Aim: To investigate the possible functions of human sperm membrane protein (hSMP-1) in the process of fertilization. Methods: A 576-bp cDNA fragment of HSD-1 gene coding for the extracellular domain of hSMP-1 was ...Aim: To investigate the possible functions of human sperm membrane protein (hSMP-1) in the process of fertilization. Methods: A 576-bp cDNA fragment of HSD-1 gene coding for the extracellular domain of hSMP-1 was cloned and expressed. The localization of this protein on human and mouse sperm was determined by indirect immunofluorescent staining by using anti-recombinant hSMP-1 (anti-rhSMP-1) antibodies. Sperm acrosome reaction and spermzona pellucida (ZP) binding assay were carried out in 10-week-old BALB/c mice. Results: Recombinant hSMP-1 was successfully cloned and expressed. The expression of the native protein was limited on the acrosome of human and mouse sperm. Treatment of anti-rhSMP-1 antibodies significantly decreased the average number of sperms bound to each egg. Meanwhile, the percentage of acrosome reaction was decreased in comparison to pre-immune control after treatment with anti-rhSMP-1 (P 〈 0.05). Conclusion: The results suggest that anti-rhSMP-1 antibody inhibited mouse acrosome reaction and sperm-ZP binding.展开更多
There is evidence showing that increased levels of oxidative stress and C-reactive protein (CRP) might be associated with obesity, hypertension, atherosclerosis and other cardiovascular diseases. This study was undert...There is evidence showing that increased levels of oxidative stress and C-reactive protein (CRP) might be associated with obesity, hypertension, atherosclerosis and other cardiovascular diseases. This study was undertaken to investigate possible relationships among plasma 8-iso-prostaglandin F2α (8-iso-PG F2α: an index of oxidative stress), high-sensitivity (hs)-CRP and membrane fluidity (a reciprocal value of microviscosity) in hypertensive and normotensive men using an electron spin resonance (ESR)-method. The order parameter (S) for the spin-label agents (5-nitroxide stearate) of red blood cell (RBC) membranes in the ESR spectra was significantly higher in hypertensive men than in normotensive men, indicating that membrane fluidity was decreased in hypertensive men. Both plasma 8-iso-PG F2α and hs-CRP levels were significantly increased in hypertensive men compared with normotensive men. In addition, plasma plasma 8-iso-PG F2α levels were correlated with plasma hs-CRP levels. In contrast, plasma nitric oxide (NO)-metabolites were lower in hypertensive men than in normotensive men, and inversely correlated with plasma 8-iso-PG F2α and hs-CRP. The order parameter(S) of RBCs was correlated with plasma 8-iso-PG F2α and plasma hs-CRP, and inversely correlated with plasma NO-metabolites, suggesting that reduced membrane fluidity of RBCs might be associated with increased oxidative stress, inflammation and endothelial dysfunction. Multivariate regression analysis also showed that, after adjusting for general risk factors, both plasma 8-iso-PG F2α and hs-CRP were significant determinants of membrane fluidity of RBCs. The ESR suggests that associations of oxidative stress and inflammation might have a close correlation with impaired rheologic behavior of RBCs and microcirculatory dysfunction in hypertensive men.展开更多
目的研究细胞膜角蛋白8(CK8)和乳腺癌耐药蛋白(breast cancer resistant protein,BCRP)作为多靶点治疗逆转耐药的可行性。方法共转染特异的CK8-siRNAs和BCRP-siRNAs至人乳腺癌多药耐药细胞MCF-7/MX,用Western blot方法检测siRNAs对CK8和...目的研究细胞膜角蛋白8(CK8)和乳腺癌耐药蛋白(breast cancer resistant protein,BCRP)作为多靶点治疗逆转耐药的可行性。方法共转染特异的CK8-siRNAs和BCRP-siRNAs至人乳腺癌多药耐药细胞MCF-7/MX,用Western blot方法检测siRNAs对CK8和BCRP蛋白表达的抑制,荧光染色用激光共聚焦显微镜观察细胞膜表面CK8表达量的变化,并用Sulforhodamine B的方法检测转染前后细胞对多种化疗药敏感性的变化。结果MCF-7/MX细胞导入CK8-siRNAs和BCRP-siRNAs后,CK8和BCRP的表达水平均明显降低,且细胞表面CK8染色也明显降低,同时对米托蒽醌等化疗药的敏感性明显提高,耐药表型明显逆转。结论CK8和BCRP在MCF-7/MX耐药细胞中共同高表达且在乳腺癌多药耐药表型的形成中起重要作用,共同抑制CK8和BCRP的表达可以有效逆转乳腺癌的多药耐药,为治疗肿瘤多药耐药提供了一条新的思路。展开更多
膜融合对真核生物的诸多生命活动至关重要,需要不同的囊泡转运蛋白互相配合,从而特异性协调并辅助不同生物膜的融合,这些囊泡转运蛋白高度保守。囊泡相关膜蛋白8(vesicle associated membrane protein 8,VAMP8)主要定位于囊泡膜和溶酶体...膜融合对真核生物的诸多生命活动至关重要,需要不同的囊泡转运蛋白互相配合,从而特异性协调并辅助不同生物膜的融合,这些囊泡转运蛋白高度保守。囊泡相关膜蛋白8(vesicle associated membrane protein 8,VAMP8)主要定位于囊泡膜和溶酶体膜,其在多种不同生物膜的融合中发挥重要作用。本文就VAMP8的分子结构、转录调控和翻译后修饰、生物学功能及其与人类疾病相关性的研究进展作一综述,以期为治疗相关疾病和开发有效的VAMP8靶点药物提供新思路。展开更多
目的:探讨囊泡相关膜蛋白8(VAMP8)在结肠癌组织中的表达及其临床意义。方法:收集42例结肠癌患者癌组织及癌旁正常组织标本,用免疫组化法检测VAMP8蛋白的阳性表达率,分析其表达与结肠癌临床病理特征之间的关系;并选择其中12对标本,用q RT...目的:探讨囊泡相关膜蛋白8(VAMP8)在结肠癌组织中的表达及其临床意义。方法:收集42例结肠癌患者癌组织及癌旁正常组织标本,用免疫组化法检测VAMP8蛋白的阳性表达率,分析其表达与结肠癌临床病理特征之间的关系;并选择其中12对标本,用q RT-PCR与Western blot法检测VAMP8 m RNA与蛋白的表达量。结果:q RT-PCR及Western blot检测显示,9对标本的结肠癌组织VAMP8 m RNA与蛋白表达量明显高于其对应的癌旁组织(均P<0.05);免疫组化结果显示,VAMP8在结肠癌组织中的阳性率明显高于癌旁组织(73.8%vs.42.9%;χ2=8.28,P<0.01),且VAMP8的表达与肿瘤的分化程度、Dukes分期及淋巴结转移情况有关(均P<0.05)。结论:VAMP8在结肠癌组织中表达上调,提示VAMP8可能通过调节自噬/溶酶体途径促进结肠癌的恶性进展与转移。展开更多
Plants produce numerous terpenes and much effort has been dedicated to the identification and charac- terization of the terpene biosynthetic genes. However, little is known about how terpenes are transported within th...Plants produce numerous terpenes and much effort has been dedicated to the identification and charac- terization of the terpene biosynthetic genes. However, little is known about how terpenes are transported within the cell and from the cell into the apoplast. To investigate a putative role of vesicle fusion in this pro- cess, we used Agrobacterium tumefaciens-mediated transient coexpression in Nicotiana benthamiana of an MtVAMP721e-RNAi construct (Vi) with either a caryophyllene synthase or a linalool synthase, respec- tively. Headspace analysis of the leaves showed that caryophyllene or linalool emission increased about five-fold when N. benthamiana VAMP72 function was blocked. RNA sequencing and protein ubiquitination analysis of the agroinflltrated N. benthamiana leaf extracts suggested that increased terpene emissions may be attributed to proteasome malfunction based on three observations: leaves with TPS+Vi showed (1) a higher level of a DsRed marker protein, (2) a higher level of ubiquitinated proteins, and (3) coordinated induced expression of multiple proteasome genes, presumably caused by the lack of proteasome- mediated feedback regulation. However, caryophyllene or linalool did not inhibit proteasome-related pro- tease activity in the in vitro assays. While the results are not conclusive for a role of vesicle fusion in terpene transport, they do show a strong interaction between inhibition of vesicle fusion and ectopic expression of certain terpenes. The results have potential applications in metabolic engineering.展开更多
文摘Aim: To investigate the possible functions of human sperm membrane protein (hSMP-1) in the process of fertilization. Methods: A 576-bp cDNA fragment of HSD-1 gene coding for the extracellular domain of hSMP-1 was cloned and expressed. The localization of this protein on human and mouse sperm was determined by indirect immunofluorescent staining by using anti-recombinant hSMP-1 (anti-rhSMP-1) antibodies. Sperm acrosome reaction and spermzona pellucida (ZP) binding assay were carried out in 10-week-old BALB/c mice. Results: Recombinant hSMP-1 was successfully cloned and expressed. The expression of the native protein was limited on the acrosome of human and mouse sperm. Treatment of anti-rhSMP-1 antibodies significantly decreased the average number of sperms bound to each egg. Meanwhile, the percentage of acrosome reaction was decreased in comparison to pre-immune control after treatment with anti-rhSMP-1 (P 〈 0.05). Conclusion: The results suggest that anti-rhSMP-1 antibody inhibited mouse acrosome reaction and sperm-ZP binding.
文摘There is evidence showing that increased levels of oxidative stress and C-reactive protein (CRP) might be associated with obesity, hypertension, atherosclerosis and other cardiovascular diseases. This study was undertaken to investigate possible relationships among plasma 8-iso-prostaglandin F2α (8-iso-PG F2α: an index of oxidative stress), high-sensitivity (hs)-CRP and membrane fluidity (a reciprocal value of microviscosity) in hypertensive and normotensive men using an electron spin resonance (ESR)-method. The order parameter (S) for the spin-label agents (5-nitroxide stearate) of red blood cell (RBC) membranes in the ESR spectra was significantly higher in hypertensive men than in normotensive men, indicating that membrane fluidity was decreased in hypertensive men. Both plasma 8-iso-PG F2α and hs-CRP levels were significantly increased in hypertensive men compared with normotensive men. In addition, plasma plasma 8-iso-PG F2α levels were correlated with plasma hs-CRP levels. In contrast, plasma nitric oxide (NO)-metabolites were lower in hypertensive men than in normotensive men, and inversely correlated with plasma 8-iso-PG F2α and hs-CRP. The order parameter(S) of RBCs was correlated with plasma 8-iso-PG F2α and plasma hs-CRP, and inversely correlated with plasma NO-metabolites, suggesting that reduced membrane fluidity of RBCs might be associated with increased oxidative stress, inflammation and endothelial dysfunction. Multivariate regression analysis also showed that, after adjusting for general risk factors, both plasma 8-iso-PG F2α and hs-CRP were significant determinants of membrane fluidity of RBCs. The ESR suggests that associations of oxidative stress and inflammation might have a close correlation with impaired rheologic behavior of RBCs and microcirculatory dysfunction in hypertensive men.
文摘膜融合对真核生物的诸多生命活动至关重要,需要不同的囊泡转运蛋白互相配合,从而特异性协调并辅助不同生物膜的融合,这些囊泡转运蛋白高度保守。囊泡相关膜蛋白8(vesicle associated membrane protein 8,VAMP8)主要定位于囊泡膜和溶酶体膜,其在多种不同生物膜的融合中发挥重要作用。本文就VAMP8的分子结构、转录调控和翻译后修饰、生物学功能及其与人类疾病相关性的研究进展作一综述,以期为治疗相关疾病和开发有效的VAMP8靶点药物提供新思路。
文摘目的:探讨囊泡相关膜蛋白8(VAMP8)在结肠癌组织中的表达及其临床意义。方法:收集42例结肠癌患者癌组织及癌旁正常组织标本,用免疫组化法检测VAMP8蛋白的阳性表达率,分析其表达与结肠癌临床病理特征之间的关系;并选择其中12对标本,用q RT-PCR与Western blot法检测VAMP8 m RNA与蛋白的表达量。结果:q RT-PCR及Western blot检测显示,9对标本的结肠癌组织VAMP8 m RNA与蛋白表达量明显高于其对应的癌旁组织(均P<0.05);免疫组化结果显示,VAMP8在结肠癌组织中的阳性率明显高于癌旁组织(73.8%vs.42.9%;χ2=8.28,P<0.01),且VAMP8的表达与肿瘤的分化程度、Dukes分期及淋巴结转移情况有关(均P<0.05)。结论:VAMP8在结肠癌组织中表达上调,提示VAMP8可能通过调节自噬/溶酶体途径促进结肠癌的恶性进展与转移。
文摘Plants produce numerous terpenes and much effort has been dedicated to the identification and charac- terization of the terpene biosynthetic genes. However, little is known about how terpenes are transported within the cell and from the cell into the apoplast. To investigate a putative role of vesicle fusion in this pro- cess, we used Agrobacterium tumefaciens-mediated transient coexpression in Nicotiana benthamiana of an MtVAMP721e-RNAi construct (Vi) with either a caryophyllene synthase or a linalool synthase, respec- tively. Headspace analysis of the leaves showed that caryophyllene or linalool emission increased about five-fold when N. benthamiana VAMP72 function was blocked. RNA sequencing and protein ubiquitination analysis of the agroinflltrated N. benthamiana leaf extracts suggested that increased terpene emissions may be attributed to proteasome malfunction based on three observations: leaves with TPS+Vi showed (1) a higher level of a DsRed marker protein, (2) a higher level of ubiquitinated proteins, and (3) coordinated induced expression of multiple proteasome genes, presumably caused by the lack of proteasome- mediated feedback regulation. However, caryophyllene or linalool did not inhibit proteasome-related pro- tease activity in the in vitro assays. While the results are not conclusive for a role of vesicle fusion in terpene transport, they do show a strong interaction between inhibition of vesicle fusion and ectopic expression of certain terpenes. The results have potential applications in metabolic engineering.