Cover illustration
Shoot branching is an important trait of crop and horticultural plants. It is jointly regulated by complex interactions among hormones, development, and environmental factors. In this paper, we reviewed current perspectives on shoot branching regulation. It is an overview of plant shoot branching regulatory network, involving long distance systemic signals and local gene response to external environmental factors, such as decapitation and shading (The background picture was p [Detail] ...
Increased demand for liquid transportation fuels, environmental concerns and depletion of petroleum resources requires the development of efficient conversion technologies for production of second-generation biofuels from non-food resources. Thermochemical approaches hold great potential for conversion of lignocellulosic biomass into liquid fuels. Direct thermochemical processes convert biomass into liquid fuels in one step using heat and catalysts and have many advantages over indirect and biological processes, such as greater feedstock flexibility, integrated conversion of whole biomass, and lower operation costs. Several direct thermochemical processes are employed in the production of liquid biofuels depending on the nature of the feedstock properties: such as fast pyrolysis/liquefaction of lignocellulosic biomass for bio-oil, including upgrading methods, such as catalytic cracking and hydrogenation. Owing to the substantial amount of liquid fuels consumed by vehicular transport, converting biomass into drop-in liquid fuels may reduce the dependence of the fuel market on petroleum-based fuel products. In this review, we also summarize recent progress in technologies for large-scale equipment for direct thermochemical conversion. We focus on the technical aspects critical to commercialization of the technologies for production of liquid fuels from biomass, including feedstock type, cracking catalysts, catalytic cracking mechanisms, catalytic reactors, and biofuel properties. We also discuss future prospects for direct thermochemical conversion in biorefineries for the production of high grade biofuels.
Efficient evaluation of crop phenotypes is a prerequisite for breeding, cultivar adoption, genomics and phenomics study. Plant genotyping is developing rapidly through the use of high-throughput sequencing techniques, while plant phenotyping has lagged far behind and it has become the rate-limiting factor in genetics, large-scale breeding and development of new cultivars. In this paper, we consider crop phenotyping technology under three categories. The first is high-throughput phenotyping techniques in controlled environments such as greenhouses or specifically designed platforms. The second is a phenotypic strengthening test in semi-controlled environments, especially for traits that are difficult to be tested in multi-environment trials (MET), such as lodging, drought and disease resistance. The third is MET in uncontrolled environments, in which crop plants are managed according to farmer’s cultural practices. Research and application of these phenotyping techniques are reviewed and methods for MET improvement proposed.
Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.
To adapt to the trend toward low-energy precision irrigation, the droplet distributions for two new prototype sprinklers, outside signal sprinkler (OS) and fluidic sprinkler (FS), were compared with impact sprinkler (IS). A laser precipitation monitor was used to measure the droplet distributions. Droplet size and velocity distributions were tested under four operating pressures for nozzles 1.5 m above the ground. For the operating pressures tested, the mean OS, FS and IS droplet diameters ranged from 0 to 3.4, 0 to 3.5, 0 to 4.0 mm, respectively. The mean OS and FS droplet velocities ranged from 0 to 6.3 m·s-1, whereas IS ranged from 0 to 6.3 m·s-1. Being gas-liquid fluidic sprinklers, droplet distributions of the OS and FS were similar, although not identical. IS mostly produced a 0.5 mm larger droplet diameter and a 0.5 m·s-1 greater velocity than OS and FS. A new empirical equation is proposed for determination of droplet size for OS and FS, which is sufficiently accurate and simple to use. Basic statistics for droplet size and velocity were performed on data obtained by the photographic methods. The mean droplet diameter (arithmetic, volumetric and median) decreased and the mean velocity increased in operating pressure for the three types of sprinkler.
Novel Poncirus trifoliata simple sequence repeat (SSR) markers were developed to evaluate their utility for genetic diversity and breeding studies of P. trifoliata and related species. A total of 108 primer pairs were characterized by PCR amplification experiments. Among these, 61 were polymorphic and transferable to other citrus species. The number of alleles per locus ranged from 2 to 6, with an average of 2.37 alleles per locus. The expected heterozygosity and observed heterozygosity ranged from 0 to 0.83 and 0 to 1.00, respectively. These novel polymorphic SSR markers will be useful for citrus cultivar identification and evaluation as well as breeding studies.
The Neospora caninum immune mapped protein 1 (NcIMP1) was identified as a membrane protein, and a previous study indicated that NcIMP1 could be a promising vaccine candidate against neosporosis. In this study, the immune response and protection efficacy of NcIMP1 were evaluated. The coding sequence of NcIMP1 was inserted into the eukaryotic expression vector pcDNA 3.1(+), resulting in the recombination plasmid pcDNA-IMP1, which was used for the intramuscular immunization of BALB/c mice. After immunization, the immune response was evaluated using a lymphoproliferative assay and cytokine and antibody measurements. Quantification of the cerebral parasite burden of mice challenged with 2 × 106N. caninum was performed 14 days after the last immunization. The results showed that the mice immunized with pcDNA-IMP1 developed a high level of specific antibody responses against recombinant NcIMP1, with a mixed IgG1/IgG2a response and a predominance of IgG2a production. The cellular immune response was associated with the production of IFN-γ, IL-2, IL-4 and IL-10 cytokines. The experiment was terminated 30 days p.i., and the cerebral parasite burden in each mouse was assessed by quantitative PCR. The parasite burden was significantly reduced in the pcDNA-IMP1-vaccinated mice. These data suggest that IMP1 is a promising vaccine candidate against neosporosis.
Suppressor of cytokine signaling 1 (SOCS1) protein can inhibit the signal transduction triggered by some cytokines or hormones and thus are important in many physiological/pathological processes, including innate and adaptive immunity, inflammation, and development in mammals. However, there is sparse information about their structure, tissue expression, in birds, where their biological functions remain unknown. In this study, we cloned and characterized two SOCS1 genes (named cSOCS1a and cSOCS1b) from chickens. SOCS1a is predicted to encode a 207-amino acid protein, which shares high amino acid sequence identity (64%–67%) with human and mouse SOCS1. Besides SOCS1a, a novel SOCS1b gene was also identified in chickens and other non-mammalian vertebrates including Xenopus tropicalis. Chicken SOCS1b is predicted to encode a 212-amino acid protein, which shares only 30%–32% amino acid sequence identity with human SOCS1 and cSOCS1a. RT-PCR assay revealed that both cSOCS1a and cSOCS1b are widely expressed in all chicken tissues. Using a luciferase reporter assay system, we further demonstrated that transient expression of cSOCS1a and cSOCS1b can significantly inhibit chicken growth hormone (GH)- or prolactin (PRL)-induced luciferase activities of Hep G2 cells expressing cGH receptor (or cPRL receptor), indicating that SOCS1a and SOCS1b proteins can negatively regulate GH/PRL signaling. Taken together, these data suggest that both cSOCS1a and cSOCS1b may function as negative regulators of cytokine/hormone actions, such as modulation of GH/PRL actions in chickens.
Several reliable methods to produce transgenic animals use the male genome. After penetration into oocytes, sperm DNA undergoes dramatic conformational changes that might represent an opportunity for exogenous DNA to integrate into the zygote genome. A nuclease, DNase I, with Ca2+/Mg2+ dependent activity and Zn2+ inhibition, is one of the enzymes responsible for sperm DNA remodeling. To date, the effect of different calcium concentrations in manipulation media on porcine intracytoplasmic sperm injection has not been fully investigated. The present study was conducted to examine the effect of calcium in the surrounding media, and we found that the number of embryos expressing green fluorescent protein (EGFP) was increased in media containing Ca2+. However, the number did not change over Ca2+ concentrations from 2 to 8 mmol·L–1 (P>0.05). Moreover, free Ca2+ concentrations in the media were found to affect the efficiency which is ICSI embryos expressing EGFP protein, which was related to the activation of ooplasmic DNase I. These findings reveal a mechanism and pathway involving EGFP expression in ICSI embryos.
Myostatin is a transforming growth factor-β family member that normally acts to limit skeletal muscle growth. Myostatin gene (MSTN) knockout (KO) mice show possible effects for the prevention or treatment of metabolic disorders such as obesity and type 2 diabetes. We applied chromatography and mass spectrometry based metabonomics to assess system-wide metabolic response of heterozygous MSTN KO (MSTN+/-) swine. Most of the metabolic data for MSTN+/- swine were similar to the data for wild type (WT) control swine. There were, however, metabolic changes related to fatty acid metabolism, glucose utilization, lipid metabolism, as well as BCAA catabolism caused by monoallelic MSTN depletion.The statistical analyses suggested that: (1) most metabolic changes were not significant in MSTN+/- swine compared to WT swine; (2) only a few metabolic properties were significantly different between KO and WT swine, especially for lipid metabolism. Significantly, these minor changes were most evident in female KO swine and suggested differences in gender sensitivity to myostatin.