A membrane-bound protein was purified from rat liver mitochondria.After being di-gested with V8 protease,two peptides containing identical 14 amino acid residue sequences were obtained.Using the 14 amino acid peptide ...A membrane-bound protein was purified from rat liver mitochondria.After being di-gested with V8 protease,two peptides containing identical 14 amino acid residue sequences were obtained.Using the 14 amino acid peptide derived DNA sequence as gene specific primer,the cDNA of correspondent gene 5′-terminal and 3′-terminal were obtained by RACE technique.The full-length cDNA that encoded a protein of 616 amino acids was thus cloned,which included the above mentioned peptide sequence.The full length cDNA was highly homologous to that of human ETF-QO,indicating that it may be the cDNA of rat ETF-QO.ETF-QO is an iron sulfur protein located in mitochondria inner membrane containing two kinds of redox center:FAD and[4Fe-4S]center.After comparing the sequence from the cDNA of the 616 amino acids protein with that of the mature protein of rat liver mitochondria,it was found that the N terminal 32 amino acid residues did not exist in the mature protein,indicating that the cDNA was that of ETF-QOp.When the cDNA was expressed in Saccharomyces cerevisiae with inducible vectors,the protein product was enriched in mitochondrial fraction and exhibited electron transfer activity(NBT re-ductase activity)of ETF-QO.Results demonstrated that the 32 amino acid peptide was a mito-chondrial targeting peptide,and both FAD and iron-sulfur cluster were inserted properly into the expressed ETF-QO.ETF-QO had a high level expression in rat heart,liver and kidney.The fu-sion protein of GFP-ETF-QO co-localized with mitochondria in COS-7 cells.展开更多
By scanning and transmission electron microscopy, leukemlc celb were obwrved after CFU-Mix culture. Even though granulocytlc growth factor, erythropoietin and lymphocytlc growth factor were added at vitor, acute leuke...By scanning and transmission electron microscopy, leukemlc celb were obwrved after CFU-Mix culture. Even though granulocytlc growth factor, erythropoietin and lymphocytlc growth factor were added at vitor, acute leukemlc celb still showed defects In differentiation and maturation. These were characterized by abnormal colony which consisted of smooth cells, bizarre shape, nuclear-cytoplasmic asynchrony In development, and appearance of nuclear bleb. However, chronic myelogenous leukemlc celb were more nature than the acute ones, manifesting in normal colony with finger- like projections and ruffled membrane. Macrophages and eosinophils could be observed. It b suggested that there b a difference In differentiation between acute and chronic leukemia cells.展开更多
基金This project was supported by the Knowledge Innovation Program of the Chinese Academy of Sciences.
文摘A membrane-bound protein was purified from rat liver mitochondria.After being di-gested with V8 protease,two peptides containing identical 14 amino acid residue sequences were obtained.Using the 14 amino acid peptide derived DNA sequence as gene specific primer,the cDNA of correspondent gene 5′-terminal and 3′-terminal were obtained by RACE technique.The full-length cDNA that encoded a protein of 616 amino acids was thus cloned,which included the above mentioned peptide sequence.The full length cDNA was highly homologous to that of human ETF-QO,indicating that it may be the cDNA of rat ETF-QO.ETF-QO is an iron sulfur protein located in mitochondria inner membrane containing two kinds of redox center:FAD and[4Fe-4S]center.After comparing the sequence from the cDNA of the 616 amino acids protein with that of the mature protein of rat liver mitochondria,it was found that the N terminal 32 amino acid residues did not exist in the mature protein,indicating that the cDNA was that of ETF-QOp.When the cDNA was expressed in Saccharomyces cerevisiae with inducible vectors,the protein product was enriched in mitochondrial fraction and exhibited electron transfer activity(NBT re-ductase activity)of ETF-QO.Results demonstrated that the 32 amino acid peptide was a mito-chondrial targeting peptide,and both FAD and iron-sulfur cluster were inserted properly into the expressed ETF-QO.ETF-QO had a high level expression in rat heart,liver and kidney.The fu-sion protein of GFP-ETF-QO co-localized with mitochondria in COS-7 cells.
文摘By scanning and transmission electron microscopy, leukemlc celb were obwrved after CFU-Mix culture. Even though granulocytlc growth factor, erythropoietin and lymphocytlc growth factor were added at vitor, acute leukemlc celb still showed defects In differentiation and maturation. These were characterized by abnormal colony which consisted of smooth cells, bizarre shape, nuclear-cytoplasmic asynchrony In development, and appearance of nuclear bleb. However, chronic myelogenous leukemlc celb were more nature than the acute ones, manifesting in normal colony with finger- like projections and ruffled membrane. Macrophages and eosinophils could be observed. It b suggested that there b a difference In differentiation between acute and chronic leukemia cells.
