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SUMMARY: Cytochrome P450 proteins (CYPs) play critical roles in plant development and adaptation to fluctuating environments. Previous reports have shown that CYP86A proteins are involved in the biosynthesis of suberin and cutin in Arabidopsis. However, the functions of these proteins in rice remain obscure. In this study, a rice mutant with incomplete male sterility was identified. Cytological analyses revealed that this mutant was defective in anther development. Cloning of the mutant gene indicated that the responsible mutation was on OsCYP86A9. OsMYB80 is a core transcription factor in the regulation of rice anther development. The expression of OsCYP86A9 was abolished in the anther of osmyb80 mutant. In vivo and in vitro experiments showed that OsMYB80 binds to the MYB‐binding motifs in OsCYP86A9 promoter region and regulates its expression. Furthermore, the oscyp86a9 mutant exhibited an impaired suberin deposition in the root, and was more susceptible to drought stress. Interestingly, genetic and biochemical analyses revealed that OsCYP86A9 expression was regulated in the root by certain MYB transcription factors other than OsMYB80. Moreover, mutations in the MYB genes that regulate OsCYP86A9 expression in the root did not impair the male fertility of the plant. Taken together, these findings revealed the critical roles of OsCYP86A9 in plant development and proposed that OsCYP86A9 functions in anther development and root suberin formation via two distinct tissue‐specific regulatory pathways. Significance Statement: The cytochrome P450 subfamily CYP86A is very important for plant development. However, their functions remain obscure in rice. Here, we reported that OsCYP86A9, a member of CYP86A subfamily, is critical for the development of anther and root suberin, and these functions are determined by two distinct tissue‐specific regulatory pathways. [ABSTRACT FROM AUTHOR]

Obesity is caused by an imbalance between energy intake and energy expenditure. This study aimed to determine the effects and mechanisms of 2′,4′‐dihydroxy‐6′‐methoxy‐3′,5′‐dimethylchalcone (DMC) on exercise tolerance in high‐fat diet (HFD)‐fed mice. Male C57BL/6J mice were randomly divided into two categories (7 groups [n = 8]): sedentary (control [CON], HFD, 200 mg/kg DMC, and 500 mg/kg DMC) and swimming (HFD, 200 mg/kg DMC, and 500 mg/kg DMC). Except the CON group, all other groups were fed HFD with or without DMC intervention for 33 days. The swimming groups were subjected to exhaustive swimming (three sessions/week). Changes in swimming time, glucolipid metabolism, body composition, biochemical indicators, histopathology, inflammation, metabolic mediators, and protein expression were assessed. DMC combined with regular exercise improved endurance performance, body composition, glucose and insulin tolerance, lipid profile, and the inflammatory state in a dose‐dependent manner. Further, DMC alone or combined with exercise could restore normal tissue morphology, reduce fatigue‐associated markers, and boost whole‐body metabolism and the protein expression of phospho‐AMP‐activated protein kinase alpha/total‐AMP‐activated protein kinase alpha (AMPK), sirtuin‐1 (SIRT1), peroxisome‐proliferator‐activated receptor gamma coactivator 1alpha (PGC‐1α), and peroxisome proliferator‐activated receptor alpha in the muscle and adipose tissues of HFD‐fed mice. DMC exhibits antifatigue effects by regulating glucolipid catabolism, inflammation, and energy homeostasis. Furthermore, DMC exerts a synergistic exercise‐related metabolic effect via the AMPK‐SIRT1‐PGC‐1α signaling pathway, suggesting that DMC is a potential natural sports supplement with mimicked or augmented exercise effects for obesity prevention. [ABSTRACT FROM AUTHOR]

SUMMARY: Cold stress is a major factor limiting the production and geographical distribution of rice (Oryza sativa) varieties. However, the molecular mechanisms underlying cold tolerance remain to be elucidated. Here, we report that ornithine δ‐aminotransferase (OsOAT) contributes to cold tolerance during the vegetative and reproductive development of rice. osoat mutant was identified as a temperature‐sensitive male sterile mutant with deformed floral organs and seedlings sensitive to cold stress. Comparative transcriptome analysis showed that OsOAT mutation and cold treatment of the wild‐type plant led to similar changes in the global gene expression profiles in anthers. OsOAT genes in indica rice Huanghuazhan (HHZ) and japonica rice Wuyungeng (WYG) are different in gene structure and response to cold. OsOAT is cold‐inducible in WYG but cold‐irresponsive in HHZ. Further studies showed that indica varieties carry both WYG‐type and HHZ‐type OsOAT, whereas japonica varieties mostly carry WYG‐type OsOAT. Cultivars carrying HHZ‐type OsOAT are mainly distributed in low‐latitude regions, whereas varieties carrying WYG‐type OsOAT are distributed in both low‐ and high‐latitude regions. Moreover, indica varieties carrying WYG‐type OsOAT generally have higher seed‐setting rates than those carrying HHZ‐type OsOAT under cold stress at reproductive stage, highlighting the favorable selection for WYG‐type OsOAT during domestication and breeding to cope with low temperatures. Significance Statement: The identification of genes important for cold tolerance can promote the molecular breeding of cold‐tolerant rice varieties. This study discovered two major natural alleles of OsOAT that conferred different levels of cold tolerance, thereby providing a good candidate gene for breeding of rice plants with enhanced cold tolerance. [ABSTRACT FROM AUTHOR]

Pollen exine contains complex biopolymers of aliphatic lipids and phenolics. Abnormal development of pollen exine often leads to plant sterility. Molecular mechanisms regulating exine formation have been studied extensively but remain ambiguous. Here we report the analyses of three GDSL esterase/lipase protein genes, OsGELP34, OsGELP110, and OsGELP115, for rice exine formation. OsGELP34 was identified by cloning of a male sterile mutant gene. OsGELP34 encodes an endoplasmic reticulum protein and was mainly expressed in anthers during pollen exine formation. osgelp34 mutant displayed abnormal exine and altered expression of a number of key genes required for pollen development. OsGELP110 was previously identified as a gene differentially expressed in meiotic anthers. OsGELP110 was most homologous to OsGELP115, and the two genes showed similar gene expression patterns. Both OsGELP110 and OsGELP115 proteins were localized in peroxisomes. Individual knockout of OsGELP110 and OsGELP115 did not affect the plant fertility, but double knockout of both genes altered the exine structure and rendered the plant male sterile. OsGELP34 is distant from OsGELP110 and OsGELP115 in sequence, and osgelp34 and osgelp110/osgelp115 mutants were different in anther morphology despite both were male sterile. These results suggested that OsGELP34 and OsGELP110/OsGELP115 catalyze different compounds for pollen exine development. [ABSTRACT FROM AUTHOR]

Pollen grains are covered by exine that protects the pollen from stress and facilitates pollination. Here we isolated a male sterile mutant s13283 in rice exhibiting aborted pollen with abnormal exine and defective aperture. The mutant gene encodes a novel plasma membrane‐localized legume‐lectin receptor kinase that we named OsLecRK‐S.7. OsLecRK‐S.7 was expressed at different levels in all tested tissues and throughout anther development. In vitro kinase assay showed OsLecRK‐S.7 capable of autophosporylation. Mutation in s13283 (E560K) and mutation of the conserved ATP binding site (K418E) both knocked out the kinase activity. Mass spectrometry showed Thr376, Ser378, Thr386, Thr403, and Thr657 to be the autophosphorylation sites. Mutation of individual autophosphorylation site affected the in vitro kinase activity to different degrees, but did not abolish the gene function in fertility complementation. oslecrk‐s.7 mutant plant overexpressing OsLecRK‐S.7 recovered male fertility but showed severe growth retardation with reduced number of tillers, and these phenotypes were abolished by E560K or K418E mutation. The results indicated that OsLecRK‐S.7 was a key regulator of pollen development. [ABSTRACT FROM AUTHOR]

The initial alignment is vital to the inertial navigation system of a cruise vehicle. The existing initial fine alignment methods in the erection process are mostly dependent on other equipment to provide measurements, which increase the complexity and cost of the system and may cause some measurement error and noise. To solve this problem, an initial fine alignment method based on self‐contained measurement is proposed and executed during the erection process with a static base. The self‐contained measurement is obtained through the modelling of a multi‐level dynamic lever arm. Using the self‐contained measurement, the fine alignment model is derived and the precision of initial fine alignment can be improved. Finally, experiments were carried out and verified the validity of the proposed method. [ABSTRACT FROM AUTHOR]