SiteFinding-PCR: a simple and efficient PCR method for chromosome walking

In this paper, we present a novel PCR method, termed SiteFinding-PCR, for gene or chromosome walking. The PCR was primed by a SiteFinder at a low temperature, and then the target molecules were amplified exponentially with gene-specific and SiteFinder primers, and screened out by another gene-specific primer and a vector primer. However, non-target molecules could not be amplified exponentially owing to the suppression effect of stem–loop structure and could not be screened out. This simple method proved to be efficient, reliable, inexpensive and time-saving, and may be suitable for the molecules for which gene-specific primers are available. More importantly, large DNA fragments can be obtained easily using this method. To demonstrate the feasibility and efficiency of SiteFinding-PCR, we employed this method to do chromosome walking and obtained 16 positive results from 17 samples

Tuber indicum and T. lijiangense colonization differentially regulates plant physiological responses and mycorrhizosphere bacterial community of Castanopsis rockii seedlings

Black truffles and white truffles are widely studied around the world, but their effects on plant growth and physiological responses, and on the mycorrhizosphere bacterial community of the host plant remain unclear. Here, mycorrhizal colonization of Castanopsis rockii by Tuber indicum (Chinese black truffle) and T. lijiangense (Chinese white truffle), respectively, was induced in a greenhouse study, and their effects on host growth, physiological responses and mycorrhizosphere bacterial communities were compared. The results show that colonization of both Tuber species significantly increased leaf photosynthetic rate, leaf P concentration and mycorrhizosphere acid phosphatase activity, as well as richness of mycorrhizosphere bacterial communities of C. rockii seedlings. However, T. indicum colonization on the one hand significantly decreased tartrate content, bacterial acid phosphatase, phoC gene abundance in the mycorrhizosphere, and peroxidase (POD) activity of ectomycorrhizal root tips, but on the other hand increased mycorrhizosphere pH and superoxide dismutase (SOD) of ectomycorrhizal root tips, compared to T. lijiangense colonization. Moreover, principal coordinate and β-diversity analyses show significant differences in mycorrhizosphere bacterial community composition between T. indicum and T. lijiangese colonized C. rockii seedlings. Finally, the relative abundance of the bacterium Agromyces cerinus significantly correlated to mycorrhizosphere acid phosphatase activity and leaf P concentration, suggesting that this bacterium might play an important role in P mobilization and acquisition. Overall, these results suggest that T. indicum and T. lijiangense differently regulate their host plant’s physiological responses and mycorrhizosphere bacterial community

Suckling Piglet Intestinal Enterocyte Nutrient Metabolism Changes

Background/Aims: Intestinal morphology and the types of enterocytes are changed in piglets during the suckling period, but it is unclear whether these changes are associated with metabolic changes in epithelium. The present study was conducted to test the hypothesis that glucose, fatty acids, and amino acid metabolism in differentiated piglet enterocytes changed during suckling. Methods: Twenty-four piglets (Duroc × [Landrace × Yorkshire]) from 8 litters (3 piglets/litter) were selected. A single piglet from each litter was randomly selected and euthanized at days 7, 14, and 21. Differentiated enterocytes (DE) were isolated from their mid-jejunum. Isobaric tags for relative and absolute quantification and subsequent liquid chromatography-tandem mass spectrometry were used to identify and measure protein synthesis. Results: The results showed that various activities, including: cellular processes; metabolic processes; biological regulation; pigmentation; and, localization, in DEs changed during suckling. Metabolic process analyses revealed that protein expression related to glycolysis and citrate cycle was decreased from day 7 to day 14. The number of differentiated enterocytes of 21 d piglets increased compared to 7 d piglets. Most of the proteins involved in fatty acid and amino acids metabolism had decreased DE expression between day 7 and day 14. Some, but not all, detected proteins down-regulated in DEs of 21 day piglets compared to 7 day piglets. Conclusion: These results indicate that glucose, fatty acids, and amino acids metabolism changed during suckling. This may provide useful information for designing feed formulas and regulating piglet intestinal growth and development

The LSD1-Type Zinc Finger Motifs of Pisum sativa LSD1 Are a Novel Nuclear Localization Signal and Interact with Importin Alpha

Background: Genetic studies of the Arabidopsis mutant lsd1 highlight the important role of LSD1 in the negative regulation of plant programmed cell death (PCD). Arabidopsis thaliana LSD1 (AtLSD1) contains three LSD1-type zinc finger motifs, which are involved in the protein-protein interaction. Methodology/Principal Findings: To further understand the function of LSD1, we have analyzed cellular localization and functional localization domains of Pisum sativa LSD1 (PsLSD1), which is a homolog of AtLSD1. Subcellular localization analysis of green fluorescent protein (GFP)-tagged PsLSD1 indicates that PsLSD1 is localized in the nucleus. Using a series of GFP-tagged PsLSD1 deletion mutants, we found that the three LSD1-type zinc finger motifs of PsLSD1 alone can target GFP to the nucleus, whereas deletion of the three zinc finger motifs or any individual zinc finger motif causes PsLSD1 to lose its nuclear localization, indicating that the three zinc finger motifs are necessary and sufficient for its nuclear localization. Moreover, site-directed mutagenesis analysis of GFP-tagged PsLSD1 indicates that tertiary structure and basic amino acids of each zinc finger motif are necessary for PsLSD1 nuclear localization. In addition, yeast two-hybrid, pull-down, and BiFC assays demonstrate that the three zinc finger motifs of PsLSD1 directly bind to importin alpha in vitro and in vivo. Conclusions/Significance: Our data demonstrate that the LSD1-type zinc finger motifs of PsLSD1 are a novel nuclear localization signal and directly bind to importin alpha, and suggest that the nuclear import of LSD1 may rely on the interaction between its zinc finger motifs and importin alpha. Moreover, the nuclear localization of PsLSD1 suggests that LSD1 may function as a transcription regulator involved in negatively regulating PCD.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000292929500042&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Multidisciplinary SciencesSCI(E)PubMed11ARTICLE7e22131

The LSD1-Interacting Protein GILP Is a LITAF Domain Protein That Negatively Regulates Hypersensitive Cell Death in Arabidopsis

Hypersensitive cell death, a form of avirulent pathogen-induced programmed cell death (PCD), is one of the most efficient plant innate immunity. However, its regulatory mechanism is poorly understood. AtLSD1 is an important negative regulator of PCD and only two proteins, AtbZIP10 and AtMC1, have been reported to interact with AtLSD1.To identify a novel regulator of hypersensitive cell death, we investigate the possible role of plant LITAF domain protein GILP in hypersensitive cell death. Subcellular localization analysis showed that AtGILP is localized in the plasma membrane and its plasma membrane localization is dependent on its LITAF domain. Yeast two-hybrid and pull-down assays demonstrated that AtGILP interacts with AtLSD1. Pull-down assays showed that both the N-terminal and the C-terminal domains of AtGILP are sufficient for interactions with AtLSD1 and that the N-terminal domain of AtLSD1 is involved in the interaction with AtGILP. Real-time PCR analysis showed that AtGILP expression is up-regulated by the avirulent pathogen Pseudomonas syringae pv. tomato DC3000 avrRpt2 (Pst avrRpt2) and fumonisin B1 (FB1) that trigger PCD. Compared with wild-type plants, transgenic plants overexpressing AtGILP exhibited significantly less cell death when inoculated with Pst avrRpt2, indicating that AtGILP negatively regulates hypersensitive cell death.These results suggest that the LITAF domain protein AtGILP localizes in the plasma membrane, interacts with AtLSD1, and is involved in negatively regulating PCD. We propose that AtGILP functions as a membrane anchor, bringing other regulators of PCD, such as AtLSD1, to the plasma membrane. Human LITAF domain protein may be involved in the regulation of PCD, suggesting the evolutionarily conserved function of LITAF domain proteins in the regulation of PCD

The Characteristics of Highly Cited Researchers in China

Highly cited researchers are a small group of scientists who have made outstanding contributions to pioneering the frontier, creating knowledge for society, and reform and innovation. To some extent, highly cited researchers reflect the commanding height of a country's talents. We analyze the characteristics of Chinese researchers who have been selected for at least three years in the list of highly cited researchers from 2014 to 2019. The study found that there are obvious gender differences among Chinese highly cited researchers 95% of them are male. About 80% of the highly cited researchers come from “985” project universities and Chinese Academy of Sciences institute. Moreover, most Chinese HCRs are researchers with multidisciplinary backgrounds, and most of them come from the natural sciences. More than half of the top scientists (53.94%) were selected as highly cited researchers for the first time during the development period of their careers. The results also shown that Chinese highly cited researchers have produced the most academic papers in the mature period and the first six years of the recession period. When recruiting talents, institutions can focus on the people in the development or mature period, which can bring the maximum benefits to the institutions quickly

The Central Role of mTORC1 in Amino Acid Sensing

Abstract The mTOR is a master regulator of cell growth that controls cell homeostasis in response to nutrients, growth factors, and other environmental cues. Recent studies have emphasized the importance of lysosomes as a hub for nutrient sensing, especially amino acid sensing by mTORC1. This review highlights recent advances in understanding the amino acid–mTORC1 signaling axis and the role of mTORC1 in cancer.</jats:p

Pyrimidine Biosynthetic Enzyme CAD: Its Function, Regulation, and Diagnostic Potential

CAD (Carbamoyl-phosphate synthetase 2, Aspartate transcarbamoylase, and Dihydroorotase) is a multifunctional protein that participates in the initial three speed-limiting steps of pyrimidine nucleotide synthesis. Over the past two decades, extensive investigations have been conducted to unmask CAD as a central player for the synthesis of nucleic acids, active intermediates, and cell membranes. Meanwhile, the important role of CAD in various physiopathological processes has also been emphasized. Deregulation of CAD-related pathways or CAD mutations cause cancer, neurological disorders, and inherited metabolic diseases. Here, we review the structure, function, and regulation of CAD in mammalian physiology as well as human diseases, and provide insights into the potential to target CAD in future clinical applications.</jats:p