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Semi‐arid alpine ecosystems on the Tibetan Plateau are experiencing rapid climate change and extensive anthropogenic activity, concomitant with the encroachment of shrubs. Shrub encroachment will lead to changes in both the ecosystem structure and functioning of the semi‐arid alpine steppes. Yet, the encroaching impacts of shrubs on the above‐ and belowground ecosystem functioning of the semi‐arid alpine steppes remain uncertain. To quantify shrub encroachment impacts on ecosystem functioning of the semi‐arid alpine steppes, two alpine steppe sites encroached by shrub species are investigated, with one site encroached by leguminous shrub species (Caragana spinifera) and another site encroached by non‐leguminous shrub species (Dasiphora fruticosa). Results shows that the individual ecosystem functions and the ecosystem multifunctionality (EMF) of alpine steppes are significantly enhanced following both leguminous and non‐leguminous shrubs encroachment. We conclude that shrub encroachment tends to facilitate the belowground EMF (BEMF) but has neutral effects on the aboveground EMF (AEMF) in alpine steppes. Our findings also highlight that soil nutrients play critical roles in driving ecosystem functioning responses to shrubs encroachment. These findings further our understanding of shrub encroachment impacts on the ecosystem functioning of the semi‐arid alpine steppes. [ABSTRACT FROM AUTHOR]

Paclitaxel (trade name Taxol) is a rare diterpenoid with anticancer activity isolated from Taxus. At present, paclitaxel is mainly produced by the semi-synthetic method using extract of Taxus tissues as raw materials. The studies of regulatory mechanisms in paclitaxel biosynthesis would promote the production of paclitaxel through tissue/cell culture approaches. Here, we systematically identified 990 transcription factors (TFs), 460 microRNAs (miRNAs), and 160 phased small interfering RNAs (phasiRNAs) in Taxus chinensis to explore their interactions and potential roles in regulation of paclitaxel synthesis. The expression levels of enzyme genes in cone and root were higher than those in leaf and bark. Nearly all enzyme genes in the paclitaxel synthesis pathway were significantly up-regulated after jasmonate treatment, except for GGPPS and CoA Ligase. The expression level of enzyme genes located in the latter steps of the synthesis pathway was significantly higher in female barks than in male. Regulatory TFs were inferred through co-expression network analysis, resulting in the identification of TFs from diverse families including MYB and AP2. Genes with ADP binding and copper ion binding functions were overrepresented in targets of miRNA genes. The miRNA targets were mainly enriched with genes in plant hormone signal transduction, mRNA surveillance pathway, cell cycle and DNA replication. Genes in oxidoreductase activity, protein-disulfide reductase activity were enriched in targets of phasiRNAs. Regulatory networks were further constructed including components of enzyme genes, TFs, miRNAs, and phasiRNAs. The hierarchical regulation of paclitaxel production by miRNAs and phasiRNAs indicates a robust regulation at post-transcriptional level. Our study on transcriptional and posttranscriptional regulation of paclitaxel synthesis provides clues for enhancing paclitaxel production using synthetic biology technology. [ABSTRACT FROM AUTHOR]

Lysine‐specific demethylase 1 (LSD1) is a flavin adenine dinucleotide (FAD) dependent monoamine oxidase (MAO) that erases the mono‐, and dimethylation of histone 3 lysine 4 (H3K4), resulting in the suppression of target gene transcriptions. Besides, it can also demethylate some nonhistone substrates to regulate their biological functions. As reported, LSD1 is widely upregulated and plays a key role in several kinds of cancers, pharmacological or genetic ablation of LSD1 in cancer cells suppresses cell aggressiveness by several distinct mechanisms. Therefore, numerous LSD1 inhibitors, including covalent and noncovalent, have been developed and several of them have entered clinical trials. Herein, we systemically reviewed and discussed the biological function of LSD1 in tumors, lymphocytes as well as LSD1‐targeting inhibitors in clinical trials, hoping to benefit the field of LSD1 and its inhibitors. [ABSTRACT FROM AUTHOR]