The intracellular signaling pathways through ADP-ribosylation factors (Arfs) of the small GTPase family control cell morphological changes by regulating membrane components and/or cytoskeletal protein dynamics. We pre...The intracellular signaling pathways through ADP-ribosylation factors (Arfs) of the small GTPase family control cell morphological changes by regulating membrane components and/or cytoskeletal protein dynamics. We previously reported that cytohesin-2 (CYTH2), an Arf-guanine-nucleotide exchange factor (GEF), binds to the cytoskeletal scaffold protein paxillin through C-terminal region of CYTH2 and promotes the migration of mouse 3T3-L1 fibroblasts. In mammals, CYTH family GEFs are composed of four subfamilies. Among them, CYTH2 and CYTH3 are widely expressed in tissues and it remains to be clarified to determine whether they have specific biochemical and cellular functions or are redundant. Here, we show that the C-terminal short polybasic region of CYTH2 is necessary and sufficient for binding to paxillin to mediate cell migration. Although 3T3-L1 cells primarily express CYTH2 and CYTH3 of four CYTH family members, neither knockdown of CYTH3 by the specific siRNA nor expression of its C-terminal region inhibits migration. Importantly, replacing the C-terminal region of CYTH3 with that of CYTH2 adds the ability of paxillinbinding and mediating migration to CYTH3. Conversely, replacing the C- terminal region of CYTH2 with that of CYTH3 leads to loss of these abilities of CYTH2. These results reveal that paxillin is a unique binding partner with CYTH2 in migrating cells, presenting the first CYTH family GEF’s region that is involved in the selectivity of the binding protein.展开更多
By introducing oxalic acid,succinic acid,and tartaric acid into the synthesis process of Mo-V-O composite metal oxides,the structure directing effect of polybasic organic acids on the crystal structure of Mo-V-O compo...By introducing oxalic acid,succinic acid,and tartaric acid into the synthesis process of Mo-V-O composite metal oxides,the structure directing effect of polybasic organic acids on the crystal structure of Mo-V-O compositee metal oxide was studied.Moreover,the prepared Mo-V-O samples with different crystal phase compositions were used to the conversion of glycerol,and the effect of crystal phase structure on its catalytic performance was investigated.Results show that the crystal phase structure of Mo-V-O can be regulated by changing the type and additive amount of polybasic organic acids.The crystal phase of Mo-V-O changed from MoV_(2)O_(8)to Mo_(0.97)V_(0.95)O_(5)with the increase of succinic acid and tartaric acid.The change in the Mo-V-O crystal phase is related to the amount of organic acid and the carbon chain length.When the crystal phase is MoV_(2)O_(8),the selectivity of acrolein and acetone is 25.7%and 16.2%.According to the XPS results,Mo^(6+)in MoV_(2)O_(8)promoted the formation of acrolein,while Mo^(5+)in Mo0.97V0.95O5 promoted the formation of acetone.So when the crystal phase is Mo0.97V0.95O5,the selectivity of acrolein and acetone is 11.9%and 24.6%.Therefore,the results of catalyzing glycerol can be controlled by selecting different crystal phases.展开更多
When the conventional sandstone acidizing technologies are adopted,many slugs are needed in the injection of prepad fluid,treatment fluid and postpad fluid,and consequently the production and operation suffers inconve...When the conventional sandstone acidizing technologies are adopted,many slugs are needed in the injection of prepad fluid,treatment fluid and postpad fluid,and consequently the production and operation suffers inconveniences and difficulties.In view of this,a kind of HA integrated acid system which is mainly composed of organic polybasic acids(HA)+HCl+HF and an efficient organic solvent was developed in this paper based on the idea of integrated acid replacing"multiple steps"and high efficiency and intensification.Via this HA integrated acid system,the complicated blockage in sandstone reservoirs can be removed effectively.Then,experiments were carried out on this system to evaluate its performance in terms of its retardance,organic blockage dissolution,chelating and precipitation inhibition.It is indicated that this new system can not only realize the acidizing of conventional integrated acid,but also present a good retarding performance by controlling Ht multi-stage ionization step by step and by forming silica acid-aluminum phosphonate film on the surface of clay minerals;that via this new HA integrated acid system,the organic blockage can be removed efficiently;and that it is wider in pH solution range than conventional APCs(aminopolycarboxyliates)chelants,stronger in chelating capacity of Ca^(2+),Mg^(2+)and Fe^(3+)than conventional chelants(e.g.EDTA,NTA and DTPA),and better in precipitation inhibition on metal fluoride,fluosilicic acid alkali metal,fluoaluminic acid alkali metal and hydroxide than multihydrogen acid,fluoboric acid and mud acid systems.These research results provide a technical support for the plugging removal in hightemperature deep oil and gas reservoirs.展开更多
文摘The intracellular signaling pathways through ADP-ribosylation factors (Arfs) of the small GTPase family control cell morphological changes by regulating membrane components and/or cytoskeletal protein dynamics. We previously reported that cytohesin-2 (CYTH2), an Arf-guanine-nucleotide exchange factor (GEF), binds to the cytoskeletal scaffold protein paxillin through C-terminal region of CYTH2 and promotes the migration of mouse 3T3-L1 fibroblasts. In mammals, CYTH family GEFs are composed of four subfamilies. Among them, CYTH2 and CYTH3 are widely expressed in tissues and it remains to be clarified to determine whether they have specific biochemical and cellular functions or are redundant. Here, we show that the C-terminal short polybasic region of CYTH2 is necessary and sufficient for binding to paxillin to mediate cell migration. Although 3T3-L1 cells primarily express CYTH2 and CYTH3 of four CYTH family members, neither knockdown of CYTH3 by the specific siRNA nor expression of its C-terminal region inhibits migration. Importantly, replacing the C-terminal region of CYTH3 with that of CYTH2 adds the ability of paxillinbinding and mediating migration to CYTH3. Conversely, replacing the C- terminal region of CYTH2 with that of CYTH3 leads to loss of these abilities of CYTH2. These results reveal that paxillin is a unique binding partner with CYTH2 in migrating cells, presenting the first CYTH family GEF’s region that is involved in the selectivity of the binding protein.
基金Support Program,China(No.RC210184)Basic Research Projects of Liaoning Provincial Department of Education,China(No.JYTMS20231497)+1 种基金LiaoNing Revitalization Talents Program(No.XLYC2002001)Applied Basic Research Programs of Liaoning Province(No.2023JH2/101300243).
文摘By introducing oxalic acid,succinic acid,and tartaric acid into the synthesis process of Mo-V-O composite metal oxides,the structure directing effect of polybasic organic acids on the crystal structure of Mo-V-O compositee metal oxide was studied.Moreover,the prepared Mo-V-O samples with different crystal phase compositions were used to the conversion of glycerol,and the effect of crystal phase structure on its catalytic performance was investigated.Results show that the crystal phase structure of Mo-V-O can be regulated by changing the type and additive amount of polybasic organic acids.The crystal phase of Mo-V-O changed from MoV_(2)O_(8)to Mo_(0.97)V_(0.95)O_(5)with the increase of succinic acid and tartaric acid.The change in the Mo-V-O crystal phase is related to the amount of organic acid and the carbon chain length.When the crystal phase is MoV_(2)O_(8),the selectivity of acrolein and acetone is 25.7%and 16.2%.According to the XPS results,Mo^(6+)in MoV_(2)O_(8)promoted the formation of acrolein,while Mo^(5+)in Mo0.97V0.95O5 promoted the formation of acetone.So when the crystal phase is Mo0.97V0.95O5,the selectivity of acrolein and acetone is 11.9%and 24.6%.Therefore,the results of catalyzing glycerol can be controlled by selecting different crystal phases.
基金Project supported by National Science and Technology Major Project“Development of Large Oil and Gas Fields and Coalbed Methane”(No.2016ZX05058-003).
文摘When the conventional sandstone acidizing technologies are adopted,many slugs are needed in the injection of prepad fluid,treatment fluid and postpad fluid,and consequently the production and operation suffers inconveniences and difficulties.In view of this,a kind of HA integrated acid system which is mainly composed of organic polybasic acids(HA)+HCl+HF and an efficient organic solvent was developed in this paper based on the idea of integrated acid replacing"multiple steps"and high efficiency and intensification.Via this HA integrated acid system,the complicated blockage in sandstone reservoirs can be removed effectively.Then,experiments were carried out on this system to evaluate its performance in terms of its retardance,organic blockage dissolution,chelating and precipitation inhibition.It is indicated that this new system can not only realize the acidizing of conventional integrated acid,but also present a good retarding performance by controlling Ht multi-stage ionization step by step and by forming silica acid-aluminum phosphonate film on the surface of clay minerals;that via this new HA integrated acid system,the organic blockage can be removed efficiently;and that it is wider in pH solution range than conventional APCs(aminopolycarboxyliates)chelants,stronger in chelating capacity of Ca^(2+),Mg^(2+)and Fe^(3+)than conventional chelants(e.g.EDTA,NTA and DTPA),and better in precipitation inhibition on metal fluoride,fluosilicic acid alkali metal,fluoaluminic acid alkali metal and hydroxide than multihydrogen acid,fluoboric acid and mud acid systems.These research results provide a technical support for the plugging removal in hightemperature deep oil and gas reservoirs.
