Adventitious roots (ARs) have an unmatched status in plant growth and metabolism due to the degeneration of primary roots in lotuses. In the present study, we sought to assess the effect of sucrose on ARs formation and observed that lignin synthesis was involved in ARs development. We found that the lignification degree of the ARs primordium was weaker in plants treated with 20 g/L sucrose than in 50 g/L sucrose treatment and control plants. The contents of lignin were lower in plants treated with 20 g/L sucrose and higher in plants treated with 50 g/L sucrose. The precursors of monomer lignin, including p-coumaric acid, caffeate, sinapinal aldehyde, and ferulic acid, were lower in the GL50 library than in the GL20 library. Further analysis revealed that the gene expression of these four metabolites had no novel difference in the GL50/GL20 libraries. However, a laccase17 gene (NnLAC17), involved in polymer lignin synthesis, had a higher expression in the GL50 library than in the GL20 library. Therefore, NnLAC17 was cloned and the overexpression of NnLAC17 was found to directly result in a decrease in the root number in transgenic Arabidopsis plants. These findings suggest that lignin synthesis is probably involved in ARs formation in lotus seedlings.

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Bacillus thuringiensis (Bt) transgenic cotton (Gossypium hirsutum L.) has been widely planted in Asia. However, efficacy of the Bt protein to kill pests has been inconsistent. Effects of gibberellic acid (GA3) and dimethylpiperidinium chloride (DPC) on boll Bt protein content were investigated on ‘Sikang1’ and ‘Siza3.’ Treatment of DPC increased the Bt protein contents in carpel wall and cotton seed at 10 d after flowering (DAF) and 30 DAF in 2014 and 2015. However, Bt protein contents of the GA3 treatment only at 30 DAF were higher for both cultivars in comparison to the control. To further investigate the mechanism, we found the ability of protein synthesis (indicated by enzyme activities of nitrate reductase [NR], glutamic‐pyruvic transaminase [GPT], and glutamic oxaloacetate transaminase [GOT], as well as contents of total nitrogen, free amino acid, and soluble protein) in bolls increased markedly with the application of DPC for both cultivars. Further analysis showed that there were positive linear correlations between Bt protein content and NR, GPT, and GOT activities and total nitrogen and soluble protein contents (r = 0.925∗∗, r = 0.691∗∗, r = 0.703∗∗, r = 0.682∗, r = 0.693∗∗, respectively) in carpel wall of bolls. Thus, DPC is potentially an effective chemical application to increase boll Bt protein content. Core Ideas Dimethylpiperidinium chloride (DPC) application can bolster boll insect resistance. Significant linear positive correlation between Bt protein content and ability of synthesis the protein was found in boll shell. DPC increases Bt protein content through increasing ability of synthesis the protein.

Genome size variation and hybridization occur frequently within or between plant species under diverse environmental conditions, which enrich species diversification and drive the evolutionary process. Elymus L. is the largest genus in Triticeae with five recognized basic genomes (St, H, P, W, and Y). However, the data on population cytogenetics of Elymus species are sparse, especially whether genome hybridization and chromosomal structure can be affected by altitude are still unknown. In order to explore the relationship between genome sizes, we studied interspecific hybridization and altitude of Elymus species at population genetic and cytological levels. Twenty-seven populations at nine different altitudes (2,800–4,300 m) of three Elymus species, namely, hexaploid E. nutans (StHY, 2n = 6x = 42), tetraploid E. burchan-buddae (StY, 2n = 4x = 28), and E. sibiricus (StH, 2n = 4x = 28), were sampled from the Qinghai–Tibetan Plateau (QTP) to estimate whether intraspecific variation could affect the genomic relationships by genomic in situ hybridization (GISH), and quantify the genome size of Elymus among different altitude ecological groups by flow cytometry. The genome size of E. nutans, E. burchan-buddae, and E. sibiricus varied from 12.38 to 22.33, 8.81 to 18.93, and 11.46 to 20.96 pg/2C with the averages of 19.59, 12.39, and 16.85 pg/2C, respectively. The curve regression analysis revealed a strong correlation between altitude and nuclear DNA content in three Elymus species. In addition, the chromosomes of the St and Y genomes demonstrated higher polymorphism than that of the H genome. Larger genome size variations occurred in the mid-altitude populations (3,900–4,300 m) compared with other-altitude populations, suggesting a notable altitudinal pattern in genome size variation, which shaped genome evolution by altitude. This result supports our former hypothesis that genetic richness center at medium altitude is useful and valuable for species adaptation to highland environmental conditions, germplasm utilization, and conservation.

Insulin resistance is recognized as one major feature of metabolic syndrome, and frequently emerges as a difficult problem encountered during long-term pharmacological treatment of diabetes. Insulin resistance often causes organs or tissues, such as skeletal muscle, adipose, and liver, to become less responsive or resistant to insulin. Exercise can promote the physiological function of those organs and tissues and benefits insulin action via increasing insulin receptor sensitivity, glucose uptake, and mitochondrial function. This is done by decreasing adipose tissue deposition, inflammatory cytokines, and oxidative stress. However, understanding the mechanism that regulates the interaction between exercise and insulin function becomes a challenging task. As a novel myokine, irisin is activated by exercise, released from the muscle, and affects multi-organ functions. Recent evidence indicates that it can promote glucose uptake, improve mitochondrial function, alleviate obesity, and decrease inflammation, as a result leading to the improvement of insulin action. We here will review the current evidence concerning the signaling pathways by which irisin regulates the effect of exercise on the up-regulation of insulin action in humans and animals.