis, 15 patients with rush immunotherapy and 10 patients with healthy control group were collected. The samples were studied by isobaric tags for relative and absolute quantitation（iTRAQ） technique. The related differential proteins were determined by two-dimensional gel electrophoresis and mass spectrometry, and the rationality of the screened differential proteins was tested and verified by Cluster3.0 software and Java TreeView software. Finally, the selected CRP, CTHRC1 and WDR89 proteins were identified by enzyme-linked immunosorbent assay（ELISA）. Result: In this study, 893 proteins were detected and 53 differential proteins were identified. Compared with healthy control group, 24 proteins which was statistically significant were found in allergic rhinitis group, which were closely related to the occurrence of allergic rhinitis, including 10 up-regulated proteins and 14 down-regulated proteins. Compared with the allergic rhinitis group, patients with allergic rhinitis underwent 6 days of rush immunotherapy. There were 29 proteins whose expression of proteins with a difference of P value of less than 0.05 and 1.2 times higher, which were related to the effect after the incremental phase of rush immunotherapy was completed, of which 12 were up-regulated and 17 were down-regulated. Compared with healthy control group, the expression of up-regulated of allergic rhinitis group and the expression of down-regulated protein after 6 days of rush immunotherapy were CTHRC1, WDR89; Compared with healthy control group, AR group was down-regulated and the expression of up-regulated protein after 6 days of rush immunotherapy was CRP. CRP, CTHRC1 and WDR89 proteins were identified by enzyme linked immunosorbent assay（ELISA）, and it was found that the differential expression of CTHRC1 and WDR89 in AR and RIT was statistically significant（ P <0.05）, but the differential expression of serum CRP in AR and RIT was not statistically significant（ P >0.05）. Conclusion: Serum protein CTHRC1 and WDR89 are closely related to the pathogenesis of allergic rhinitis, and played a role in the regulation of rush immunotherapy, while serum protein CRP has no significant effect on AR and RIT., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Maize is one of the most widely cultivated crops. It accumulates a large quantity of seed storage proteins, which are important for seed development and germination, and contribute to the nutritional quality of seeds. Based on solubility, the storage proteins are divided into albumins (water-soluble), globulins (salt-soluble), prolamins (alcohol-soluble), and glutelins (acid- or alkali-soluble). Maize hybrids are cultivated due to the superior performance of F 1 hybrids than that of their parents, a phenomenon known as heterosis. However, the accumulation patterns of seed storage proteins in maize embryos between the hybrids and their parental inbred lines have not been compared. In the present study, two elite inbred lines of China, Zheng 58 and Chang 7-2, and their reciprocal hybrids (Zheng 58 × Chang 7-2 and Chang 7-2 × Zheng 58) were used to explore parental influences on the accumulation patterns of seed storage proteins in maize embryos. For this purpose, we focused on seed salt-soluble proteins (SSPs) in our experiments. The SSPs were selectively extracted from maize mature embryos after extensive removal of water-soluble albumin and separated using two-dimensional gel electrophoresis (2-DE), followed by mass spectrometry analysis. Our results indicated that the 2-DE SSP profiles of hybrids closely resembled those of their maternal parent rather than the paternal parent. In other words, 2-DE SSP profiles of Zheng 58 × Chang 7-2 were more similar those of Zheng 58 whereas such profiles of Chang 7-2 × Zheng 58 were more similar to those of Chang 7-2 although the 2-DE profiles of all four maize types were quite similar. In total, 12 relatively abundant SSPs spots representing five kinds of proteins were identified, of which nine protein spots displayed non-additive accumulation in at least one hybrid. This study provided additional data on dominance and partial dominance effects on maize hybrids embryos. Besides, earlier studies on accumulation profiles of globulin-1 (also known as vicilin), which is one of the most abundant globulins in maize embryos, also support the above results. This study would be helpful in revealing the mechanisms underlying SSPs accumulation patterns in the hybrids.