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Carbonate stress has profound impacts on both agricultural and industrial production. Although a number of salinity-tolerant genes have been reported and applied in plants, there is a lack of research on the role of cell wall-related genes in resistance to carbonate. Likewise, in industry, current strategies have not been able to more effectively address the conflict between stress-induced microalgal biofuel accumulation and microalgal growth inhibition. It is of great significance to study the adaptation mechanism of carbonate-tolerant organisms and to explore related genes for future genetic modification. In this study, the role of the cell wall in the NaHCO3-tolerant chlorella JB17 was investigated. We found that JB17 possesses a relatively thick cell wall with a thickness of 300–600 nm, which is much higher than that of the control chlorella with a thickness of about 100 nm. Determination of the cell wall polysaccharide fractions showed that the cellulose content in the JB17 cell wall increased by 10.48% after NaHCO3 treatment, and the decrease in cellulose levels by cellulase digestion inhibited its resistance to NaHCO3. Moreover, the saccharide metabolome revealed that glucose, rhamnose, and trehalose levels were higher in JB17, especially rhamnose and trehalose, which were almost 40 times higher than in control chlorella. Gene expression detection identified an up-regulated expressed gene after NaHCO3 treatment, JbKOBITO1, overexpression of which could improve the NaHCO3 tolerance of Chlamydomonas reinhardtii. As it encodes a glycosyltransferase-like protein that is involved in cellulose synthesis, the strong tolerance of JB17 to NaHCO3 may be partly due to the up-regulated expression of JbKOBITO 1 and JbKOBITO 1-mediated cellulose accumulation. The above results revealed a critical role of cellulose in the NaHCO3 resistance of JB17, and the identified NaHCO3-tolerance gene will provide genetic resources for crop breeding in saline-alkali soils and for genetic modification of microalgae for biofuel production.

Metabolism plays an important role in regulating aging at several levels, and metabolic reprogramming is the main driving force of aging. Due to the different metabolic needs of different tissues, the change trend of metabolites during aging in different organs and the influence of different levels of metabolites on organ function are also different, which makes the relationship between the change of metabolite level and aging more complex. However, not all of these changes lead to aging. The development of metabonomics research has opened a door for people to understand the overall changes in the metabolic level in the aging process of organisms. The omics-based “aging clock” of organisms has been established at the level of gene, protein and epigenetic modifications, but there is still no systematic summary at the level of metabolism. Here, we reviewed the relevant research published in the last decade on aging and organ metabolomic changes, discussed several metabolites with high repetition rate, and explained their role in vivo, hoping to find a group of metabolites that can be used as metabolic markers of aging. This information should provide valuable information for future diagnosis or clinical intervention of aging and age-related diseases.

Sodium bicarbonate (NaHCO3) is an important inorganic salt. It is not only widely used in industrial production and daily life, but is also the main stress in alkaline saline soil. NaHCO3 has a strong ability to inhibit the growth of fungi in both natural environment and daily application. However, the mechanism by which fungi respond to NaHCO3 stress is not fully understood. To further clarify the toxic mechanisms of NaHCO3 stress and identify the specific cellular genes and pathways involved in NaHCO3 resistance, we performed genome-wide screening with NaHCO3 using a Saccharomyces cerevisiae deletion mutant library. A total of 33 deletion mutants with NaHCO3 sensitivity were identified. Compared with wild-type strains, these mutants had significant growth defects in the medium containing NaHCO3. Bioinformatics analysis found that the corresponding genes of these mutants are mainly enriched in the cell cycle, mitophagy, cell wall integrity, and signaling pathways. Further study using transcriptomic analysis showed that 309 upregulated and 233 downregulated genes were only responded to NaHCO3 stress, when compared with yeast transcriptomic data under alkaline and saline stress. Upregulated genes were mainly concentrated in amino acid metabolism, steroid biosynthesis, and cell wall, while downregulated genes were enriched in various cellular metabolisms. In summary, we have identified the cellular pathways and key genes that respond to NaHCO3 stress in the whole genome, providing resource and direction for understanding NaHCO3 toxicity and cellular resistance mechanisms.

Stress granules (SGs) are highly dynamic cytoplasmic foci formed in response to stress. The formation of SGs is reported to be regulated by diverse post-translational protein modifications (PTMs). Among them, ADP-ribosylation is of emerging interest due to its recently identified roles in SG organization. In this review, we summarized the latest advances on the roles of poly(ADP-ribose) (PAR) in the regulation of SG formation and dynamics, including its function in modulating nucleocytoplasmic trafficking and SG recruitment of SG components, as well as its effects on protein phase separation behavior. Moreover, the functional role of PAR chain diversity on dynamic of SG composition is also introduced. Potential future developments on investigating global ADP-ribosylation networks, individual roles of different PARPs, and interactions between ADP-ribosylation and other PTMs in SGs are also discussed.

Positive-sense (+) RNA viruses represent the most abundant group of viruses and are dependent on the host cell machinery to replicate. One remarkable feature that occurs after (+) RNA virus entry into cells is the remodeling of host endomembranes, leading to the formation of viral replication factories. Recently, rapid progress in three-dimensional (3D) imaging technologies, such as electron tomography (ET) and focused ion beam-scanning electron microscopy (FIB-SEM), has enabled researchers to visualize the novel membrane structures induced by viruses at high resolution. These 3D imaging technologies provide new mechanistic insights into the viral infection cycle. In this review, we summarize the latest reports on the cellular remodeling that occurs during plant virus infection; in particular, we focus on studies that provide 3D architectural information on viral replication factories. We also outline the mechanisms underlying the formation of these membranous structures and discuss possible future research directions.

Carbonate stress has profound impacts on both agricultural and industrial production. Although a number of salinity-tolerant genes have been reported and applied in plants, there is a lack of research on the role of cell wall-related genes in resistance to carbonate. Likewise, in industry, current strategies have not been able to more effectively address the conflict between stress-induced microalgal biofuel accumulation and microalgal growth inhibition. It is of great significance to study the adaptation mechanism of carbonate-tolerant organisms and to explore related genes for future genetic modification. In this study, the role of the cell wall in the NaHCO3-tolerant chlorella JB17 was investigated. We found that JB17 possesses a relatively thick cell wall with a thickness of 300-600 nm, which is much higher than that of the control chlorella with a thickness of about 100 nm. Determination of the cell wall polysaccharide fractions showed that the cellulose content in the JB17 cell wall increased by 10.48% after NaHCO3 treatment, and the decrease in cellulose levels by cellulase digestion inhibited its resistance to NaHCO3. Moreover, the saccharide metabolome revealed that glucose, rhamnose, and trehalose levels were higher in JB17, especially rhamnose and trehalose, which were almost 40 times higher than in control chlorella. Gene expression detection identified an up-regulated expressed gene after NaHCO3 treatment, JbKOBITO1, overexpression of which could improve the NaHCO3 tolerance of Chlamydomonas reinhardtii. As it encodes a glycosyltransferase-like protein that is involved in cellulose synthesis, the strong tolerance of JB17 to NaHCO3 may be partly due to the up-regulated expression of JbKOBITO 1 and JbKOBITO 1-mediated cellulose accumulation. The above results revealed a critical role of cellulose in the NaHCO3 resistance of JB17, and the identified NaHCO3-tolerance gene will provide genetic resources for crop breeding in saline-alkali soils and for genetic modification of microalgae for biofuel production. [ABSTRACT FROM AUTHOR]