Distributions of surface sediments surrounding the Antarctic Peninsula and its environmental significance

We analyzed grain size composition to provide information on the types and distributions as well as depositional varieties of marine surface sediments from the area surrounding the Antarctic Peninsula. The samples retrieved from the study area contain gravel, sand, silt and clay. As suggested by bathymetry and morphology, the study area is characterized by neritic, hemipelagic and pelagic deposits. The glacial-marine sediments can be divided into two types, residual paratill and compound paratill, which are primarily transported by glaciers and as ice-rafted debris. Ocean current effects on deposition are more obvious, and the deposit types are distributed consistently with terrain variations

ARPN Journal of Agricultural and Biological Science MULTIPLE COPIES OF THE ACTIVATOR INTERACT WITH A HETEROLOGOUS PROMOTER TO REGULATE GENE EXPRESSION

ABSTRACT To extend our knowledge of gene expression regulated by multiple copies of the same activator, a chimeric promoter was constructed, which contained five copies of the ocs activator (-294 to -116 relative to the transcription start site) added upstream of the same truncated mas promoter (-189 to +65 relative to the transcription start site). The chimeric promoter was linked to a β-glucuronidase reporter gene and introduced into tobacco plants. The results of the fluorometric assays exhibit that addition of five copies of the ocs activator to the mas promoter increases the level of GUS activity 3.5-fold in leaves but 3.3-fold in roots, respectively. This indicates that affixing multiple copies of the same element can produce higher gene expression. Further study has shown that multimerization of the ocs activator also influences wound inducibility of the chimeric promoter

Applications of Nanobodies in Mycotoxin Detection

Mycotoxins, as secondary metabolites produced by fungi, are a common threat to food safety and are hazardous to human and livestock health. Mycotoxin contamination of agricultural products causes significant economic losses worldwide. Therefore, it is particularly urgent to develop technologies for mycotoxins detection, degradation, and controlling their contamination. Immunoassays, which use antibodies, are now commonly used for the detection and largescale screening of mycotoxins in agricultural products. As a new type of antibody, nanobodies have a small size, easy expression in vitro, and high stability compared to traditional monoclonal and polyclonal antibodies. Therefore, they are widely used in mycotoxin detection technologies. In this review, we summarize the development of nanobodies for common mycotoxins (aflatoxin, ochratoxin, fumonisin, zearalenone, deoxynivalenol, etc.) detection, focus on the applications of antim ycotoxin and anti-idiotypic nanobodies in the context of several immunoassay methods, mainly compare the detecti on parameters such as half inhibition rate, detection limit, and linear range. We further describe the advantages and disadvantages of detection technologies based on anti-mycotoxin and anti-idiotypic nanobodies and discuss the key issues in the development of mycotoxin detection methods, such as the difficulty of developing new nanobodies and the small number of detectable mycotoxins when using current methods. Moreover, we point out the future directions of applying rational design, directed evolution, and peptide screen and design methods to develop nanobody variants and propose potential avenues for the future development of nanobody-based mycotoxin detection technologies

Progress in Protein Interactomics Technologies and Their Applications to Plants Research

Protein interactomics is a cutting-edge technology to identify and quantify the interaction of proteins with other metabolites or molecules like proteins, which has been an important part of plant systems biology and multi-omics research. In recent years, the rapid development of mass spectrometry-based omics technologies has facilitated great progress in methodologies for discovery and verification of the protein-metabolite interaction (PMI) and protein-protein interaction (PPI), which are the main protein interactomic technologies, showing great potential for applications in plant functional genomic and metabolomic studies gradually. Here, we present a systematic overview of the analysis strategies of different protein interactomics technologies (including PMI and PPI) in the past decade and analyze their advantages, disadvantages and specific applicable interaction types. The application progress and application strategies of protein interactomics technologies in plant research and the key technical bottlenecks that need to be overcome are also summarized. In the near future, the continuous development of interactomics technologies will further leverage the analysis of intracellular signal transduction and metabolic regulatory pathways in plants, and precise analysis of key interactions in signal networks will provide important information for the studies of the growth and development of plants and their adaptation to external environment

Research Progess in the Evolution and Functions of Plant α-galactosidases

α-galactosidase (α-gal, EC 3.2.1.22) is a kind of exoglycosidase that can specifically catalyze the hydrolysis ofα-galactoside bonds. It has the ability to hydrolyze theα-1, 6-galactoside bonds involved in galacto-oligosaccharides such as melibiose, raffinose, and stachyose, galactomannans, galactolipids and glycoproteins. It has widely been found in animals, plants and microorganisms (archaea, bacteria, fungi) and etc. As its catalytic specificity, α-Gal has been widely used in such fields as food, feed, agriculture, medicine and light industry, and it is considered as one of the most promising enzyme preparations.α-Gal from different species and families exhibit great differences in sequence homology, advanced catalytic structure, catalytic active site, enzyme-substrate binding mechanism, and thermal stability etc., which greatly limits the development and application ofα-Gal. Compared with studies onα-Gal in microorganisms, studies onα-Gal in plants are still relatively limited. In plants, α-Gal is widely involved in important physiological processes such as leaf development and senescence, seed development and germination, fruit softening and ripening and stress response. However, the physiological and molecular mechanisms ofα-Gal involved in these processes mentioned above have still been unclear. Therefore, based on the previous researches and reports onα-Gal, the origin, distribution, classification, catalytic property and applications, GH protein family evolution ofα-Gal and its biological functions on the biosynthesis, transport, unloading and catabolism of RFO, seed development, dehydration tolerance and germination, response to high and/or low temperature, salt and other abiotic stresses, and cell wall remodeling in plants are mainly reviewed in this paper