Myosins are encoded by multigene families and are involved in many basic biological processes. However, their functions in plants remain poorly understood. Here, we report the functional characterization of maize (Zea mays) opaque1 (o1), which encodes a myosin XI protein. o1 is a classic maize seed mutant with an opaque endosperm phenotype but a normal zein protein content. Compared with the wild type, o1 endosperm cells display dilated endoplasmic reticulum (ER) structures and an increased number of smaller, misshapen protein bodies. The O1 gene was isolated by map-based cloning and was shown to encode a member of the plant myosin XI family (myosin XI-I). In endosperm cells, the O1 protein is associated with rough ER and protein bodies. Overexpression of the O1 tail domain (the C-terminal 644 amino acids) significantly inhibited ER streaming in tobacco (Nicotiana benthamiana) cells. Yeast two-hybrid analysis suggested an association between O1 and the ER through a heat shock protein 70-interacting protein. In summary, this study indicated that O1 influences protein body biogenesis by affecting ER morphology and motility, ultimately affecting endosperm texture.

Switching the macromolecular helicity of poly­(phenylacetylene)­s (PPAs) through external achiral stimuli provides convenient possibilities in designing smart chiral materials. Herein, a series of PPAs carrying dendritic oligoethylene glycol (OEG) pendants were synthesized with different linkages between the backbone and dendron pendants, including benzamide (PPA-AC), inverted acylamide (PPA-AM), diamide (PPA-dAM), benzoate (PPA-ES), and benzyl ester (PPA-OEG). The periphery of the OEG dendrons is capped with either an ethoxy (PPA-ACe) or a methoxy group (PPA-ACm) to afford the PPAs with different overall hydrophilicity. These dendronized PPAs inherit unprecedented thermoresponsiveness from the dendritic OEGs and show characteristic thermally induced phase transitions with cloud points (T cps) in the range 30–54 °C. Hydrogen bonding interactions between neighboring repeating units were found to play a key role in transferring chirality from pendants to polymer backbone. Dependent on the linkages, these PPAs behave differently about helix–helix transitions driven by the thermally induced collapse of the pendanted OEG dendrons. Interestingly, dendronized homopolymer with methoxy terminals (PPA-ACm) shows radial amphiphilicity in aqueous solutions, which renders the polymer a different chiroptical property. For comparison, chiroptical properties of these polymers were also investigated in organic solvents. Furthermore, coordination with Ba2+ was found to mediate the chiroptical properties of these dendronized PPAs in aqueous solutions, which can be surprisingly shielded by OEG dendrons below their T cps.

Objective. Previous studies have shown that some metabolic risk factors are related to nonalcoholic fatty liver disease (NAFLD). This retrospective study was performed to investigate the associations between physical examinations and blood biochemistry parameters and NAFLD status and to identify possible risk factors of NAFLD. Methods. Study participants underwent general physical examinations, blood biochemistry, and abdominal ultrasound evaluations. In addition, data regarding sex, age, ethnicity, medical history, and alcohol consumption of participants were recorded. Among the study participants (N=1994), 57.8% were male, 41.2% over the age of 50, and 52.6% with BMI≥24. 986 patients had NAFLD and 1008 had no NAFLD. We used effect size analysis and logistic regression to determine which physical examinations and blood biochemistry parameters were significant for the association between these parameters and NAFLD status. Results. Both the effect size and logistic regression indicated that BMI, diastolic blood pressure (DBP), triglycerides (TG), and serum uric acid (SUA) show a significant association with NAFLD. Females are overall at a higher risk of NAFLD, but factors such as high BMI, DBP, TG, and SUA increase the associated risk for both sexes. Compared with males, females have a higher risk of NAFLD given that they are over 50, overweight and obese (BMI at or over 24), or have high SUA. In terms of age, people older than 50 with high SUA, and people younger than 50 with high DBP and low-density lipoprotein cholesterol (LDL-C) all increase the risk of NAFLD. For BMI, high DBP and low high-density lipoprotein cholesterol (HDL-C) are risk factors for NAFLD in overweight and obese people (BMI at or over 24), whereas in normal weight and underweight people (BMI under 24), elevated LDL-C increases the risk of NAFLD. Conclusions. Our results revealed sex, age, and BMI modulate the association of physical examinations and blood biochemistry parameters and NAFLD, which may facilitate the development of personalized early warning and prevention strategies of NAFLD for at-risk populations.

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