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• Drought responses were measured for grass species on loamy and sandy soils. • Sandy soil is beneficial for plant growth but harmful for plant drought resistance. • Fibrous-rooted species might provide a buffer against drought in loamy soil. • Degraded grasslands with coarser soil might be more sensitive to drought. Grassland degradation is often accompanied by coarsened soil, which could change water and nutrient uptake by plant roots. Studying the effects of soil coarsening on species performance with different root systems under manipulated irrigation has important practical significance in grassland restoration under changing climate. We conducted a common garden experiment with three water treatments (control, drought stressed and water addition) and two soil texture (loamy soil which is fine and sandy soil which is coarse) under a rainout shelter to explore the effects of degradation on the growth and drought response of tap-rooted species and fibrous-rooted species. Three fibrous-rooted species (Setaira viridis , Cleistogenes squarrosa and Leymus chinensis) and three tap-rooted species (Medicago ruthenica , Artemisia frigida and Potentilla bifurca) were used in the study (P. bifurca failed to germinate). The results showed that three of the five selected species tended to have higher aboveground biomass, greater belowground biomass, larger height and longer root length in sandy soil than in loamy soil. For fibrous-rooted species, drought had negative influence on several plant traits in sandy soil, and had no influence on plant traits in loamy soil. For tap-rooted species, drought had negative influence on plant traits both in loamy soil and in sandy soil, and the influence was larger in loamy soil than in sandy soil. The results showed that loamy soil might provide a buffer against drought for fibrous-rooted species, but make tap-rooted species more sensitive to drought. Our results implied that degraded grasslands with coarsened soil might change community composition in the grassland, making tap-rooted species take the place of fibrous-rooted species. Thus, soil coarsening is an important factor in predicting drought resistance as well as composition of the community, and should be given more attention under future climate changes. [ABSTRACT FROM AUTHOR]

• Common garden experiments were conducted for 3 steppe species and 2 soils in China. • Plant traits shift obviously from early to late stage across the growing season. • H N distinguishes specie adaptability difference on degraded and nondegraded soils. • Artimisia frigida shows greater nitrogen stoichiometric homeostasis for shoot and root on degraded soil. • Our results explain the resistance of prevailing Artemisia frigida- steppe in China. The degraded grassland is characterized by changes in dominant species and decreased soil resource supply capacity, limiting community foraging by carbon capturing and/or resource absorption. In this study, we used a manipulative greenhouse experiment to explore the plant trait variations of three species representing three degradation succession stages in the Inner Mongolian grassland of China. We examined variability in key trait values during early, middle and late growing stages and assessed the nitrogen stoichiometric homeostasis (H N) of different plant organs growing on loamy (undegraded) and sandy (degraded) soils. The results showed that plant root length (RL) shifted significantly from the early to middle stage, where Artemisia frigida presented the longest RL, and Setaria viridis had the shortest RL. Leyums chinensis exhibited the largest root-shoot ratio (RSR) with a well-developed rhizome, while A. frigida had smaller but variable RSR which increased 1.57–2.15 times, changing from the resource acquisition to the resource conservation strategy from the early to late stage. The shoot nitrogen content (SNC) and root nitrogen content (RNC) decreased over the growing season. No obvious differences were observed between plant traits of L. chinensis or A. frigida when growing on loamy or sandy soils, despite the fact that the nutrient supply in loamy soil was better. Shoot H N showed higher values for plants growing on loamy soils than on sandy soils. The degradation indicator species A. frigida presented the highest shoot H N under sandy soil and held relatively stable root H N for both soils (6.71 vs 6.00), indicating a higher adaptability to sandy soils. Our results explained the occurrence of the stable degraded grassland dominated by A. frigida and could shed light on methods for its restoration. [ABSTRACT FROM AUTHOR]

Evolutionarily conserved SCAN (named after SRE-ZBP, CTfin51, AW-1, and Number 18 cDNA)-domain-containing zinc finger transcription factors (ZSCAN) have been found in both mouse and human genomes. Zscan4 is transiently expressed during zygotic genome activation (ZGA) in preimplantation embryos and induced pluripotent stem cell (iPSC) reprogramming. However, little is known about the mechanism of Zscan4 underlying these processes of cell fate control. Here, we show that Zscan4f, a representative of ZSCAN proteins, is able to recruit Tet2 through its SCAN domain. The Zscan4f-Tet2 interaction promotes DNA demethylation and regulates the expression of target genes, particularly those encoding glycolytic enzymes and proteasome subunits. Zscan4f regulates metabolic rewiring, enhances proteasome function, and ultimately promotes iPSC generation. These results identify Zscan4f as an important partner of Tet2 in regulating target genes and promoting iPSC generation and suggest a possible and common mechanism shared by SCAN family transcription factors to recruit ten-eleven translocation (TET) DNA dioxygenases to regulate diverse cellular processes, including reprogramming. • Zscan4f is a sequence-specific DNA-binding transcription factor • Zscan4f, a representative of ZSCAN proteins, is a functional partner for Tet2 • The ZSCAN4-TET2 complex regulates metabolic rewiring and activates proteasome activity • Recruiting TET may represent a general biochemical mechanism of ZSCAN proteins Cheng et al. show that Zscan4f recruits Tet2 to target gene promoters, promotes DNA demethylation, regulates metabolic rewiring, and activates proteasome activity, indicating a mechanism of Zscan4 to control cell fate. This study also uncovers a potential and common biochemical mechanism shared by the SCAN family to recruit TET enzymes. [ABSTRACT FROM AUTHOR]