Circular RNAs(circRNAs)form a class of endogenous single-stranded RNA transcripts that are widely expressed in eukaryotic cells.These RNAs mediate post-transcriptional control of gene expression and have multiple func...Circular RNAs(circRNAs)form a class of endogenous single-stranded RNA transcripts that are widely expressed in eukaryotic cells.These RNAs mediate post-transcriptional control of gene expression and have multiple functions in biological processes,such as transcriptional regulation and splicing.They serve predominantly as microRNA sponges,RNA-binding proteins,and templates for translation.More importantly,circRNAs are involved in cancer progression,and may serve as promising biomarkers for tumor diagnosis and therapy.Although traditional experimental methods are usually time-consuming and laborious,substantial progress has been made in exploring potential circRNA-disease associations by using computational models,summarized signaling pathway data,and other databases.Here,we review the biological characteristics and functions of circRNAs,including their roles in cancer.Specifically,we focus on the signaling pathways associated with carcinogenesis,and the status of circRNA-associated bioinformatics databases.Finally,we explore the potential roles of circRNAs as prognostic biomarkers in cancer.展开更多
Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rum...Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rumen-protected methionine and lysine(RML)in a low-protein(LP)diet on lipid metabolism,m^(6)A RNA methylation,and fatty acid(FA)profiles in the liver and muscle of lambs were investigated.Sixty-three male lambs were divided into three treatment groups,three pens per group and seven lambs per pen.The lambs were fed a 14.5%crude protein(CP)diet(adequate protein[NP]),12.5%CP diet(LP),and a LP diet plus RML(LP+RML)for 60 d.Results:The results showed that the addition of RML in a LP diet tended to lower the concentrations of plasma leptin(P=0.07),triglyceride(P=0.05),and non-esterified FA(P=0.08).Feeding a LP diet increased the enzyme activity or m RNA expression of lipogenic enzymes and decreased lipolytic enzymes compared with the NP diet.This effect was reversed by supplementation of RML with a LP diet.The inclusion of RML in a LP diet affected the polyunsaturated fatty acids(PUFA),n-3 PUFA,and n-6 PUFA in the liver but not in the muscle,which might be linked with altered expression of FA desaturase-1(FADS1)and acetyl-Co A carboxylase(ACC).A LP diet supplemented with RML increased(P<0.05)total m^(6)A levels in the liver and muscle and were accompanied by decreased expression of fat mass and obesity-associated protein(FTO)and alk B homologue 5(ALKBH5).The m RNA expressions of methyltransferase-like 3(METTL3)and methyltransferase-like 14(METTL14)in the LP+RML diet group were lower than those in the other two groups.Supplementation of RML with a LP diet affected only liver YTH domain family(YTHDF2)proteins(P<0.05)and muscle YTHDF3(P=0.09),which can be explained by limited m^(6)Abinding proteins that were mediated in m RNA fate.Conclusions:Our findings showed that the inclusion of RML in a LP diet could alter fat deposition through modulations of lipogenesis and lipolysis in the liver and muscle.These changes in fat metabolism may be associated with the modification of m^(6)A RNA methylation.展开更多
基金supported partly by the National Natural Science Foundation of China(Grant Nos.82172946,82173290,82273029,81871969,and 81772592)the Project of the Department of Education of Guangdong Province(Grant No.2021KTSCX102)+2 种基金the Natural Science Foundation of Guangdong Province(Grant No.2022A1515010706)the Shenzhen Basic Research Fund(Grant No.JCYJ20190808163801777)the SZU Top Ranking Project(Grant No.860-00000210)。
文摘Circular RNAs(circRNAs)form a class of endogenous single-stranded RNA transcripts that are widely expressed in eukaryotic cells.These RNAs mediate post-transcriptional control of gene expression and have multiple functions in biological processes,such as transcriptional regulation and splicing.They serve predominantly as microRNA sponges,RNA-binding proteins,and templates for translation.More importantly,circRNAs are involved in cancer progression,and may serve as promising biomarkers for tumor diagnosis and therapy.Although traditional experimental methods are usually time-consuming and laborious,substantial progress has been made in exploring potential circRNA-disease associations by using computational models,summarized signaling pathway data,and other databases.Here,we review the biological characteristics and functions of circRNAs,including their roles in cancer.Specifically,we focus on the signaling pathways associated with carcinogenesis,and the status of circRNA-associated bioinformatics databases.Finally,we explore the potential roles of circRNAs as prognostic biomarkers in cancer.
文摘为确定片烟在离散元仿真模拟中的合理模型参数取值,更好地计算出片烟在松散润叶设备中的复杂运动,基于离散元软件(Rocky DEM),创建了与以往球形黏结刚性颗粒模型不同的柔性片烟壳体模型,并分析了柔性片烟壳体模型形变特点。以物理和仿真试验的堆积角为对比对象,选取“Hysteretic Linear Spring”法向接触模型、“Linear Spring Coulomb Limit”切向接触模型以及“Constant Adhesive Force”黏附力模型,对仿真接触参数进行标定。再通过对片烟本征参数测定、查阅文献及Rocky DEM说明手册,分析得到了片烟的离散元参数取值范围,设计Plackett-Burman、最陡爬坡以及Box-Behnken试验,确定了影响柔性片烟堆积角的显著性参数以及堆积角的拟合方程。以堆积角物理试验35.83°为目标值,得到显著性参数的最优解:片烟与片烟间静摩擦系数为0.67,片烟与片烟间滑动摩擦系数为0.31,片烟与片烟黏间黏附力系数为0.2,其余非显著性参数取平均值。仿真试验与物理试验相对误差为0.78%,从而验证了模型的准确性与真实性,可为工业生产进一步计算柔性片烟在松散润叶装置内的运动提供理论依据。
基金funded by Chinese Academy of Sciences(Strategic Priority Research Program Grant NO.XDA26040304,XDA26050102)CAS Science and Technology Service Network Initiative(KFJ-STS-ZDTP-075)Innovation Province Project(2019RS3021)。
文摘Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rumen-protected methionine and lysine(RML)in a low-protein(LP)diet on lipid metabolism,m^(6)A RNA methylation,and fatty acid(FA)profiles in the liver and muscle of lambs were investigated.Sixty-three male lambs were divided into three treatment groups,three pens per group and seven lambs per pen.The lambs were fed a 14.5%crude protein(CP)diet(adequate protein[NP]),12.5%CP diet(LP),and a LP diet plus RML(LP+RML)for 60 d.Results:The results showed that the addition of RML in a LP diet tended to lower the concentrations of plasma leptin(P=0.07),triglyceride(P=0.05),and non-esterified FA(P=0.08).Feeding a LP diet increased the enzyme activity or m RNA expression of lipogenic enzymes and decreased lipolytic enzymes compared with the NP diet.This effect was reversed by supplementation of RML with a LP diet.The inclusion of RML in a LP diet affected the polyunsaturated fatty acids(PUFA),n-3 PUFA,and n-6 PUFA in the liver but not in the muscle,which might be linked with altered expression of FA desaturase-1(FADS1)and acetyl-Co A carboxylase(ACC).A LP diet supplemented with RML increased(P<0.05)total m^(6)A levels in the liver and muscle and were accompanied by decreased expression of fat mass and obesity-associated protein(FTO)and alk B homologue 5(ALKBH5).The m RNA expressions of methyltransferase-like 3(METTL3)and methyltransferase-like 14(METTL14)in the LP+RML diet group were lower than those in the other two groups.Supplementation of RML with a LP diet affected only liver YTH domain family(YTHDF2)proteins(P<0.05)and muscle YTHDF3(P=0.09),which can be explained by limited m^(6)Abinding proteins that were mediated in m RNA fate.Conclusions:Our findings showed that the inclusion of RML in a LP diet could alter fat deposition through modulations of lipogenesis and lipolysis in the liver and muscle.These changes in fat metabolism may be associated with the modification of m^(6)A RNA methylation.
