Improving the ecological efficiency of farmland use (EEFU) has become an important part of ensuring food security and solving environmental pollution problems. At present, the Chinese government is actively promoting large-scale farmland transfer to reduce the level of farmer-/plot-scale farmland fragmentation (FF), so it is crucial to clarify the effect of landscape-scale FF on EEFU. This study applies the non-dynamic panel and threshold models in an empirical study of the municipal administrative regions along the Yangtze River Economic Belt (2000, 2005, 2010, and 2015).
View Article and Find Full Text PDFThe periplasmic protein SurA is the primary chaperone involved in the biogenesis of bacterial outer membrane proteins and is a potential antibacterial drug target. The three-dimensional structure of SurA can be divided into three parts, a core module formed by the N- and C-terminal regions and two peptidyl-prolyl isomerase (PPIase) domains, P1 and P2. Despite the determination of the structures of several SurA-peptide complexes, the functional mechanism of this chaperone remains elusive and the roles of the two PPIase domains are yet unclear.
View Article and Find Full Text PDFEvolution of enzymes plays a crucial role in obtaining new biological functions for all life forms. Arsenate reductases (ArsC) are several families of arsenic detoxification enzymes that reduce arsenate to arsenite, which can subsequently be extruded from cells by specific transporters. Among these, the Synechocystis ArsC (SynArsC) is structurally homologous to the well characterized thioredoxin (Trx)-coupled ArsC family but requires the glutaredoxin (Grx) system for its reactivation, therefore classified as a unique Trx/Grx-hybrid family.
View Article and Find Full Text PDFBreeding of excellent rice varieties is essential for modern rice production. Typical breeding procedures to introduce and maintain valuable agricultural traits require at least 8 generations from crossing to stabilization, always taking more than 4-5 years of work. This long and tedious process is the rate-limiting step in the development of new varieties, and therefore fast culturing methods are in urgent need.
View Article and Find Full Text PDFThe inflammasome is a key component of the innate immune system providing the initial defense against invading organisms. Failure of inflammasome formation is the main reason for many innate and acquired immune diseases. Cytosolic protein absent in melanoma 2 (AIM2) has been reported to play an essential role in double-stranded DNA (dsDNA) sensing and inflammasome formation in response to viruses or bacteria infection.
View Article and Find Full Text PDFFlavin monooxygenases (FMOs) play critical roles in plant growth and development by synthesizing auxin and other signaling molecules. However, the structure and function relationship within plant FMOs is not understood. Here we defined the important residues and domains of the Arabidopsis YUC1 FMO, a key enzyme in auxin biosynthesis.
View Article and Find Full Text PDFMap-based cloning has been widely used to identify genes responsible for mutant phenotypes in Arabidopsis, especially those mutants generated by EMS or fast neutron mutagenesis. The success of map-based cloning relies on the availability of molecular markers that distinguish the polymorphisms between two Arabidopsis ecotypes. So far, most molecular markers in Arabidopsis have been generated by individual laboratories or the Arabidopsis Information Resource (TAIR).
View Article and Find Full Text PDFPlant hormones are small organic molecules that influence almost every aspect of plant growth and development. Genetic and molecular studies have revealed a large number of genes that are involved in responses to numerous plant hormones, including auxin, gibberellin, cytokinin, abscisic acid, ethylene, jasmonic acid, salicylic acid, and brassinosteroid. Here, we develop an Arabidopsis hormone database, which aims to provide a systematic and comprehensive view of genes participating in plant hormonal regulation, as well as morphological phenotypes controlled by plant hormones.
View Article and Find Full Text PDF* Auxin is essential for many aspects of plant growth and development, including the determination of lateral organ shapes. * Here, the characterization of a dominant Arabidopsis thaliana mutant spl-D (SPOROCYTELESS dominant), and the roles of SPL in auxin homeostasis and plant development, are reported. * The spl-D mutant displayed a severe up-curling leaf phenotype caused by increased expression of SPOROCYTELESS/NOZZLE (SPL/NZZ), a putative transcription factor gene that was previously linked to sporocyte formation.
View Article and Find Full Text PDFWe previously reported that Arabidopsis indole-3-acetic acid (IAA)-methyltransferase-1 (IAMT1) catalyzes the conversion of IAA, an essential phytohormone, to methyl-IAA (MeIAA) and that IAMT1 plays an important role in leaf development. Here, we present the possible mechanisms of action of MeIAA in Arabidopsis. We showed that MeIAA was more potent than IAA in the inhibition of hypocotyl elongation and that MeIAA and naphthalene-acetic acid (NAA), but not IAA, rescued the hypocotyl gravitropic defects in dark-grown aux1.
View Article and Find Full Text PDFPollen germination on the surface of compatible stigmatic tissues is an essential step for plant fertilization. Here we report that the Arabidopsis mutant bcl1 is male sterile as a result of the failure of pollen germination. We show that the bcl1 mutant allele cannot be transmitted by male gametophytes and no homozygous bcl1 mutants were obtained.
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