Animals interact with their environments all the time,and must react to all kinds of factors present in the environments.Environmental RNA interference refers to the phenomenon that exogenous RNA molecules can enter c...Animals interact with their environments all the time,and must react to all kinds of factors present in the environments.Environmental RNA interference refers to the phenomenon that exogenous RNA molecules can enter cells of certain animal species and interfere with gene expression of these animals.These exogenous RNAs may be molecules in animal food,or may be present in the living environment from other sources.Molecular pathways for the cell entry of environmental RNAs and further for their functionality in gene interference have started to be revealed in the animal model Caenorhabditis elegans.Here we highlight some known examples of environmental RNA interference(RNAi)in animals and introduce the molecular mechanisms underneath.展开更多
α-latrotoxin (α-LTX), a neurotoxin from black-widow spider, causes vesicles release in pre- synapse of nerve terminal after binding to specific membrane receptors. α-LTXN4C is an effective tool binding to calcium i...α-latrotoxin (α-LTX), a neurotoxin from black-widow spider, causes vesicles release in pre- synapse of nerve terminal after binding to specific membrane receptors. α-LTXN4C is an effective tool binding to calcium independent receptor for latrotoxin (CIRL), which is used to elucidate the mechanism of receptor-mediated signal pathway. In our study on the pancreatic β cells, we found that α-LTX inserts into the plasma membrane and forms stable non-selective cation channels. The influx of ex- tracellular Ca2+ through the channels causes massive Ca2+-dependent exocytosis of insulin-containing vesicles, whereas, α-LTXN4C, binding with its receptor CIRL in extracellular divalent cation-dependent way, increases [Ca2+]i by mobilization of the intracellular calcium stores.展开更多
The molecular mechanisms by which dense core vesicles(DCVs) translocate,tether,dock and prime are poorly understood.In this study,Caenorhabditis elegans was used as a model organism to study the function of Rab protei...The molecular mechanisms by which dense core vesicles(DCVs) translocate,tether,dock and prime are poorly understood.In this study,Caenorhabditis elegans was used as a model organism to study the function of Rab proteins and their effectors in DCV exocytosis.RAB-27/AEX-6,but not RAB-3,was found to be required for peptide release from neurons.By analyzing the movement of DCVs approaching the plasma membrane using total internal reflection fluorescence microscopy,we demonstrated that RAB-27/AEX-6 is involved in the tethering of DCVs and that its effector rabphilin/RBF-1 is required for the initial tethering and subsequent stabilization by docking.展开更多
In this paper,we present an overview of the mechanical design and control of biomimetic robotic fishes with high maneuverability.The robotic fishes modelled after Esoxlucius adopt multilink propulsive mechanism for a ...In this paper,we present an overview of the mechanical design and control of biomimetic robotic fishes with high maneuverability.The robotic fishes modelled after Esoxlucius adopt multilink propulsive mechanism for a high turning rate and a small turning radius.According to different tasks,these robotic fishes are designed with decorated pectoral fins for a two-dimensional horizon plane,or controllable pectoral fins with multiple degrees of freedom for a three-dimensional space.Through observing and analyzing the fast-starts of real fish,we separately develop a dynamic trajectory tracking strategy based C-start control method and an L-shaped sliding method based S-start control method.Finally,a four-link robotic fish is able to execute C-start flexibly with a turning angle of up to 213°,a top turning rate of approximately670°/s,and an upper limit of turning precision of less than 10°and an S-start with a peak turning rate up to318.08±9.20°/s.The experimental results verify the feasibility of our high-maneuverability-oriented mechatronic design and control methods.展开更多
基金supported by the National Basic Research Program of China(2011CBA01103)National Natural Science Foundation of China(81171074,91232702,and 31071132)the Knowledge Innovation Project of CAS(1731112304041)to G.Shan
文摘Animals interact with their environments all the time,and must react to all kinds of factors present in the environments.Environmental RNA interference refers to the phenomenon that exogenous RNA molecules can enter cells of certain animal species and interfere with gene expression of these animals.These exogenous RNAs may be molecules in animal food,or may be present in the living environment from other sources.Molecular pathways for the cell entry of environmental RNAs and further for their functionality in gene interference have started to be revealed in the animal model Caenorhabditis elegans.Here we highlight some known examples of environmental RNA interference(RNAi)in animals and introduce the molecular mechanisms underneath.
基金We thank Prof.Yuri Ushkaryov for supplying α-LTXN4C.This work was supported by the National Natural Science Foundation of China(Grant Nos.30270363&30130230)the National Basic Research Program of China(Grant Nos.G1999054000&2004CB720000).
文摘α-latrotoxin (α-LTX), a neurotoxin from black-widow spider, causes vesicles release in pre- synapse of nerve terminal after binding to specific membrane receptors. α-LTXN4C is an effective tool binding to calcium independent receptor for latrotoxin (CIRL), which is used to elucidate the mechanism of receptor-mediated signal pathway. In our study on the pancreatic β cells, we found that α-LTX inserts into the plasma membrane and forms stable non-selective cation channels. The influx of ex- tracellular Ca2+ through the channels causes massive Ca2+-dependent exocytosis of insulin-containing vesicles, whereas, α-LTXN4C, binding with its receptor CIRL in extracellular divalent cation-dependent way, increases [Ca2+]i by mobilization of the intracellular calcium stores.
基金supported by the National Basic Research Program of China(Grant No. 2010CB833701)the National Natural Science Foundation of China(Grant Nos. 30870564 and 90913022)the CAS Project(Grant No.KSCX2-SW-224)
文摘The molecular mechanisms by which dense core vesicles(DCVs) translocate,tether,dock and prime are poorly understood.In this study,Caenorhabditis elegans was used as a model organism to study the function of Rab proteins and their effectors in DCV exocytosis.RAB-27/AEX-6,but not RAB-3,was found to be required for peptide release from neurons.By analyzing the movement of DCVs approaching the plasma membrane using total internal reflection fluorescence microscopy,we demonstrated that RAB-27/AEX-6 is involved in the tethering of DCVs and that its effector rabphilin/RBF-1 is required for the initial tethering and subsequent stabilization by docking.
基金supported by the National Natural Science Foundation of China(Grant Nos.61375102, 61333016 and 61421004)
文摘In this paper,we present an overview of the mechanical design and control of biomimetic robotic fishes with high maneuverability.The robotic fishes modelled after Esoxlucius adopt multilink propulsive mechanism for a high turning rate and a small turning radius.According to different tasks,these robotic fishes are designed with decorated pectoral fins for a two-dimensional horizon plane,or controllable pectoral fins with multiple degrees of freedom for a three-dimensional space.Through observing and analyzing the fast-starts of real fish,we separately develop a dynamic trajectory tracking strategy based C-start control method and an L-shaped sliding method based S-start control method.Finally,a four-link robotic fish is able to execute C-start flexibly with a turning angle of up to 213°,a top turning rate of approximately670°/s,and an upper limit of turning precision of less than 10°and an S-start with a peak turning rate up to318.08±9.20°/s.The experimental results verify the feasibility of our high-maneuverability-oriented mechatronic design and control methods.
