AGC protein kinase AGC1-4 mediates seed size in Arabidopsis.

KEY MESSAGE: AGC1-4 kinase plays a crucial role in the regulation of seeds by mediating cell proliferation and embryo development in Arabidopsis. Seed size is a crucial factor to influence final seed yield in plants. However, the molecular mechanisms that set final seed size still need to be investigated. Here, we identified a novel AGC protein kinase AGC1-4, which encodes a serine-threonine kinase, belongs to the AGC VIIIa subfamily. The seeds of agc1-4 mutant were significantly larger than that in the wild type. Overexpression of the AGC1-4 gene reduced seed size. Regulation of AGC1-4 seed size is dependent on embryonic cell number. To further determine AGC1-4 functions in seed size, we analyzed AGC1-4 phosphoproteins using label-free quantitative phosphoproteomics coupled to the transcriptome of agc1-4 using RNA sequencing (RNA-seq). The RNA-seq analysis showed 1611 differentially expressed genes (DEGs), which cover a wide range of functions, such as cell cycle and embryo development. The 262 unique phosphoproteins were detected by phosphoproteomics analysis. The differentially phosphorylated proteins were involved in cell cycle and post-embryo development. Overlay of the RNA-seq and phosphoproteomics results demonstrated AGC1-4 as an important factor that influences seed size by mediating cell proliferation and embryo development. The results in this study provide novel data on the serine-threonine kinase AGC1-4 mediating seed size in Arabidopsis.

Characterization, antioxidant and antiinflammation of mycelia selenium polysaccharides from Hypsizygus marmoreus SK-03.

The synergistical action of inflammation response with oxidative stress has been reported to be response for the pathogenesis of lipopolysaccharide (LPS)-induced lung damage. In our present work, the antioxidative and anti-inflammatory efficacies of mycelia selenium polysaccharides (MSPS) from Hypsizigus marmoreus SK-03 in LPS-induced lung damaged mice, and its structure characterizations had been evaluated and analyzed. The animal investigations indicated that MSPS markedly ameliorated pulmonary injuries by the regulations of related inflammatory events via the observably antioxidant effects at the dose of 800 mg/kg. The characterizations showed that MSPS was a α- and ß-configurational semi-crystalline polymer with small molecular weights, and expressed an integrated surface and regular shapes with homogeneous particles. Taken together, the current work demonstrated that MSPS might be a potentially effective candidate medicine for the treatment of lung damage and its complications.

Characterization and Attenuation of Streptozotocin-Induced Diabetic Organ Damage by Polysaccharides from Spent Mushroom Substrate (Pleurotus eryngii).

The aim of this work was to characterize spent mushroom substrate polysaccharides (MSP) from Pleurotus eryngii and their antioxidant and organ protective effects in streptozotocin- (STZ-) induced diabetic mice. The enzymatic-, acidic-, and alkalic- (En-, Ac-, and Al-) MSP were extracted from P. eryngii with snailase (4%), hydrochloric acid (1 mol/l), and sodium hydroxide (1 mol/l), respectively. The characterizations were evaluated by spectral analysis. In animal experiments, the enzymatic activities, lipid peroxide contents, and serum lipid parameters were measured, and histological observations of the liver, kidney, pancreas, and heart were conducted. The results demonstrated that treatment with En-, Ac-, and Al-MSP increased the organ enzymatic activities, decreased the organ lipid peroxide contents, mitigated the serum biochemistry values, and ameliorated the histopathology of diabetic mice, indicating that En-, Ac-, and Al-MSP could potentially be used as functional foods for the prevention of diabetes.