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311.
Food restriction (FR) is hypothesized to decrease body fat content of an animal and thus prevent obesity. However, the response
of energy budget to a continuous (CFR) or discontinuous FR (DFR) remains inconsistent. In the present study, effects of CFR
or DFR and refeeding on energy budget and behavior were examined in male Swiss mice. CFR significantly decreased the energy
expenditure associated with basal metabolic rate (BMR) and activity behavior, but not sufficiently to compensate for energy
deficit and thus resulted in lower body mass and fat content. DFR mice had a significantly higher food intake on ad libitum
days and showed increases in BMR and activity after 4 weeks’ DFR, which might resulted in lower body mass and less body fat
than controls. After being refed ad libitum, both CFR and DFR mice had similar body mass, BMR, and behavioral patterns to
controls but had 95% and 75% higher fat content. This suggested that not only CFR but also DFR would be a significant factor
in the process of obesity for animals that were refed ad libitum. It also indicated that food restriction interrupted many
times by periods of ad libitum feeding had the same long-term effects like continuous underfeeding. 相似文献
312.
Peiyu Liu Yan Liu Xiang Zhao Andrew P. Roberts Heng Zhang Yue Zheng Fuxian Wang Lushan Wang Nicolas Menguy Yongxin Pan Jinhua Li 《Environmental microbiology》2021,23(2):1115-1129
Magnetotactic bacteria (MTB) are diverse prokaryotes that produce magnetic nanocrystals within intracellular membranes (magnetosomes). Here, we present a large-scale analysis of diversity and magnetosome biomineralization in modern magnetotactic cocci, which are the most abundant MTB morphotypes in nature. Nineteen novel magnetotactic cocci species are identified phylogenetically and structurally at the single-cell level. Phylogenetic analysis demonstrates that the cocci cluster into an independent branch from other Alphaproteobacteria MTB, that is, within the Etaproteobacteria class in the Proteobacteria phylum. Statistical analysis reveals species-specific biomineralization of magnetosomal magnetite morphologies. This further confirms that magnetosome biomineralization is controlled strictly by the MTB cell and differs among species or strains. The post-mortem remains of MTB are often preserved as magnetofossils within sediments or sedimentary rocks, yet paleobiological and geological interpretation of their fossil record remains challenging. Our results indicate that magnetofossil morphology could be a promising proxy for retrieving paleobiological information about ancient MTB. 相似文献
313.
Tian-Yong Zhao David Martin Robert B. Meeley Bruce Downie 《Physiologia plantarum》2004,121(4):647-655
314.
315.
316.
QTL pyramiding for producing nutritious and safe rice grains 总被引:1,自引:0,他引:1
正Breeding of rice varieties that are enriched with essential micronutrients and simultaneously have reduced levels of toxic elements in grains is largely unexplored in rice breeding practice. In this issue of JIPB, Liu et al.(2020)developed two rice lines with a low level of cadmium and simultaneously high levels of zinc or selenium accumulation in the grains, thus providing elite genetic materials for breeding rice varieties that are important for addressing mineral malnutrition and ensuring food safety.m entary 相似文献
317.
Fei Wang Zhenjiang Yuan Zhiwei Zhao Caixia Li Xin Zhang Huafeng Liang Yawen Liu Qian Xu Hongtao Liu 《植物学报(英文版)》2020,62(2):247-255
Maize (Zea mays L.) is a monoecious grass plant in which mature male and female florets form the tassel and ear, respectively. Maize is often used as a model plant to study flower development. Several maize tassel seed mutants, such as the recessive mutants tasselseed1 (ts1) and tasselseed2 (ts2), exhibit a reversal in sex determination, which leads to the generation of seeds in tassels. The phenotype of the dominant mutant, Tasselseed5 (Ts5), is similar to that of ts2. Here, we positionally cloned the underlying gene of Ts5 and characterized its function. We show that the GRMZM2G177668 gene is overexpressed in Ts5. This gene encodes a cytochrome C oxidase, which catalyzes the transformation of jasmonoyl‐L‐isoleucine (JA‐Ile) to 12OH‐JA‐Ile during jasmonic acid catabolism. Consistent with this finding, no JA‐Ile peak was detected in Ts5 tassels during the sex determination period, unlike in the wild type. Transgenic maize plants overexpressing GRMZM2G177668 exhibited a tassel‐seed phenotype similar to that of Ts5. These results indicate that the JA‐Ile peak in tassels is critical for sex determination and that the Ts5 mutant phenotype results from the disruption of this peak in tassels during sex determination. 相似文献
318.
Qing‐Ping Zhao Jin‐Dong Zhu Nan‐Nan Li Xiao‐Nan Wang Xiang Zhao Xiao Zhang 《植物学报(英文版)》2020,62(5):614-630
Both phototropins(phot1 and phot2) and cryptochromes(cry1 and cry2) were proven as the Arabidopsis thaliana blue light receptors. Phototropins predominately function in photomovement, and cryptochromes play a role in photomorphogenesis. Although cryptochromes have been proposed to serve as positive modulators of phototropic responses, the underlying mechanism remains unknown. Here, we report that depleting sucrose from the medium or adding gibberellic acids(GAs) can partially restore the defects in phototropic curvature of the phot1 phot2 double mutants under high-intensity blue light; this restoration does not occur in phot1 phot2 cry1 cry2 quadruple mutants and nph3(nonphototropic hypocotyl 3) mutants which were impaired phototropic response in sucrose-containing medium. These results indicate that GAs and sucrose antagonistically regulate hypocotyl phototropism in a cryptochromes dependent manner, but it showed a crosstalk with phototropin signaling on NPH3.Furthermore, cryptochromes activation by blue light inhibit GAs synthesis, thus stabilizing DELLAs to block hypocotyl growth, which result in the higher GAs content in the shade side than the lit side of hypocotyl to support the asymmetric growth of hypocotyl. Through modulation of the abundance of DELLAs by sucrose depletion or added GAs, it revealed that cryptochromes have a function in mediating phototropic curvature. 相似文献
319.
320.
Natural variation in the promoter of OsHMA3 contributes to differential grain cadmium accumulation between Indica and Japonica rice 总被引:1,自引:0,他引:1
Chao‐Lei Liu Zhen‐Yu Gao Lian‐Guang Shang Chang‐Hong Yang Ban‐Pu Ruan Da‐Li Zeng Long‐Biao Guo Fang‐Jie Zhao Chao‐Feng Huang Qian Qian 《植物学报(英文版)》2020,62(3):314-329
Rice is a major source of cadmium(Cd) intake for Asian people. Indica rice usually accumulates more Cd in shoots and grains than Japonica rice. However, underlying genetic bases for differential Cd accumulation between Indica and Japonica rice are still unknown. In this study, we cloned a quantitative trait locus(QTL) grain Cd concentration on chromosome 7(GCC7) responsible for differential grain Cd accumulation between two rice varieties by performing QTL analysis and map-based cloning. We found that the two GCC7 alleles, GCC7~(PA64s) and GCC7~(93-11), had different promoter activity of OsHMA3,leading to different OsHMA3 expression and different shoot and grain Cd concentrations. By analyzing the distribution of different haplotypes of GCC7 among diverse rice accessions, we discovered that the high and low Cd accumulation alleles, namely GCC7~(93-11) and GCC7~(PA64s), were preferentially distributed in Indica and Japonica rice,respectively. We further showed that the GCC7~(PA64s)allele can be used to replace the GCC7~(93-11) allele in the super cultivar 93-11 to reduce grain Cd concentration without adverse effect on agronomic traits. Our results thus reveal that the QTL GCC7 with sequence variation in the OsHMA3 promoter is an important determinant controlling differential grain Cd accumulation between Indica and Japonica rice. 相似文献