Angiotensin II type 2 receptor as a novel activator of brown adipose tissue in obesity

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Angiotensin II type 2 receptor as a novel activator of brown adipose tissue in obesity

Angiotensin II type 2 receptor as a noval activator of brown adipose tissue in obesity.


Abstract

The angiotensin II type 2 receptor (AT2R) exerts vasorelaxant, anti-inflammatory, and antioxidant properties. In obesity, its activation counterbalances the adverse cardiovascular effects of angiotensin II mediated by the AT1R. Preliminary results indicate that it also promotes brown adipocyte differentiation in vitro. Our hypothesis is that AT2R activation could increase BAT mass and activity in obesity. Five-week-old male C57BL/6J mice were fed a standard or a high-fat (HF) diet for 6 weeks. Half of the animals were treated with compound 21 (C21), a selective AT2R agonist, (1 mg/kg/day) in the drinking water. Electron transport chain (ETC), oxidative phosphorylation, and UCP1 proteins were measured in the interscapular BAT (iBAT) and thoracic perivascular adipose tissue (tPVAT) as well as inflammatory and oxidative parameters. Differentiation and oxygen consumption rate (OCR) in the presence of C21 was tested in brown preadipocytes. In vitro, C21-differentiated brown adipocytes showed an AT2R-dependent increase of differentiation markers (Ucp1, Cidea, Pparg) and increased basal and H+ leak-linked OCR. In vivo, HF-C21 mice showed increased iBAT mass compared to HF animals. Both their iBAT and tPVAT showed higher protein levels of the ETC protein complexes and UCP1, together with a reduction of inflammatory and oxidative markers. The activation of the AT2R increases BAT mass, mitochondrial activity, and reduces markers of tissue inflammation and oxidative stress in obesity. Therefore, insulin reduction and better vascular responses are achieved. Thus, the activation of the protective arm of the renin–angiotensin system arises as a promising tool in the treatment of obesity.

Genomic approaches to enhance adaptive plasticity to cope with soil constraints amidst climate change in wheat

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Abstract

Climate change is varying the availability of resources, soil physicochemical properties, and rainfall events, which collectively determines soil physical and chemical properties. Soil constraints—acidity (pH < 6), salinity (pH ≤ 8.5), sodicity, and dispersion (pH > 8.5)—are major causes of wheat yield loss in arid and semiarid cropping systems. To cope with changing environments, plants employ adaptive strategies such as phenotypic plasticity, a key multifaceted trait, to promote shifts in phenotypes. Adaptive strategies for constrained soils are complex, determined by key functional traits and genotype × environment × management interactions. The understanding of the molecular basis of stress tolerance is particularly challenging for plasticity traits. Advances in sequencing and high-throughput genomics technologies have identified functional alleles in gene-rich regions, haplotypes, candidate genes, mechanisms, and in silico gene expression profiles at various growth developmental stages. Our review focuses on favorable alleles for enhanced gene expression, quantitative trait loci, and epigenetic regulation of plant responses to soil constraints, including heavy metal stress and nutrient limitations. A strategy is then described for quantitative traits in wheat by investigating significant alleles and functional characterization of variants, followed by gene validation using advanced genomic tools, and marker development for molecular breeding and genome editing. Moreover, the review highlights the progress of gene editing in wheat, multiplex gene editing, and novel alleles for smart control of gene expression. Application of these advanced genomic technologies to enhance plasticity traits along with soil management practices will be an effective tool to build yield, stability, and sustainability on constrained soils in the face of climate change.

Breeding evaluation and precise mapping of Fhb8 for Fusarium head blight resistance in wheat (Triticum aestivum)

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Abstract

The percentage of Fusarium-damaged kernels (FDK) was proposed as a type of Fusarium head blight (FHB) resistance displayed in matured wheat kernels. In this study, Qfdk.nau-7D, a QTL identified in the Wangshuibai genome for its association with FDK, was introduced into FHB-susceptible common wheat line PH691 through marker-assisted selection and backcrossing. Evaluation of two resulted near-isogenic lines (NILs) showed that the contribution of Qfdk.nau-7D interval to lower FDK resulted from its effects on resistance to pathogen infection and to disease spread within the spike. Of a few major agronomic traits evaluated, head length was the only one that made difference between PH691 and the NILs. To reduce the QTL interval, a high-density marker map was constructed using a BC3F2 population of 97 plants. Through resistance evaluation of the homozygous recombinant lines in repeated field trials, Qfdk.nau-7D, designated as Fhb8, was placed in a 1.0-cM Xwgrb1500-Xwgrb1559 interval (from 93.9–96.5 Mb in CS) and showed co-segregation with Xwgrb1587. Moreover, it was found that the association of Fhb8 with head length was due to close linkage with spike length QTL HL2.

Breeding of Lotus japonicus that can overcome adverse seasonal environment by coupling flowering time and abiotic stresses

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Abstract

Manipulation of floral transition may allow for a free change in the duration of plant vegetative and reproductive growth, thus rendering them to avoid adverse seasonal environmental conditions. In this report, we investigated the effect of the stress-inducible promoter RD29A on driving the rice FT ortholog Hd3a expression in Lotus japonicus ‘MG20’ in response to environmental changes. Constitutive overexpression of Hd3a (HOE) in ‘MG20’ hastened its flowering in contrast to non-transformed control (wild type; WT), which did not flower in winter hampered by long days and low temperatures. RD29A promoter had low activity under non-stress conditions and was induced by cold, drought and salinity in transgenic ‘MG20’. Transgenic plants of Hd3a driven by the RD29A promoter (RH) could flower under unfavourable weather conditions that prohibited the flowering of WT plants. In addition, RH transgenic plants exhibited thriving clumps of branching, inflorescence, and pods because of the low temperature-induced expression of Hd3a. These results demonstrate that inducible expression of florigen has the potential to tackle unfavourable weather conditions and boost plant production.

Progress and prospect of developing salt and alkali tolerant rice using hybrid rice technology in China

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Abstract

Soil salinization and alkalization are important abiotic stresses that affect crop growth and yield. Development of salt and alkali tolerant varieties is still dominated by the following conventional breeding method: The salt and alkali tolerant traits from screened germplasm are introduced into elite varieties by means of hybridization and backcrossing. In recent years, the breeding of salt and alkali tolerant rice has also made great progress. For example, the yield of Chao-You 1000, a two-line rice hybrid, has reached 12.04 t/ha growing in fields with salinity between 0.2% and 0.6%. This review is an update on the progress of salt and alkali tolerant rice germplasm screening and new salt and alkali tolerant varieties in development. By reviewing the performance of current rice hybrids in China's National Regional Variety Trials of Saline-Alkali Tolerant Rice, we proposed the technical approach of developing saline–alkali tolerant rice hybrids using the third-generation hybrid rice technology and furthermore the trend of developing salt and alkali tolerant rice hybrids.