Hemeroby is an integrated indicator used to measure the impact and degree of all human interventions on ecological components or ecosystems. The constant exploitation of resources is a strong interference of human beings to the natural environment. With the depletion of non-renewable resources, some cities with resource exploitation as their main industry—“resource-based cities”—are facing great development pressure. In order to quantify the impact of human disturbance on the natural environment and provide some scientific support for policy makers of the resource-based city, we used remote sensing images and landscape pattern metrics, introduced the synthetic hemeroby index model and analyzed the relationship between human disturbance and landscape pattern during 1990–2017. The results showed that: (1) The hemeroby in Daqing continued to rise during 1990–2017, and the main factor was the continuous expansion of the construction land and the reclamation of farmland. (2) In the areas with different hemeroby, there were significant differences in landscape pattern. In the areas with high-level hemeroby, the heterogeneity of landscape pattern was low, the aggregation among patches was high, and the shape of patches was regular, whereas the landscape pattern in the areas with medium-level hemeroby was just opposite. Although the heterogeneity of landscape pattern and the aggregation among patches were high in the areas with low-level hemeroby, the complexity of landscape was low and the shape of patches was regular. (3) In the temporal dimension, the increase of hemeroby contributed to the complexity of patch shape, the decrease of the aggregation among patches, and the fragmentation of landscape pattern. In the spatial dimension, the response in landscape pattern to human disturbance was relatively insensitive in the areas with low-level hemeroby, and this response was basically same in the high-level hemeroby and the whole study areas.

Arabidopsis (Arabidopsis thaliana) UNFERTILIZED EMBRYO SAC 12 (AtUNE12) belongs to the basic helix–loop–helix DNA-binding superfamily of proteins. However, its function is not well known. Here, we found that AtUNE12 plays an important role in mediating salt tolerance. AtUNE12 is a transcriptional activator located in the nucleus whose expression is induced by NaCl, mannitol, and abscisic acid. In addition to binding to the G-box “CACGTG”, AtUNE12 also binds to the low temperature responsive element 15 (LTRE15) “CCGAC”. Furthermore, the serine residue at position 108 of AtUNE12 is phosphorylated during the salt stress response, enabling AtUNE12 to trigger gene expression by binding to G-box and/or LTRE15 motifs. Phosphorylated AtUNE12 regulates the expression of the genes involved in ion transport leading to reduced Na+ accumulation and K+ loss. At the same time, phosphorylation of AtUNE12 also induces the expression of AtMYB61 to decrease stomatal aperture, leading to a reduced transpiration rate. Overall, AtUNE12 serves as a transcriptional activator that is induced and phosphorylated upon salt stress, and the induction and phosphorylation of AtUNE12 in turn activate the salt-overly-sensitive pathway and decrease the stomatal aperture, enabling improved salt tolerance.

DNA-protein interaction is one of the most crucial interactions in biological processes. However, the technologies available to study DNA-protein interactions are all based on DNA hybridization; however, DNA hybridization is not highly specific and is relatively low in efficiency. RNA-guided DNA recognition is highly specific and efficient. To overcome the limitations of technologies based on DNA hybridization, we built a DNA-binding protein capture technology based on the clustered regularly interspaced palindromic repeats (CRISPR)-dead Cas9 (dCas9) system and transient genetic transformation, termed reverse chromatin immunoprecipitation based on CRISPR-dCas9 system (R-ChIP-dCas9). In this system, dCas9 was fused with Strep-Tag II to form a fusion protein for StrepTactin affinity purification. Transient transformation was performed for the expression of dCas9 and gRNA to form the dCas9-gRNA complex in birch (Betula platyphylla) plants, which binds to the target genomic DNA region. The dCas9-gRNA-DNA complex was crosslinked, then the chromatin was sonicated into fragments, and purified using StrepTactin beads. The proteins binding to the target genomic DNA region were identified using mass spectrometry. Using this method, we determined the upstream regulators of a NAM, ATAF and CUC (NAC) transcription factor, BpNAC090, and 32 transcription factors potentially regulating BpNAC090 were identified. The reliability of R-ChIP-dCas9 was further confirmed by chromatin immunoprecipitation (ChIP), electrophoretic mobility shifty assays (EMSA) and yeast one-hybrid (Y1H). This technology can be adapted to various plant species and does not depend on the availability of a stable transformation system; therefore, it has wide application in identifying proteins bound to genomic DNA.

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<abstract> <p>On the basis of logistic models of forest restoration, we consider the influence of population pressure on forest restoration and establish a reaction diffusion model with Holling Ⅱ functional responses. We study this reaction diffusion model under Dirichlet boundary conditions and obtain a positive equilibrium. In the square region, we analyze the existence of Turing instability and Hopf bifurcation near this point. The square patterns and mixed patterns are obtained when steady-state bifurcation occurs, the hyperhexagonal patterns appears in Hopf bifurcation.</p> </abstract>