A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the f...A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the ferrimagnetic matrix.Additionally,the exchange bias effect is gradually pronounced with the positive increase in the cooling field,known as the conventional exchange bias effect.However,as the cooling field gradually decreases and transits from positive to negative,the exchange bias effect can robustly remain positive in the low-negative-field region until the cooling field increases to be sufficiently large in the negative direction.展开更多
Acute mitochondrial damage and the energy crisis following axonal injury highlight mitochondrial transport as an important target for axonal regeneration.Syntaphilin(Snph),known for its potent mitochondrial anchoring ...Acute mitochondrial damage and the energy crisis following axonal injury highlight mitochondrial transport as an important target for axonal regeneration.Syntaphilin(Snph),known for its potent mitochondrial anchoring action,has emerged as a significant inhibitor of both mitochondrial transport and axonal regeneration.Therefore,investigating the molecular mechanisms that influence the expression levels of the snph gene can provide a viable strategy to regulate mitochondrial trafficking and enhance axonal regeneration.Here,we reveal the inhibitory effect of microRNA-146b(miR-146b)on the expression of the homologous zebrafish gene syntaphilin b(snphb).Through CRISPR/Cas9 and single-cell electroporation,we elucidated the positive regulatory effect of the miR-146b-snphb axis on Mauthner cell(M-cell)axon regeneration at the global and single-cell levels.Through escape response tests,we show that miR-146b-snphb signaling positively regulates functional recovery after M-cell axon injury.In addition,continuous dynamic imaging in vivo showed that reprogramming miR-146b significantly promotes axonal mitochondrial trafficking in the pre-injury and early stages of regeneration.Our study reveals an intrinsic axonal regeneration regulatory axis that promotes axonal regeneration by reprogramming mitochondrial transport and anchoring.This regulation involves noncoding RNA,and mitochondria-associated genes may provide a potential opportunity for the repair of central nervous system injury.展开更多
Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality ...Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia.However,it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate.Here,to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species,we assessed the genetic variability and demographic history of T.heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I(COI)sequences.We observed high haplotype diversity(Hd),with an average of 0.926,but relatively low nucleotide diversity(π),with a mean of 0.032 across all samples.A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals.The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067,with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation.Significant genetic structures were revealed among the studied locations;specifically,the eight locations could be treated as six genetically different populations based on pairwiseΦST results(0.026–0.951,P<0.01).A significant pattern of isolation-by-distance was detected between the genetic and geographic distances(r=0.873,P=0.001).Three geographic lineages were defined based on phylogenetic tree and network analyses of COI haplotypes.AMOVA results indicated that genetic variations mainly occurred among the three lineages(89.96%).Tests of neutrality and mismatch distribution suggested that T.heterochaetus underwent recent population expansion.These results provide the first report on the genetic status of T.heterochaetus and will be valuable for the management of genetic resources and better understanding of the ecology and evolution in this species.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.11474111 and 11604281)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20220618)the Hundreds of Talents program of Sun Yat-sen University(No.210192)
文摘A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the ferrimagnetic matrix.Additionally,the exchange bias effect is gradually pronounced with the positive increase in the cooling field,known as the conventional exchange bias effect.However,as the cooling field gradually decreases and transits from positive to negative,the exchange bias effect can robustly remain positive in the low-negative-field region until the cooling field increases to be sufficiently large in the negative direction.
基金supported by the core facility Center for Life Sciences,University of Science and Technology of China,Research Funds of the Center for Advanced Interdisciplinary Science and Biomedicine of IHM(QYZD20220002)the National Natural Science Foundation of China(82071357)the Ministry of Science and Technology of China(2019YFA0405600).
文摘Acute mitochondrial damage and the energy crisis following axonal injury highlight mitochondrial transport as an important target for axonal regeneration.Syntaphilin(Snph),known for its potent mitochondrial anchoring action,has emerged as a significant inhibitor of both mitochondrial transport and axonal regeneration.Therefore,investigating the molecular mechanisms that influence the expression levels of the snph gene can provide a viable strategy to regulate mitochondrial trafficking and enhance axonal regeneration.Here,we reveal the inhibitory effect of microRNA-146b(miR-146b)on the expression of the homologous zebrafish gene syntaphilin b(snphb).Through CRISPR/Cas9 and single-cell electroporation,we elucidated the positive regulatory effect of the miR-146b-snphb axis on Mauthner cell(M-cell)axon regeneration at the global and single-cell levels.Through escape response tests,we show that miR-146b-snphb signaling positively regulates functional recovery after M-cell axon injury.In addition,continuous dynamic imaging in vivo showed that reprogramming miR-146b significantly promotes axonal mitochondrial trafficking in the pre-injury and early stages of regeneration.Our study reveals an intrinsic axonal regeneration regulatory axis that promotes axonal regeneration by reprogramming mitochondrial transport and anchoring.This regulation involves noncoding RNA,and mitochondria-associated genes may provide a potential opportunity for the repair of central nervous system injury.
基金supported by the IndustryAcademic Research Cooperation Program of Academician Workstation of Guangdong Province(2013B090400017)Natural Science Foundation of Guangdong Province(2016A030307036)Yangfan Innovative&Entrepreneurial Research Team Project for Guangdong Province(201312H10)
文摘Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia.However,it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate.Here,to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species,we assessed the genetic variability and demographic history of T.heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I(COI)sequences.We observed high haplotype diversity(Hd),with an average of 0.926,but relatively low nucleotide diversity(π),with a mean of 0.032 across all samples.A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals.The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067,with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation.Significant genetic structures were revealed among the studied locations;specifically,the eight locations could be treated as six genetically different populations based on pairwiseΦST results(0.026–0.951,P<0.01).A significant pattern of isolation-by-distance was detected between the genetic and geographic distances(r=0.873,P=0.001).Three geographic lineages were defined based on phylogenetic tree and network analyses of COI haplotypes.AMOVA results indicated that genetic variations mainly occurred among the three lineages(89.96%).Tests of neutrality and mismatch distribution suggested that T.heterochaetus underwent recent population expansion.These results provide the first report on the genetic status of T.heterochaetus and will be valuable for the management of genetic resources and better understanding of the ecology and evolution in this species.
