Seafood intake in childhood/adolescence and the risk of obesity: results from a Nationwide Cohort Study.

BACKGROUND & AIMS: Obesity has been linked to various detrimental health consequences. While there is established evidence of a negative correlation between seafood consumption and obesity in adults, the current research on the association between seafood intake in childhood/adolescence and the risk of obesity is lacking. Our aim was to evaluate the association between seafood intake in childhood/adolescence and the risk of obesity in a Chinese nationwide cohort. METHODS: We utilized data from the China Health and Nutrition Survey (CHNS) from the year of 1997 to 2015. Seafood consumption was evaluated through 3-day 24-hour recalls. In our study, overweight/obesity status was determined based on the Chinese Criteria of Overweight and Obesity in School-age Children and Adolescents (WS/T 586-2018), while abdominal obesity status was determined according to the Chinese Criteria of Waist Circumference Screening Threshold among Children and Adolescents (WS/T 611-2018). RESULTS: During an average follow-up of 7.9 years, 404 cases developed overweight/obesity among 2206 participants in the seafood-overweight/obesity analysis, while 381 cases developed abdominal obesity among 2256 participants in the seafood-abdominal-obesity analysis. The high-consumer group was associated with 35% lower risk of overweight/obesity risk and 26% lower risk of abdominal obesity after fully adjusting for sociodemographic and lifestyle factors, compared with the non-consumer group. Considering different cooking methods, boiled seafood consumption was associated with 43% lower risk of overweight/obesity and 23% lower risk of abdominal obesity in the fully adjusted model, while stir-fried seafood did not demonstrate a statistical significance. CONCLUSION: Higher intake of seafood in childhood/adolescents, particularly in a boiled way, was associated with lower obesity risk.

Identification of a c-type heme oxygenase and its function during acclimation of cyanobacteria to nitrogen fluctuations.

The mechanisms of acclimating to a nitrogen-fluctuating environment are necessary for the survival of aquatic cyanobacteria in their natural habitats, but our understanding is still far from complete. Here, the synthesis of phycobiliprotein is confirmed to be much earlier than that of photosystem components during recovery from nitrogen chlorosis and an unknown protein Ssr1698 is discovered to be involved in this synthetic process. The unknown protein is further identified as a c-type heme oxygenase (cHO) in tetrapyrrole biosynthetic pathway and catalyzes the opening of heme ring to form biliverdin IXα, which is required for phycobilin production and ensuing phycobiliprotein synthesis. In addition, the cHO-dependent phycobiliprotein is found to be vital for the growth of cyanobacterial cells during chlorosis and regreening through its nitrogen-storage and light-harvesting functions, respectively. Collectively, the cHO expressed preferentially during recovery from nitrogen chlorosis is identified in photosynthetic organisms and the dual function of this enzyme-dependent phycobiliprotein is proposed to be an important mechanism for acclimation of aquatic cyanobacteria to a nitrogen-fluctuating environment.

SlZHD17 is involved in the control of chlorophyll and carotenoid metabolism in tomato fruit.

Chlorophylls and carotenoids are essential and beneficial substances for both plant and human health. Identifying the regulatory network of these pigments is necessary for improving fruit quality. In a previous study, we identified an R2R3-MYB transcription factor, SlMYB72, that plays an important role in chlorophyll and carotenoid metabolism in tomato fruit. Here, we demonstrated that the SlMYB72-interacting protein SlZHD17, which belongs to the zinc-finger homeodomain transcription factor family, also functions in chlorophyll and carotenoid metabolism. Silencing SlZHD17 in tomato improved multiple beneficial agronomic traits, including dwarfism, accelerated flowering, and earlier fruit harvest. More importantly, downregulating SlZHD17 in fruits resulted in larger chloroplasts and a higher chlorophyll content. Dual-luciferase, yeast one-hybrid and electrophoretic mobility shift assays clarified that SlZHD17 regulates the chlorophyll biosynthesis gene SlPOR-B and chloroplast developmental regulator SlTKN2 in a direct manner. Chlorophyll degradation and plastid transformation were also retarded after suppression of SlZHD17 in fruits, which was caused by the inhibition of SlSGR1, a crucial factor in chlorophyll degradation. On the other hand, the expression of the carotenoid biosynthesis genes SlPSY1 and SlZISO was also suppressed and directly regulated by SlZHD17, which induced uneven pigmentation and decreased the lycopene content in fruits with SlZHD17 suppression at the ripe stage. Furthermore, the protein-protein interactions between SlZHD17 and other pigment regulators, including SlARF4, SlBEL11, and SlTAGL1, were also presented. This study provides new insight into the complex pigment regulatory network and provides new options for breeding strategies aiming to improve fruit quality.

BEL1-LIKE HOMEODOMAIN4 regulates chlorophyll accumulation, chloroplast development, and cell wall metabolism in tomato fruit.

Tomato (Solanum lycopersicum) is a model plant for studying fruit development and ripening. In this study, we found that down-regulation of a tomato bell-like homeodomain 4 (SlBL4) resulted in a slightly darker-green fruit phenotype and increased accumulation of starch, fructose, and glucose. Analysis of chlorophyll content and TEM observations was consistent with these phenotypes, indicating that SlBL4 was involved in chlorophyll accumulation and chloroplast formation. Ripened fruit of SlBL4-RNAi plants had noticeably decreased firmness, larger intercellular spaces, and thinner cell walls than the wild-type. RNA-seq identified differentially expressed genes involved in chlorophyll metabolism, chloroplast development, cell wall metabolism, and carotenoid metabolism. ChIP-seq identified (G/A) GCCCA (A/T/C) and (C/A/T) (C/A/T) AAAAA (G/A/T) (G/A) motifs. SlBL4 directly inhibited the expression of protoporphyrinogen oxidase (SlPPO), magnesium chelatase H subunit (SlCHLD), pectinesterase (SlPE), protochlorophyllide reductase (SlPOR), chlorophyll a/b binding protein 3B (SlCAB-3B), and homeobox protein knotted 2 (TKN2). In contrast, it positively regulated the expression of squamosa promoter binding protein-like colorless non-ripening (LeSPL-CNR). Our results indicate that SlBL4 is involved in chlorophyll accumulation, chloroplast development, cell wall metabolism, and the accumulation of carotenoids during tomato fruit ripening, and provide new insights for the transcriptional regulation mechanism of BELL-mediated fruit growth and ripening.

Superhydrophobic Coatings Prepared by the in Situ Growth of Silicone Nanofilaments on Alkali-Activated Geopolymers Surface.

As a highly hydrophobic and good environmental durable material, silicone nanofilaments have shown great advantages in the construction of superhydrophobic coatings. However, the synthesis of these materials has always been limited to the application of trifunctional organosilane monomers under the action of acidic catalysts. For the first time, long-chain polymeric hydrogenated siloxane-poly(methyl-hydrosiloxane) (PMHS) was used to synthesize rapidly silicone nanofilaments in situ under alkaline conditions. A dense silicone nanofilament coating was obtained by PMHS + geopolymer layer on a smooth iron sheet, and achieved by one-step brushing of PMHS on the surface of a just-solidified alkali-activated metakaolin-based geopolymer coating at 120 °C for an hour of sealed curing. This composite coating was followed by a superhydrophobic composite coating with a contact angle of approximately 161° and a rolling angle of 2°. Consistent with this, laser scanning confocal microscopy and field-emission scanning electron microscopy images show the presence of micro- and nanoscale features that enable the entrapment of air when exposed to water and endow excellent superhydrophobic properties. Because geopolymer material has good adhesion ability with metal, ceramic, or other materials, the composite superhydrophobic coating is expected to be widely used.

Overexpression of the KNOX gene Tkn4 affects pollen development and confers sensitivity to gibberellin and auxin in tomato.

The knotted1-like homeobox genes not only regulate the formation and differentiation of meristems and vascular system but are also involved in biosynthesis and signal transduction of diverse plant hormones in tomato. Here, we showed that a knotted1-like homeobox gene Tkn4 is required for pollen and pollen tube growth when this gene is overexpressed in tomato. Pollen grains in the Tkn4 overexpressed plants (Tkn4-OX) germinated quicker than those in the wild-type (WT) plant cultured in vitro in germination media. The percentage of fruit set was higher in Tkn4-OX than in WT plants and the transgenic plants showed an ordered inflorescence. Tkn4-OX seedlings also exhibited sensitivity to gibberellins (GA) and auxins. RNA sequencing results showed that the expression of genes related to sugar, cell wall-modification, microtubule-associated vesicular transport for pollen growth, GA and auxin synthesis were significantly changed. Hence, Tkn4 contributes to a function in the development of pollen and pollen tube and the regulation of phytohormones to participate in plant growth. These results provided a potential application value for agricultural improvement to enhance the rate of fruit set in tomato.