Bibliometric Analysis on the Research of Knowledge Organization in Recent Ten Years

[Purpose/significance] The paper analyzes the 542 literatures related to knowledge organizations in 2007-2016, which are included in the core database of Web of ScienceTM, and aims to grasp the current research situation in this field and provides references for domestic relevant research. [Method/process] Based on the method of bibliometrics, the CiteSpace software was used to analyze and draw the knowledge map from the aspects of annual issuers, authors, countries and research institutions, keywords, co-citation and so on. [Result/conclusion] The results show that authors the most publications are B. Hjorland, I. Dahlberg , V. Broughton etc; the cooperation between researchers and institutions is relatively rare; knowledge organization research areas focus on the knowledge organization itself and classification, ontology and so on; B. Hjorland, H.A. Olson, I. Nonaka and other cited scholars and their cited literatures have high influence on this theme; Knowledge Organization, Journal of Documentation is most important journals for the knowledge organization

Supplementary Material

Supplementary tables and figure

Data from: Growth of maize on mixed nitrate and ammonium promotes auxin synthesis and biomass accumulation

Mixed nitrate (NO3-) and ammonium (NH4+) as nitrogen source can improve plant growth. The underlying mechanism was explored by using metabolomics and transcriptome. Maize plants were grown hydroponically with three nitrogen forms (nitrate, 75/25 nitrate/ammonium and ammonium). Mixed N increased photosynthetic rate compared to nitrate supply, and had the highest leaf area, shoot and root biomass among the three nitrogen treatments. In shoot and root, the concentration of nitrogenous compounds (NH4+, Gln, Asn) and carbohydrates (sucrose, glucose, fructose) in plant with mixed N supply was higher than that with nitrate supply, but lower than that with ammonium supply. The activity of the related enzymes (GS, ASNS, PEPCase, invertase, AGPase) changed accordingly. Specifically, mixed N enhanced IAA synthesis via shikimic acid pathway, as indicated by the higher PEP and tryptophan compared to the other two treatments. The expression of corresponding genes involving IAA synthesis and response were up-regulated. Sole ammonium supply resulted in high level of Gln and Asn, starch, and T6P. It is concluded that, in addition to increase photosynthesis, mixed N supply enhances leaf growth via increasing IAA synthesis to build a big sink for C and N utilization, which, in turn, facilitates further C assimilation and N uptake

Transcriptome raw data from maize (Zhengdan958) is uploaded to SRA database, SRA accession: PRJNA506798.

Transcriptome raw data from maize (Zhengdan958) is uploaded to SRA database, SRA accession: PRJNA506798

Arabidopsis Formin3 Directs the Formation of Actin Cables and Polarized Growth in Pollen Tubes[W]

Cytoplasmic actin cables are the most prominent actin structures in plant cells, but the molecular mechanism underlying their formation is unknown. The function of these actin cables, which are proposed to modulate cytoplasmic streaming and intracellular movement of many organelles in plants, has not been studied by genetic means. Here, we show that Arabidopsis thaliana formin3 (AFH3) is an actin nucleation factor responsible for the formation of longitudinal actin cables in pollen tubes. The Arabidopsis AFH3 gene encodes a 785–amino acid polypeptide, which contains a formin homology 1 (FH1) and a FH2 domain. In vitro analysis revealed that the AFH3 FH1FH2 domains interact with the barbed end of actin filaments and have actin nucleation activity in the presence of G-actin or G actin-profilin. Overexpression of AFH3 in tobacco (Nicotiana tabacum) pollen tubes induced excessive actin cables, which extended into the tubes' apices. Specific downregulation of AFH3 eliminated actin cables in Arabidopsis pollen tubes and reduced the level of actin polymers in pollen grains. This led to the disruption of the reverse fountain streaming pattern in pollen tubes, confirming a role for actin cables in the regulation of cytoplasmic streaming. Furthermore, these tubes became wide and short and swelled at their tips, suggesting that actin cables may regulate growth polarity in pollen tubes. Thus, AFH3 regulates the formation of actin cables, which are important for cytoplasmic streaming and polarized growth in pollen tubes

Metabolites in the shoot and root identified by LC-MS under sole nitrate, 75/25 nitrate and ammonium ratio supply, and sole ammonium supply in 12d for maize (Zhengdan 958) seedlings in hydroponic condition.

Metabolites in the shoot and root identified by LC-MS under sole nitrate, 75/25 nitrate and ammonium ratio supply, and sole ammonium supply in 12d for maize (Zhengdan 958) seedlings in hydroponic condition. Using the R (V3.3.2) XCMS package to identify peaks identification, peaks filtration, peaks alignment. In among, the main parameters are bw=5, ppm=15, peakwidth=c(10,120), mzwid=0.015, mzdiff=0.01, method=”centWave”. Obtain a data matrix including information such as“mass to charge ration, m/z”, retention time and intensity. In among, positive ion mode obtains 16068 precursor molecules and negative ion mode obtains 5259 precursor molecules for each N forms. The data was exported to excel for subsequent analysis. SCK, ST1 and ST2 indicate the metabolites in the shoot of sole nitrate supply, mixed N supply and sole ammonium supply in 12d, respectively. RCK, RT1 and RT2 indicate the metabolites in the root of sole nitrate supply, mixed N supply and sole ammonium supply in 12d, respectively

Involvement of a truncated MADS-box transcription factor ZmTMM1 in root nitrate foraging

AbstractPlants can develop root systems with distinct anatomical features and morphological plasticity to forage nutrients distributed heterogeneously in soils. Lateral root proliferation is a typical nutrient-foraging response to a local supply of nitrate, which has been investigated across many plant species. However, the underlying mechanism in maize roots remains largely unknown. Here, we report on identification of a maize truncated MIKC-type MADS-box transcription factor (ZmTMM1) lacking K- and C-domains, expressed preferentially in the lateral root branching zone and induced by the localized supply of nitrate. ZmTMM1 belongs to the AGL17-like MADS-box transcription factor family that contains orthologs of ANR1, a key regulator for root nitrate foraging in Arabidopsis. Ectopic overexpression of ZmTMM1 recovers the defective growth of lateral roots in the Arabidopsis anr1 agl21 double mutant. The local activation of glucocorticoid receptor fusion proteins for ZmTMM1 and an artificially truncated form of AtANR1 without the K- and C-domains stimulates the lateral root growth of the Arabidopsis anr1 agl21 mutant, providing evidence that ZmTMM1 encodes a functional MADS-box that modulates lateral root development. However, no phenotype was observed in ZmTMM1-RNAi transgenic maize lines, suggesting a possible genetic redundancy of ZmTMM1 with other AGL17-like genes in maize. A comparative genome analysis further suggests that a nitrate-inducible transcriptional regulation is probably conserved in both truncated and non-truncated forms of ZmTMM1-like MADS-box transcription factors found in grass species