By critical point theory, a new approach is provided to study the existence and multiplicity results of periodic and subharmonic solutions for difference equations. For secord-order difference equations $$\Delta ^2 x_...By critical point theory, a new approach is provided to study the existence and multiplicity results of periodic and subharmonic solutions for difference equations. For secord-order difference equations $$\Delta ^2 x_{n - 1} + f(n, x_n ) = 0,$$ some new results are obtained for the above problems when f(t, z) has superlinear growth at zero and at infinity in z.展开更多
tRNA-derived small RNAs(tsRNAs),including tRNA-derived fragments(tRFs)and tRNA halves(tiRNAs),are small regulatory RNAs processed from mature tRNAs or precursor tRNAs.tRFs and tiRNAs play biological roles through a va...tRNA-derived small RNAs(tsRNAs),including tRNA-derived fragments(tRFs)and tRNA halves(tiRNAs),are small regulatory RNAs processed from mature tRNAs or precursor tRNAs.tRFs and tiRNAs play biological roles through a variety of mechanisms by interacting with proteins or mRNA,inhibiting translation,and regulating gene expression,the cell cycle,and chromatin and epigenetic modifications.The establishment and application of research technologies are important in understanding the biological roles of tRFs and tiRNAs.To study the molecular mechanisms of tRFs and tiRNAs,researchers have used a variety of bioinformatics and molecular biology methods,such as microarray analysis,real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR);Northern blotting;RNA sequencing(RNA-seq);cross-linking,ligation and sequencing of hybrids(CLASH);and photoactivatable-ribonucleoside-enhanced cross-linking and immunoprecipitation(PAR-CLIP).This paper summarizes the classification,action mechanisms,and roles of tRFs and tiRNAs in human diseases and the related signal transduction pathways,targeted therapies,databases,and research methods associated with them.展开更多
Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regi...Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regions.Here,we report a highly continuous and completely gap-free reference genome of Actinidia chinensis cv.‘Hongyang’,named Hongyang v4.0,which is the first to achieve two de novo haploid-resolved haplotypes,HY4P and HY4A.HY4P and HY4A have a total length of 606.1 and 599.6 Mb,respectively,with almost the entire telomeres and centromeres assembled in each haplotype.In comparison with Hongyang v3.0,the integrity and contiguity of Hongyang v4.0 is markedly improved by filling all unclosed gaps and correcting some misoriented regions,resulting in∼38.6–39.5 Mb extra sequences,which might affect 4263 and 4244 protein-coding genes in HY4P and HY4A,respectively.Furthermore,our gap-free genome assembly provides the first clue for inspecting the structure and function of centromeres.Globally,centromeric regions are characterized by higher-order repeats that mainly consist of a 153-bp conserved centromere-specific monomer(Ach-CEN153)with different copy numbers among chromosomes.Functional enrichment analysis of the genes located within centromeric regions demonstrates that chromosome centromeres may not only play physical roles for linking a pair of sister chromatids,but also have genetic features for participation in the regulation of cell division.The availability of the telomere-to-telomere and gap-free Hongyang v4.0 reference genome lays a solid foundation not only for illustrating genome structure and functional genomics studies but also for facilitating kiwifruit breeding and improvement.展开更多
基金This work was supported by the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institutions of MOE of Chinaby the Trans-Century Training Programme Foundation for the Talents of the State Education Commissionby the National Natural Science Foundation of China(Grant No.19831030).
文摘By critical point theory, a new approach is provided to study the existence and multiplicity results of periodic and subharmonic solutions for difference equations. For secord-order difference equations $$\Delta ^2 x_{n - 1} + f(n, x_n ) = 0,$$ some new results are obtained for the above problems when f(t, z) has superlinear growth at zero and at infinity in z.
基金supported by grants from the National Natural Science Foundation of China(no.81974316)the Scientific Innovation Team Project of Ningbo(no.2017C110019)+1 种基金Zhejiang Key Laboratory of Pathophysiology(no.202001)the K.C.Wong Magna Fund in Ningbo University.
文摘tRNA-derived small RNAs(tsRNAs),including tRNA-derived fragments(tRFs)and tRNA halves(tiRNAs),are small regulatory RNAs processed from mature tRNAs or precursor tRNAs.tRFs and tiRNAs play biological roles through a variety of mechanisms by interacting with proteins or mRNA,inhibiting translation,and regulating gene expression,the cell cycle,and chromatin and epigenetic modifications.The establishment and application of research technologies are important in understanding the biological roles of tRFs and tiRNAs.To study the molecular mechanisms of tRFs and tiRNAs,researchers have used a variety of bioinformatics and molecular biology methods,such as microarray analysis,real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR);Northern blotting;RNA sequencing(RNA-seq);cross-linking,ligation and sequencing of hybrids(CLASH);and photoactivatable-ribonucleoside-enhanced cross-linking and immunoprecipitation(PAR-CLIP).This paper summarizes the classification,action mechanisms,and roles of tRFs and tiRNAs in human diseases and the related signal transduction pathways,targeted therapies,databases,and research methods associated with them.
基金supported by funds from the National Natural Science Foundation of China(31972474,90717110)Hubei Natural Science Fund for Distinguished Young Scholars(2020CFA062).
文摘Kiwifruit is an economically and nutritionally important fruit crop with extremely high contents of vitamin C.However,the previously released versions of kiwifruit genomes all have a mass of unanchored or missing regions.Here,we report a highly continuous and completely gap-free reference genome of Actinidia chinensis cv.‘Hongyang’,named Hongyang v4.0,which is the first to achieve two de novo haploid-resolved haplotypes,HY4P and HY4A.HY4P and HY4A have a total length of 606.1 and 599.6 Mb,respectively,with almost the entire telomeres and centromeres assembled in each haplotype.In comparison with Hongyang v3.0,the integrity and contiguity of Hongyang v4.0 is markedly improved by filling all unclosed gaps and correcting some misoriented regions,resulting in∼38.6–39.5 Mb extra sequences,which might affect 4263 and 4244 protein-coding genes in HY4P and HY4A,respectively.Furthermore,our gap-free genome assembly provides the first clue for inspecting the structure and function of centromeres.Globally,centromeric regions are characterized by higher-order repeats that mainly consist of a 153-bp conserved centromere-specific monomer(Ach-CEN153)with different copy numbers among chromosomes.Functional enrichment analysis of the genes located within centromeric regions demonstrates that chromosome centromeres may not only play physical roles for linking a pair of sister chromatids,but also have genetic features for participation in the regulation of cell division.The availability of the telomere-to-telomere and gap-free Hongyang v4.0 reference genome lays a solid foundation not only for illustrating genome structure and functional genomics studies but also for facilitating kiwifruit breeding and improvement.
