Fei Xiong

Yangzhou University, Chiang-tu, Jiangsu Sheng, China

Are you Fei Xiong?

Claim your profile

Publications (13)21.03 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background The objectives of this study were (1) to characterize structural development of starch granule in pericarp and endosperm during wheat caryopsis growth (2) to compare physicochemical properties of starches in pericarp and endosperm (3) to further find out the relationships between pericarp starches and endosperm starches. Wheat pericarp and endosperm at different development stages were observed by light microscopy and scanning electron microscopy, respectively. Structural properties of starches were determined using X-ray power diffraction, and 13C Solid Nuclear Magnetic Resonance.ResultsPericarp starch granules (PSG) accumulated in amyloplasts and chloroplasts, and showed a typical accumulation peak at 5 days after fertilization (DAF), and then gradually decomposed during 5–22 DAF. PSG in the abdominal region showed a higher rate of decomposition compared to the dorsal region of pericarp. Endosperm starch granules (ESG) accumulated in amyloplasts, and occurred in endosperm cells at 5 DAF, then rapidly enriched the endosperm cells until 22 DAF. Compared with ESG, PSG were compound granules of irregular shape and small size distribution. The results also suggested lower amylose content and V-type single-helix content and higher proportions of double-helices, for PSG compared to ESG.Conclusion Based on the structural development of PSG and ESG, we speculated that the saccharides resulting from decomposition of PSG on one hand enabled the pericarp to survive before maturity of wheat caryopsis, and on the other hand provided extra nutrition for the growth of ESG.
    Journal of the Science of Food and Agriculture 04/2014; · 1.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study provided visual evidence of a nitrogen effect on starch granules (SGs) in wheat endosperm. Winter wheat (Titicum aestivum L.) cultivar Xumai 30 was cultured under no nitrogen (control) and 240 kg ha− 1 of nitrogen applied at the booting stage. The number, morphology, and size of A- and B-type SGs in subaleurone of dorsal endosperm (SDE), center of dorsal endosperm (CDE), modified aleurone (MA), subaleurone of ventral endosperm (SVE), and center of ventral endosperm (CVE) were observed under light and electron microscopes. (1) The distribution of SGs in SDE was similar to that in SVE, the distributions of SGs in CDE and CVE were similar, but the distribution of SGs in MA was different from those in the other four endosperm regions. The number of SGs in the five endosperm regions was in the order SDE > CDE > SVE > CVE > MA. (2) Nitrogen increased the number of A- and B-type SGs in SDE and SVE. Nitrogen also increased the number of B-type SGs but decreased the number of A-type SGs in CDE and CVE. Nitrogen decreased the numbers of A-type and B-type SGs in MA. The results suggest that increased N fertilizer application mainly increased the numbers of small SGs and decreased the numbers of large SGs, but that the results varied in different regions of the wheat endosperm.
    The Crop Journal. 01/2014; 2(1):46–54.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The development of pericarp, seed coat, starchy endosperm and aleurone of the rice caryopsis was investigated, histochemically and structurally, from the time of flowering to maturity. The results showed that during its growth, the maximum length of the caryopsis was attained first, followed by width and then thickness. Histochemical examination of the caryopsis showed that starch was mainly accumulated in the endosperm, but the endosperm showed no metabolic activity, while embryo and pericarp contained a few starch grains, and embryo and aleurone were strongly active. Aleuronic cells contained many aleurone grains and spherosomes, and aleurone in the dorsal region developed earlier and contained more layers of cells. Amyloplasts in endosperm contained many starch granules and were spherical at early stages but polyhedric at late stages. The protein bodies appeared later than amyloplasts, and the number of protein bodies in subaleurone was greater than those in the starchy endosperm. The white-belly portion of endosperm might be relative to the status of amyloplast development.
    Rice Science 01/2014; 21(3):142–149.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of the present work was to reveal the histological changes of protein bodies (PBs) in the developing wheat endosperm under nitrogen (N) treatment. For this purpose, the development and accumulation of PBs in the dorsal and ventral regions of wheat endosperm affected by N application at booting stage were investigated using light microscopy and Image-Pro Plus 6.0 software. The endosperm without N treatment contained many smaller PBs that were scattered in endosperm cells in an unordered pattern, whereas the endosperm with N treatment contained many larger PBs or aggregations that were concentrated in a certain region of endosperm cells. The amount and relative areas of PBs in wheat varieties cvs. Xumai 30 and Yangmai 13 were significantly increased by N application. However, the cultivars differed with the degree of response to N being cv. Xumai 30 > cv. Yangmai 13. These differences also varied with position in the endosperm in the order ventral > dorsal region. The initiation of PBs occurred 3 days earlier in N-treated endosperm than the control.
    Molecular Biology Reports 12/2013; · 2.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The wheat aleurone is formed from surface endosperm cells, and its developmental status reflects its biogenesis, structural characteristics, and physiological functions. In this report, wheat caryopses at different development stages were embedded in Spurr's low-viscosity embedding medium for observation of the development of aleurone cells (ACs) by light microscopy, scanning electron microscopy, and fluorescence microscopy, respectively. According to their structures and physiological characterization, the ACs development process was divided into five stages: endosperm cellulization, spherosome formation, aleurone grain formation, filling material proliferation, and maturation. Furthermore, ACs in different parts of the caryopsis formed differently. ACs near the vascular bundle developed earlier and formed transfer cells, but other ACs formed slowly and did not form transfer cells. ACs on the caryopsis backside were a regular square shape; however, ACs in the caryopsis abdomen were mainly irregular. There were also differences in development between wheat varieties. ACs were rectangular in hard wheat but square in soft wheat. ACs were larger and showed a greater degree of filling in hard compared to soft wheat. The storage materials in ACs were different compared to inner endosperm cells (IECs). The concentrations of minerals such as sodium, magnesium, silicon, phosphorus and potassium were higher in ACs than in IECs. ACs contained many aleurone grains and spherosomes, which store lipids and mineral nutrients, respectively. The cell nucleus did not disappear and the cells were still alive during aleurone maturation. However, IECs were dead and mainly contained amyloplast and protein bodies, which store starch and protein, respectively. Overall, the above results characterized major structural features of aleurone and revealed that the wheat aleurone has mainly four functions.
    Molecular Biology Reports 09/2013; · 2.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: KEY MESSAGE : The cytological and physiological features of developing wheat pericarp were clearly characterized in this report. Our results may be helpful to articulate the functions of pericarp during the seed development. Although wheat pericarp has been well studied, knowledge of the sequence of events in the process of pericarp development is incomplete. In the present study, the structural development process of wheat (Triticum aestivum L.) pericarp was investigated in detail using resin microtomy and microscopy. Chlorophyll contents, and photosynthetic and respiratory rates, in pericarp were determined using spectrophotometer and an oxygen electrode, respectively. Mineral nutrient contents were also determined using scanning electron microscopy. The main results are as follows: (1) based on the structures and physiological characteristics observed, the developmental process of pericarp was divided into four stages, growth, formation, extinction and maturation stages, pericarp exhibited specific features at each stage. (2) Pericarp development differed in different parts, or varieties, of wheat. The dorsal pericarp had fewer starch grains and slower rates of apoptosis than the abdominal mesocarp. The cross cells in dorsal pericarp had an irregular outline. When compared with soft wheat cv. Yangmai 11, mesocarp cells in hard wheat cv. Xumai 30 had more starch grains, larger cell size and longer development duration. (3) The chlorophyll content, photosynthesis rate and respiratory rate in pericarp increased gradually, reaching a maximum about 16 days after anthesis, and later decreased continually. The photosynthetic rate in pericarp was lower than the respiration rate. (4) The contents of mineral elements in pericarp, such as calcium, zinc, iron and potassium were higher than those in the inner endosperm. The data indicate that wheat pericarp has many functions, e.g. protection, photosynthesis, mineral accumulation, synthesis and degradation of starch.
    Plant Cell Reports 04/2013; · 2.94 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 2,3-Dihydroxybiphenyl-1,2-dioxygenase plays an important role in the degradation of polychlorinated biphenyls. The gene (BsbphCI) encoding a 2,3-DHBP dioxygenase from Bacillus sp. JF8 is 960 bp. We synthesized a 960 bp BsbphCI gene encoding a 2,3-DHBP dioxygenase derived from Bacillus sp. JF8 and expressed it in Escherichiacoli. The recombinant protein was about 36 kDa, confirmed by SDS-PAGE. The concentration of the purified protein was about 1.8 mg/mL. With 2,3-DHBP as a substrate, the optimal temperature for enzyme activity at pH 8.5 was 50 °C. The optimal pH for the 2,3-DHBP dioxygenase was 8.5. The enzyme retained 33% activity after heating at 60 °C for 60 min. We found that Cu(2+), K(+), Zn(2+), Mg(2+), Ni(2+), Co(2+), and Cd(2+) activated the enzyme. However, Ca(2+), Fe(2+), Li(+), and Cr(3+) inhibited it. Enzyme activity was reduced by exposure to H(2)O(2), SDS, and KI. The results of HPLC indicated that the transgenic E. coli strain with the BsbphCI gene degraded 2,3-DHBP more quickly than the wild type strain.
    Biochemical and Biophysical Research Communications 02/2012; 419(2):339-43. · 2.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: As one of the persistent organic pollutants, polychlorinated biphenyls are harmful to the environment and humans. Biodegradation is the most potential way to remove PCBs. Biodegradation can mainly be divided into microbial degradation, phytoremediation, plant and microbial combined remediation. Here, we introduced isolation of the PCBs-degrading strains, cloning and modification of the related degradation genes. Additionally, on the other hand, the natural remediation of plant, plant and microbial combined remediation, plant transgenic remediation were described.
    Hereditas (Beijing) 03/2011; 33(3):219-27.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Throughout its development, common wheat, Triticum aestivum responds to different kinds of adverse abiotic and biotic stress by expressing specific genes that allow it to adapt to these stresses. In this process, genes in the AP2/ERF family encode transcriptional regulators involved in diverse developmental and physiological processes play critical roles. Here, we established an extensive picture of the AP2/ERF family genes in wheat. From 960, 174 ESTs of T. aestivum, 117 putative AP2/ERF family genes were identified by in silico analysis based on the presence of the conserved AP2/ERF domain amino acid sequence of Arabidopsis thaliana. Based on the model species A. thaliana, the AP2/ERF TFs from T. aestivum were classified into five subfamilies with the following number of members: DREB (57), ERF (47), AP2 (9), RAV (3) and Soloist (1). Using the available EST information as a source of expression data, the putative AP2/ERF family genes from T. aestivum were detected in nine kinds of tissues. Transcripts of the genes were shown to be most abundant in leaves, followed by roots and seeds, and the least abundant in stem. Most of the T. aestivum AP2/ERF family genes showed some tissue specificity.
    Molecular Biology Reports 02/2011; 38(2):745-53. · 2.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A 2,3-dihydroxybiphenyl (2,3-DHBP) dioxygenase gene from a Rhodococcus sp. strain, named RrbphCI and involved in the degradation of polychlorinated biphenyls (PCBs), was synthesized. RrbphCI was expressed in Escherichia coli and its encoded enzyme was purified. SDS-PAGE analysis indicated that the size of the protein encoded by RrbphCI was about 32 kDa. The activity of the 2,3-DHBP dioxygenase was 82.8 U/mg when the substrate was 2,3-DHBP, with optimum pH 8.0 at 30°C, and optimum temperature was 40°C at pH 8.0. The RrbphCI gene was transformed into Pseudomonas putida strain EG11, to determine the ability of the enzyme to degrade 2,3-DHBP. The wild type EG11 degraded 61.86% of supplied 2,3-DHBP and the transformed EG11 (hosting the RrbphCI gene) utilized 52.68% after 2 min of treatment at 30°C. The overexpressed and purified enzyme was able to degrade 2,3-DHBP. The 2,3-DHBP dioxygenase is a key enzyme in the PCB degradation pathway. RrbphCI and its encoded 2,3-DHBP dioxygenase may have transgenic applications in bioremediation of PCBs.
    Molecular Biology Reports 11/2010; 38(7):4303-8. · 2.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: As one of China's great metropolises, Shanghai is vulnerable to various forms of industrial and agricultural contamination associated with its development. Polychlorinated biphenyls (PCBs) are man-made chemicals that never existed in nature until the 1900s when they started to be released into the environment. PCBs are hazardous environmental contaminants that bind strongly to soil. In this study, four soil samples were screened for the presence of PCB-degrading bacteria. The 16 S rDNAs were amplified from those genomes and the products (~1.5 kb) were purified and sequenced for the isolation and identification of bacterial species. Four Pseudomonas strains (strain 1-212 from sample 1; strain 2-241 from sample 2; strain 3-318 from sample 3; and strain 4-150 from sample 4) were selected for analysis by HPLC. Setting the content of the biphenyl in CK as 100%, the biphenyl contents was 2.32% in 1-212, 73.11% in 2-241, 69.83% in 3-318, and 86.16% in 4-150. The results of this study suggest directions for future research, including genetic screening, cloning and restructuring, and provide guidance for the cultivation of PCBs-degrading bacteria.
    Current Microbiology 11/2010; 61(5):477-83. · 1.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A transcription factor (TF) is a protein that binds to specific DNA sequences and thereby controls transcription. A large number of TFs are found in plants. The AP2/ERF family of TFs contain the AP2 DNA-binding domain, which play important roles in transcriptional regulation in plant life. To understand the AP2/ERF family TFs of maize, the discovery, phylogeny and expression pattern analysis of AP2-like genes from maize were described. A total of 167 AP2-like genes were identified by in silico cloning using the amino acid sequence of AP2/ERF family TFs from Arabidopsis thaliana as the probe. The maize AP2-like genes identified were orthologous to those TFs in Arabidopsis. The AP2/ERF TFs from maize were classified into four subfamilies (DREB, ERF, AP2 and RAV) and a Soloist. Using the EST information of maize as a source of expression data, those AP2-like genes from maize were detected in different plant tissues. KeywordsTranscription factor-AP2/ERF-Expression profile- Arabidopsis thaliana -Maize
    Plant Growth Regulation 01/2010; 62(1):51-58. · 1.67 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The 2, 3-dihydroxybiphenyl-1,2-dioxygenase, which can degrade the 2,3-dihydroxybiphenyl, was encoded by a synthesized PsbphCI gene. The PsbphCI gene was transformed into Escherichia coli and the encoding protein purified, had a molecular mass of ∼32 kDa as determined by SDS-PAGE. The optimum pH for the purified enzyme at 20°C was 9.0, and the optimal temperature at pH 8.0 was 30°C. Subsequently, the PsbphCI gene was transformed into Pseudomonas putida sp. to verify the degradation of 2,3-dihydroxybiphenyl by HPLC. The transgenic EG11 strain degraded 65.20% of the 2,3-DHBP after 2 minutes at 30°C, while the wild-type EG11 strain degraded only 37.75%. This study provides guidance for the cultivation of bioengineered biphenyl/PCBs-degrading bacteria which can be applied to the biodegradation of environmental biphenyl/PCBs contamination.
    Molecular and Cellular Toxicology 8(4). · 0.72 Impact Factor

Publication Stats

30 Citations
21.03 Total Impact Points

Institutions

  • 2010–2014
    • Yangzhou University
      • College of Bioscience and Biotechnology
      Chiang-tu, Jiangsu Sheng, China
  • 2012
    • Nanjing Agricultural University
      • State Key Laboratory of Crop Genetics and Germplasm Enhancement
      Nanjing, Jiangsu Sheng, China
  • 2010–2011
    • Shanghai Academy of Agricultural Sciences
      Shanghai, Shanghai Shi, China