A novel ribosome-inactivating protein designated Moschatin from the mature seeds of pumpkin (Cucurbita moschata) has been successively purified to homogeneity, using ammonium sulfate precipitation, CM-cellulose 52 col...A novel ribosome-inactivating protein designated Moschatin from the mature seeds of pumpkin (Cucurbita moschata) has been successively purified to homogeneity, using ammonium sulfate precipitation, CM-cellulose 52 column chromatography, Blue Sepharose CL-6B Affinity column chromatography and FPLC size-exclusion column chromatography. Moschatin is a type 1 RIP with a pI of 9.4 and molecular weight of~29 kD. It is a rRNA N-glycosidase and potently blocked the protein synthesis in the rabbit reticulocyte lysate with a IC_(50) of 0.26 nM. Using the anti-human melanoma McAb Ng76, a novel immunotoxin Moschatin-Ng76 was prepared successfully and it efficiently inhibited the growth of targeted melanoma cells M_(21) with a IC_(50) of 0.04 nM, 1500 times lower than that of free Moschatin. The results implied that Moschatin could be used as a new potential anticancer agent.展开更多
Ribosome-inactivating proteins(RIPs) belong to a family of enzymes that attack eukaryotic ribosomes and potently inhibit cellular protein synthesis.RIPs possess several biomedical properties,including anti-viral and a...Ribosome-inactivating proteins(RIPs) belong to a family of enzymes that attack eukaryotic ribosomes and potently inhibit cellular protein synthesis.RIPs possess several biomedical properties,including anti-viral and anti-tumor activities.Multiple RIPs are known to inhibit tumor cell proliferation through inducing apoptosis in a variety of cancers,such as breast cancer,leukemia/lymphoma,and hepatoma.This review focuses on the anti-tumor activities of RIPs and their apoptotic effects through three closely related pathways:mitochondrial,death receptor,and endoplasmic reticulum pathways.展开更多
核糖体失活蛋白(ribosome-inactivating proteins,RIPs)是一类能够脱去真核细胞28S r RNA内SRL区域的A4342,从而破坏延伸因子与核糖体的结合,将蛋白质的生物合成抑制在延伸阶段的蛋白质家族。RIPs有Ⅰ、Ⅱ、Ⅲ型,苦瓜中已发现的α-苦瓜...核糖体失活蛋白(ribosome-inactivating proteins,RIPs)是一类能够脱去真核细胞28S r RNA内SRL区域的A4342,从而破坏延伸因子与核糖体的结合,将蛋白质的生物合成抑制在延伸阶段的蛋白质家族。RIPs有Ⅰ、Ⅱ、Ⅲ型,苦瓜中已发现的α-苦瓜素、β-苦瓜素、γ-苦瓜素、δ-苦瓜素、ε-苦瓜素、MAP30等,均属于Ⅰ型RIPs。这些RIPs具有抗病毒、抗菌、抗虫害、抑制肿瘤细胞生长等生物学活性,受到了人们的广泛关注。本文从RIPs的分类、生物学活性、功能与应用等方面,对苦瓜中的RIPs进行了综述。展开更多
文摘A novel ribosome-inactivating protein designated Moschatin from the mature seeds of pumpkin (Cucurbita moschata) has been successively purified to homogeneity, using ammonium sulfate precipitation, CM-cellulose 52 column chromatography, Blue Sepharose CL-6B Affinity column chromatography and FPLC size-exclusion column chromatography. Moschatin is a type 1 RIP with a pI of 9.4 and molecular weight of~29 kD. It is a rRNA N-glycosidase and potently blocked the protein synthesis in the rabbit reticulocyte lysate with a IC_(50) of 0.26 nM. Using the anti-human melanoma McAb Ng76, a novel immunotoxin Moschatin-Ng76 was prepared successfully and it efficiently inhibited the growth of targeted melanoma cells M_(21) with a IC_(50) of 0.04 nM, 1500 times lower than that of free Moschatin. The results implied that Moschatin could be used as a new potential anticancer agent.
基金the Basic Research Program of Shenzhen(JCYJ20120613113228732)the University Innovation Program of Guangdong Province (201410590040)
文摘Ribosome-inactivating proteins(RIPs) belong to a family of enzymes that attack eukaryotic ribosomes and potently inhibit cellular protein synthesis.RIPs possess several biomedical properties,including anti-viral and anti-tumor activities.Multiple RIPs are known to inhibit tumor cell proliferation through inducing apoptosis in a variety of cancers,such as breast cancer,leukemia/lymphoma,and hepatoma.This review focuses on the anti-tumor activities of RIPs and their apoptotic effects through three closely related pathways:mitochondrial,death receptor,and endoplasmic reticulum pathways.
文摘核糖体失活蛋白(ribosome-inactivating proteins,RIPs)是一类能够脱去真核细胞28S r RNA内SRL区域的A4342,从而破坏延伸因子与核糖体的结合,将蛋白质的生物合成抑制在延伸阶段的蛋白质家族。RIPs有Ⅰ、Ⅱ、Ⅲ型,苦瓜中已发现的α-苦瓜素、β-苦瓜素、γ-苦瓜素、δ-苦瓜素、ε-苦瓜素、MAP30等,均属于Ⅰ型RIPs。这些RIPs具有抗病毒、抗菌、抗虫害、抑制肿瘤细胞生长等生物学活性,受到了人们的广泛关注。本文从RIPs的分类、生物学活性、功能与应用等方面,对苦瓜中的RIPs进行了综述。
