Identification and Analysis of the MIR399 Gene Family in Grapevine Reveal Their Potential Functions in Abiotic Stress

MiR399 plays an important role in plant growth and development. The objective of the present study was to elucidate the evolutionary characteristics of the MIR399 gene family in grapevine and investigate its role in stress response. To comprehensively investigate the functions of miR399 in grapevine, nine members of the Vvi-MIR399 family were identified based on the genome, using a miRBase database search, located on four chromosomes (Chr 2, Chr 10, Chr 15, and Chr 16). The lengths of the Vvi-miR399 precursor sequences ranged from 82 to 122 nt and they formed stable stem-loop structures, indicating that they could produce microRNAs (miRNAs). Furthermore, our results suggested that the 2 to 20 nt region of miR399 mature sequences were relatively conserved among family members. Phylogenetic analysis revealed that the Vvi-MIR399 members of dicots (Arabidopsis, tomato, and sweet orange) and monocots (rice and grapevine) could be divided into three clades, and most of the Vvi-MIR399s were closely related to sweet orange in dicots. Promoter analysis of Vvi-MIR399s showed that the majority of the predicted cis-elements were related to stress response. A total of 66.7% (6/9) of the Vvi-MIR399 promoters harbored drought, GA, and SA response elements, and 44.4% (4/9) of the Vvi-MIRR399 promoters also presented elements involved in ABA and MeJA response. The expression trend of Vvi-MIR399s was consistent in different tissues, with the lowest expression level in mature and young fruits and the highest expression level in stems and young leaves. However, nine Vvi-MIR399s and four target genes showed different expression patterns when exposed to low light, high light, heat, cold, drought, and salt stress. Interestingly, a putative target of Vvi-MIR399 targeted multiple genes; for example, seven Vvi-MIR399s simultaneously targeted VIT_213s0067g03280.1. Furthermore, overexpression of Vvi_MIR399e and Vvi_MIR399f in Arabidopsis enhanced tolerance to drought compared with wild-type (WT). In contrast, the survival rate of Vvi_MIR399d-overexpressed plants were zero after drought stress. In conclusion, Vvi-MIR399e and Vvi-MIR399f, which are related to drought tolerance in grapevine, provide candidate genes for future drought resistance breeding.

More Robust Co-Occurrence Patterns and Stronger Dispersal Limitations of Bacterial Communities in Wet than Dry Seasons of Riparian Wetlands

Riparian wetlands can be used as "sentinels" of environmental changes and play pivotal roles in ecological and biogeochemical processes. The bacterial community is an essential and rapidly responding component in riparian areas. However, the co-occurrence patterns and phylogenetic group-based ecological processes during wet-dry periods are still open questions. Here, we compared the co-occurrence patterns and phylogenetic group-based assembly mechanisms of soil bacterial communities in typical riparian wetlands across wet and dry seasons, which are subjected to intensive agricultural activities. The results showed that the potential functions, community composition, network structure, and phylogenetic group-based ecological processes of the bacterial community were distinct between the wet and dry seasons. The stability and complexity of the wet season bacterial network were significantly higher than those of the dry season bacterial network. Moreover, the phylogenetic group-based null model analysis showed that homogeneous selection (HoS), dispersal limitation (DL), and drift (DR) were the most important ecological processes for the bacterial community assemblages, with a higher proportion of DL in the wet season (36.7%) than in the dry season (25.5%) but lower contributions of the HoS (36.1% versus 41.3%) and DR (20.8% versus 25.4%). The communities dominated by Flavobacteriales, Burkholderiales, and Sphingomonadales in the wet season were controlled more by dispersal limitation, whereas they were significantly negatively correlated with precipitation, dissolved organic carbon, and total carbon in the dry season, respectively. These findings expand our understanding of the network vulnerability and assembly mechanisms in fragile anthropologically affected riparian wetland ecosystems. IMPORTANCE Riparian wetlands comprise microbial communities that are easily affected by the surrounding conditions, especially in agricultural landscapes with a wide range of ecosystem services. After comparing the wet and dry season microbiota, we found that the soil bacterial community of the wet season exhibited a higher complexity and stability of soil bacterial network and stronger dispersal limitations than that of the dry season; however, the dry season bacteria showed stronger homogeneous selection than the wet season bacteria. The co-occurrence and phylogenetic group-based bacterial community assembly mechanisms were mainly shaped by the divergence in temperature and precipitation between seasons. Revealing the variations in the potential functions, co-occurrence, and community assembly processes between wet and dry seasons is critical to understanding the maintenance of soil microbial diversity in riparian wetlands with regard to environmental sceneries.

Analysis of Microbiota Structure and Potential Functions Influencing Spoilage of Fresh Beef Meat

Beef is one of the most consumed food worldwide, and it is prone to spoilage by bacteria. This risk could be caused by resident microbiota and their alterations in fresh beef meat during processing. However, scarce information is available regarding potential spoilage factors due to resident microbiota in fresh beef meat. In this study, we analyzed the microbiota composition and their predicted functions on fresh beef meat. A total of 120 beef meat samples (60 fresh ground and 60 non-ground beef samples) were collected from three different sites in South Korea on different months, and the microbiota were analyzed by the MiSeq system. Our results showed that although the microbiota in beef meat were varied among sampling site and months, the dominant phyla were the same with shared core bacteria. Notably, psychrotrophic genera, related to spoilage, were detected in all samples, and their prevalence increased significantly in July. These genera could inhibit the growth of other microbes with using glucose by fermentation. The results of this study extend our understanding of initial microbiota in fresh beef meat and potential functions influencing spoilage and can be useful to develop the preventive measures to reduce the spoilage of beef meat products.

Two types of potential functions and their use in the modeling of information: two applications from the social sciences

In this paper we consider how two types of potential functions, the real and quantum potential can be shown to be of use in a social science context. The real potential function is a key ingredient in the Hamiltonian framework used in both classical and quantum mechanics. The quantum potential however emerges in a different way in quantum mechanics. In this paper we consider both potentials and we attempt to give them a social science interpretation within the setting of two applications.