Different contributions of plant diversity and soil properties to the community stability in the arid desert ecosystem.

As a one of the focuses of ecological research, understanding the regulation of plant diversity on community stability is helpful to reveal the adaption of plant to environmental changes. However, the relationship between plant diversity and community stability is still controversial due to the scale effect of its influencing factors. In this study, we compared the changes in community stability and different plant diversity (i.e., species, functional, and phylogenetic diversities) between three communities (i.e., riparian forest, ecotone community, and desert shrubs), and across three spatial scales (i.e., 100, 400, and 2500 m2), and then quantified the contribution of soil properties and plant diversity to community stability by using structural equation model (SEM) in the Ebinur Lake Basin Nature Reserve of the Xinjiang Uygur Autonomous Region in the NW China. The results showed that: (1) community stability differed among three communities (ecotone community > desert shrubs > riparian forest). The stability of three communities all decreased with the increase of spatial scale (2) species diversity, phylogenetic richness and the mean pairwise phylogenetic distance were higher in ecotone community than that in desert shrubs and riparian forest, while the mean nearest taxa distance showed as riparian forest > ecotone community > desert shrubs. (3) Soil ammonium nitrogen and total phosphorus had the significant direct negative and positive effects on the community stability, respectively. Soil ammonium nitrogen and total phosphorus also indirectly affected community stability by adjusting plant diversity. The interaction among species, functional and phylogenetic diversities also regulated the variation of community stability across the spatial scales. Our results suggested that the effect of plant diversities on community stability were greater than that of soil factors. The asynchronous effect caused by the changes in species composition and functional traits among communities had a positive impact on the stability. Our study provided a theoretical support for the conservation and management of biodiversity and community functions in desert areas.

LncRNA SAMD12-AS1 Promotes the Progression of Gastric Cancer via DNMT1/p53 Axis.

BACKGROUND: Long noncoding RNAs (lncRNAs) are essential modulators of cancers initiation and progression via regulating gene expression and biological behaviors. LncRNA SAMD12-AS1 has been validated to promote the progression of several cancers, while its role in gastric cancer (GC) remains unclear. This study aims to explore the role of LncRNA SAMD12-AS1 in GC. METHODS: qRT-PCR was performed to analyze the expression of lncRNA SAMD12-AS1 in GC tissues and cell lines, with Kaplan-Meier curve analyzing the correlation between LncRNA SAMD12-AS1 and prognosis. CCK-8 assay, and flow cytometry were applied to detect GC cells proliferation, cell cycle. Binding of RNA and proteins were detected via RNA binding protein immunoprecipitation (RIP) assay. Protein levels of oncogenesis-related genes were determined via western blotting. RESULTS: SAMD12-AS1 was highly up-regulated in human gastric cancer tissues and cell lines compared to their normal counterparts. High SAMD12-AS1 expression was closely related to TNM stage, and shorter survival span of patients with GC. Moreover, SAMD12-AS1 was also found to promote the oncogenic role of GC cells via inhibiting the P53 signaling pathway. Mechanistically, SAMD12-AS1 might performed its biological roles in GC via directly interacting with DNMT1 and facilitating DNMT1 repress the P53 signaling pathway. CONCLUSION: Our study demonstrated that SAMD12-AS1 promoted GC progression via DNMT1/P53 axis, indicating SAMD12-AS1 may be envisioned as a novel biomarker of, and therapeutic target for GC.

High Air Humidity Causes Atmospheric Water Absorption via Assimilating Branches in the Deep-Rooted Tree Haloxylon ammodendron in an Arid Desert Region of Northwest China.

Atmospheric water is one of the main water resources for plants in arid ecosystems. However, whether deep-rooted, tomentum-less desert trees can absorb atmospheric water via aerial organs and transport the water into their bodies remains poorly understood. In the present study, a woody, deep-rooted, tomentum-less plant, Haloxylon ammodendron (C.A. Mey.) Bunge, was selected as the experimental object to investigate the preconditions for and consequences of foliar water uptake. Plant water status, gas exchange, and 18O isotopic signatures of the plant were investigated following a typical rainfall pulse and a high-humidity exposure experiment. The results showed that a high content of atmospheric water was the prerequisite for foliar water uptake by H. ammodendron in the arid desert region. After atmospheric water was absorbed via the assimilating branches, which perform the function of leaves due to leaf degeneration, the plant transported the water to the secondary branches and trunk stems, but not to the taproot xylem or the soil, based on the 18O isotopic signatures of the specimen. Foliar water uptake altered the plant water status and gas exchange-related traits, i.e., water potential, stomatal conductance, transpiration rate, and instantaneous water use efficiency. Our results suggest that atmospheric water might be a subsidiary water resource for sustaining the survival and growth of deep-rooted plants in arid desert regions. These findings contribute to the knowledge of plant water physiology and restoration of desert plants in the arid regions of the planet.