Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at th...Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.展开更多
Previous report showed that the 209 bp DNA sequence upstream of the sericin 1 transcriptional start site （-586 to -378 bp） is involved in promoting transcription and responsible for the tissue specificity of sericin...Previous report showed that the 209 bp DNA sequence upstream of the sericin 1 transcriptional start site （-586 to -378 bp） is involved in promoting transcription and responsible for the tissue specificity of sericin 1 promoter in silkworm Bombyx mori. In the present study, this 209 bp sequence exhibited enhancive effect by assembling in two different locations of ubiquitous Bombyx A3 cytoplasmic actin promoter. Sf-9 cells were transfected with recombinant plasmids using Cellfectin reagent. Firefly luciferase gene located downstream of fusion promoter was considered as a reporter, whereas the activity of the co-transfected Renilla luciferase gene （pGL2-SV40） provides an internal control. This 209 bp region up-regulates the strength of A3 promoter significantly （P〈0.01） when it enters into A3 promoter with respect to the position in sericin 1 gene promoter. This 209-bp fragment was almost functionless when being located upstream of A3 promoter.展开更多
Studies have found that the phosphatase actin regulatory factor 1 expression can be related to stroke,but it remains unclear whether changes in phosphatase actin regulatory factor 1 expression also play a role in trau...Studies have found that the phosphatase actin regulatory factor 1 expression can be related to stroke,but it remains unclear whether changes in phosphatase actin regulatory factor 1 expression also play a role in traumatic brain injury.In this study we found that,in a mouse model of traumatic brain injury induced by controlled cortical impact,phosphatase actin regulatory factor 1 expression is increased in endothelial cells,neurons,astrocytes,and microglia.When we overexpressed phosphatase actin regulatory factor 1 by injection an adeno-associated virus vector into the contused area in the traumatic brain injury mice,the water content of the brain tissue increased.However,when phosphatase actin regulatory factor 1 was knocked down,the water content decreased.We also found that inhibiting phosphatase actin regulatory factor 1 expression regulated the nuclear factor kappa B signaling pathway,decreased blood-brain barrier permeability,reduced aquaporin 4 and intercellular adhesion molecule 1 expression,inhibited neuroinflammation,and neuronal apoptosis,thereby improving neurological function.The findings from this study indicate that phosphatase actin regulatory factor 1 may be a potential therapeutic target for traumatic brain injury.展开更多
Cardiotrophin-1 （CT-1） activates a distinct form of cardiac muscle cell hypertrophy in which the sarcomeric units are assembled in series. The aim of the study was to determine the expres- sion pattern of sarcomeric...Cardiotrophin-1 （CT-1） activates a distinct form of cardiac muscle cell hypertrophy in which the sarcomeric units are assembled in series. The aim of the study was to determine the expres- sion pattern of sarcomeric contractile protein α-actin, specialized eytoskeletal protein α-actinin and mitochondrial uncoupling protein-2 （UCP2） in myocardial remodeling induced by chronic exposure to CT-1. Kunming mice were intraperitoneally injected with carboxy-terminal polypeptide （CP） of CT-1 （CT-1-CP, 500 μg·kg-1·day^-1） for 1, 2, 3 and 4 week （s）, respectively （4 groups obtained according to the injection time, n=10 each, with 5 males and 5 females in each group）, Those injected with physiological saline for 4 weeks served as controls （n=10, with 5 males and 5 females）. The heart tissues of mice were harvested at 1, 2, 3 or 4 week （s）. Immunohistochemistry （IHC） and Western blotting （WB） were used to detect the distribution and expression of sarcomeric α-actin, α-aetinin and mitoehondrial UCP2 in myocardial tissues. IHC showed that α-actin was mainly distributed around the nuclei of cardiomyo- cytes, α-actinin concentrated around the striae and UCP2 scattered rather evenly in the plasma. The ex- pression of α-actin was slightly greater than that of α-actinin and UCP2 in the control group （IHC： χ^2=6.125; WB： F=0.249, P〉0.05） and it gradually decreased after exposure to CT-1-CP. There was no significant difference in the expression of α-actin between the control group and the CT-1-CP-treated groups （χ^2=7.386, P〉0.05）. But Western blotting revealed significant difference in the expression of α-actin between the control group and the 4-week CT-1-CP-treated group （F=2.912; q=4.203, P〈0.05）. Moreover, it was found that the expression of α-actinin increased stepwise with the exposure time in CT-1-CP-treated groups and differed significantly between CT-1-CP-treated groups and the control group （ICH： χ^2=21.977; WB： F=50.388; P〈0.01）. The expression of UCP2 was initially increased （WB： control group vs. 1- or 2-week group, q values： 5.603 and 9.995, respectively, P〈0.01） and then de- creased （WB： control group vs. 3-week group, q=4.742, P〈0.01; control group vs. 4-week group, q=0.558, P〉0.05）. It was suggested that long-term exposure to CT-1-CP could lead to the alteration in the expression of sarcomeric α-actin, α-actinin and mitochonclrial UCP2. The different expressions of sarcomeric structure proteins and mitochondrial UCP2 may be involved in myocardial remodeling.展开更多
Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle tissues.Multiple genes encoding muscle actin have been identified from the ...Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle tissues.Multiple genes encoding muscle actin have been identified from the ascidians,including those expressed in the larval tail muscle,the adult body-wall muscle,and adult heart muscle.In this study,a novel striated non-tail muscle actin gene was identified from the RNA-seq data of Ciona savignyi embryos.Phylogenetic analysis,alignment of the N-terminal amino acid sequences and comparation of diagnostic residues provided evidence that it had high similarity with vertebrate cardiac and skeletal muscle actin.In situ hybridization and promoter-driven GFP reporter assay revealed that it was specifically expressed in the primordia of the oral and atrial siphon.We hereby defined it as siphon-specific muscle actin coding gene(Cs-SMA).A 201 bp(−1350 bp to−1150 bp)sequence containing T-box and Six1/2 binding motif within the upstream region of Cs-SMA confined the expression of GFP in the siphons of electroporated embryos.Six1/2 binding motif was experimentally confirmed to play indispensable role in controlling the siphon-specific expression of Cs-SMA.The tissue-specific expression of Cs-SMA in the siphon primordia indicated its potential crucial roles in Ciona embryogenesis and organogenesis.展开更多
目的探讨血管紧张素(1-7)[Ang-(1-7)]对胆管结扎(BDL)大鼠肝纤维化的抑制作用。方法 18只Wister雄性大鼠随机分为假手术(SHAME组)组,BDL组和Ang-(1-7)治疗组。假手术组:行开腹术再关腹,在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射...目的探讨血管紧张素(1-7)[Ang-(1-7)]对胆管结扎(BDL)大鼠肝纤维化的抑制作用。方法 18只Wister雄性大鼠随机分为假手术(SHAME组)组,BDL组和Ang-(1-7)治疗组。假手术组:行开腹术再关腹,在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射生理盐水;BDL组:开腹结扎胆总管建立肝纤维化模型,在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射生理盐水;Ang-(1-7)治疗组:BDL建立肝纤维化模型,同时在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射Ang-(1-7)。4周后宰杀动物、取肝组织,行Masson胶原染色,肝纤维化评分,测定羟脯氨酸含量,免疫组织化学检测α-肌动蛋白(α-SMA)的表达。结果与BDL组相比,Ang-(1-7)治疗组肝纤维化评分(2.33±0.52 vs 5.17±0.75)、胶原面积(23.71±3.43 vs 89.77±9.92)、羟脯氨酸含量(0.36±0.03 vs 0.52±0.04)、α-SMA的表达(54.11±17.55 vs 191.84±31.72)均减少,有统计学意义(P<0.01)。结论Ang-(1-7)对胆总管结扎所致的肝纤维化具有抑制作用。展开更多
基金supported by the National Key Research and Development Program of China,No.2021ZD0202503(to AHT)the National Natural Science Foundation of China,Nos.31872759(to AHT)and 32070707(to CF)+1 种基金Shenzhen Science and Technology Program,No.RCJC20210609104333007(to ZW)Shenzhen-Hong Kong Institute of Brain Science,Shenzhen Fundamental Research Institutions,No.2021SHIBS0002(to ZW).
文摘Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.
基金the National Natural Science Foundation of China(30470350)the National High Technology Research and Development Program of China(863 Program,2006AA10A119).
文摘Previous report showed that the 209 bp DNA sequence upstream of the sericin 1 transcriptional start site （-586 to -378 bp） is involved in promoting transcription and responsible for the tissue specificity of sericin 1 promoter in silkworm Bombyx mori. In the present study, this 209 bp sequence exhibited enhancive effect by assembling in two different locations of ubiquitous Bombyx A3 cytoplasmic actin promoter. Sf-9 cells were transfected with recombinant plasmids using Cellfectin reagent. Firefly luciferase gene located downstream of fusion promoter was considered as a reporter, whereas the activity of the co-transfected Renilla luciferase gene （pGL2-SV40） provides an internal control. This 209 bp region up-regulates the strength of A3 promoter significantly （P〈0.01） when it enters into A3 promoter with respect to the position in sericin 1 gene promoter. This 209-bp fragment was almost functionless when being located upstream of A3 promoter.
基金supported by the National Natural Science Foundation of China,Nos.81501048(to JD),81801236(to ZMX),81974189(to HLT)Shanghai 6th People’s Hospital Research Fund,No.ynlc201808(to JD).
文摘Studies have found that the phosphatase actin regulatory factor 1 expression can be related to stroke,but it remains unclear whether changes in phosphatase actin regulatory factor 1 expression also play a role in traumatic brain injury.In this study we found that,in a mouse model of traumatic brain injury induced by controlled cortical impact,phosphatase actin regulatory factor 1 expression is increased in endothelial cells,neurons,astrocytes,and microglia.When we overexpressed phosphatase actin regulatory factor 1 by injection an adeno-associated virus vector into the contused area in the traumatic brain injury mice,the water content of the brain tissue increased.However,when phosphatase actin regulatory factor 1 was knocked down,the water content decreased.We also found that inhibiting phosphatase actin regulatory factor 1 expression regulated the nuclear factor kappa B signaling pathway,decreased blood-brain barrier permeability,reduced aquaporin 4 and intercellular adhesion molecule 1 expression,inhibited neuroinflammation,and neuronal apoptosis,thereby improving neurological function.The findings from this study indicate that phosphatase actin regulatory factor 1 may be a potential therapeutic target for traumatic brain injury.
文摘Cardiotrophin-1 （CT-1） activates a distinct form of cardiac muscle cell hypertrophy in which the sarcomeric units are assembled in series. The aim of the study was to determine the expres- sion pattern of sarcomeric contractile protein α-actin, specialized eytoskeletal protein α-actinin and mitochondrial uncoupling protein-2 （UCP2） in myocardial remodeling induced by chronic exposure to CT-1. Kunming mice were intraperitoneally injected with carboxy-terminal polypeptide （CP） of CT-1 （CT-1-CP, 500 μg·kg-1·day^-1） for 1, 2, 3 and 4 week （s）, respectively （4 groups obtained according to the injection time, n=10 each, with 5 males and 5 females in each group）, Those injected with physiological saline for 4 weeks served as controls （n=10, with 5 males and 5 females）. The heart tissues of mice were harvested at 1, 2, 3 or 4 week （s）. Immunohistochemistry （IHC） and Western blotting （WB） were used to detect the distribution and expression of sarcomeric α-actin, α-aetinin and mitoehondrial UCP2 in myocardial tissues. IHC showed that α-actin was mainly distributed around the nuclei of cardiomyo- cytes, α-actinin concentrated around the striae and UCP2 scattered rather evenly in the plasma. The ex- pression of α-actin was slightly greater than that of α-actinin and UCP2 in the control group （IHC： χ^2=6.125; WB： F=0.249, P〉0.05） and it gradually decreased after exposure to CT-1-CP. There was no significant difference in the expression of α-actin between the control group and the CT-1-CP-treated groups （χ^2=7.386, P〉0.05）. But Western blotting revealed significant difference in the expression of α-actin between the control group and the 4-week CT-1-CP-treated group （F=2.912; q=4.203, P〈0.05）. Moreover, it was found that the expression of α-actinin increased stepwise with the exposure time in CT-1-CP-treated groups and differed significantly between CT-1-CP-treated groups and the control group （ICH： χ^2=21.977; WB： F=50.388; P〈0.01）. The expression of UCP2 was initially increased （WB： control group vs. 1- or 2-week group, q values： 5.603 and 9.995, respectively, P〈0.01） and then de- creased （WB： control group vs. 3-week group, q=4.742, P〈0.01; control group vs. 4-week group, q=0.558, P〉0.05）. It was suggested that long-term exposure to CT-1-CP could lead to the alteration in the expression of sarcomeric α-actin, α-actinin and mitochonclrial UCP2. The different expressions of sarcomeric structure proteins and mitochondrial UCP2 may be involved in myocardial remodeling.
基金funded by the National Key Research and Development Program of China(Nos.2019YFE0190900,2018YFD0900705).
文摘Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle tissues.Multiple genes encoding muscle actin have been identified from the ascidians,including those expressed in the larval tail muscle,the adult body-wall muscle,and adult heart muscle.In this study,a novel striated non-tail muscle actin gene was identified from the RNA-seq data of Ciona savignyi embryos.Phylogenetic analysis,alignment of the N-terminal amino acid sequences and comparation of diagnostic residues provided evidence that it had high similarity with vertebrate cardiac and skeletal muscle actin.In situ hybridization and promoter-driven GFP reporter assay revealed that it was specifically expressed in the primordia of the oral and atrial siphon.We hereby defined it as siphon-specific muscle actin coding gene(Cs-SMA).A 201 bp(−1350 bp to−1150 bp)sequence containing T-box and Six1/2 binding motif within the upstream region of Cs-SMA confined the expression of GFP in the siphons of electroporated embryos.Six1/2 binding motif was experimentally confirmed to play indispensable role in controlling the siphon-specific expression of Cs-SMA.The tissue-specific expression of Cs-SMA in the siphon primordia indicated its potential crucial roles in Ciona embryogenesis and organogenesis.
文摘目的探讨血管紧张素(1-7)[Ang-(1-7)]对胆管结扎(BDL)大鼠肝纤维化的抑制作用。方法 18只Wister雄性大鼠随机分为假手术(SHAME组)组,BDL组和Ang-(1-7)治疗组。假手术组:行开腹术再关腹,在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射生理盐水;BDL组:开腹结扎胆总管建立肝纤维化模型,在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射生理盐水;Ang-(1-7)治疗组:BDL建立肝纤维化模型,同时在腹腔埋注射泵,以25μg.kg-1.h-1的速度持续注射Ang-(1-7)。4周后宰杀动物、取肝组织,行Masson胶原染色,肝纤维化评分,测定羟脯氨酸含量,免疫组织化学检测α-肌动蛋白(α-SMA)的表达。结果与BDL组相比,Ang-(1-7)治疗组肝纤维化评分(2.33±0.52 vs 5.17±0.75)、胶原面积(23.71±3.43 vs 89.77±9.92)、羟脯氨酸含量(0.36±0.03 vs 0.52±0.04)、α-SMA的表达(54.11±17.55 vs 191.84±31.72)均减少,有统计学意义(P<0.01)。结论Ang-(1-7)对胆总管结扎所致的肝纤维化具有抑制作用。
