RESUMO
In vitro transcription systems with T7 RNA polymerase (T7 RNAP) were widely used in preparation of RNA because of their simplicity and high efficiency. The transcripts would have additional 5' sequence since T7 promoter spans the transcription start site, while deletion of the transcription start site would severely reduce the T7 RNAP transcriptional activity. We successfully developed an in vitro transcription by combining of T7 RNAP high efficient transcription system and highly specific self-splicing technology of ribozymes, in this system, ribozyme self-splices at the designed specific site and releases the aim RNA without affecting transcription efficiency of T7 RNAP, the aminoacylation activity of human mitochondrial tRNA(Trp) (HmtRNA(Trp) (UCA)) is 113.6 pmol/microg. This method with its high efficiency on transcription and good repeatability is very suitable for preparation of accurate RNA in large scale.
Assuntos
Humanos , Sequência de Bases , RNA Polimerases Dirigidas por DNA , Genética , Dados de Sequência Molecular , RNA , Genética , Splicing de RNA , RNA Catalítico , Genética , RNA de Transferência de Triptofano , Genética , Transcrição Gênica , Aminoacilação de RNA de Transferência , Genética , Proteínas Virais , GenéticaRESUMO
Objective:To study the effects of soybean phospholipids on learning and memory abilities and contents of fatty acids in hippocampus of mice and its mechanism. Method:Mice were randomly divided into four groups:low dose(2.5g/kg) ,middle dose(5.0g/kg) and high dose(10.0g/kg) groups of soybean phospholipids and control group. The treatment groups were fed with soybean phospholipids every day while the control group with distilled water for 30 d.After learning and memory abilities were measured,the mice were killed and contents of fatty acids in hippocampus of mice were determined by high performance liquid chromatography(HPLC) . Results:(1) The learning and memory abilities of mice in middle and high dose groups were significantly improved,but only memory abilities in low dose groups were stronger than control group.(2) The contents of protein in hippocampus in middle and high dose groups were increased extremely.(3) The contents of oleic acid(C18:1) and docosahexaenoic acid(DHA,C22:6 ) were obviously enhanced in hippocampus of high dose group;but decreased in eicosapentaenoic acid(EPA,C20:5) and linoleic acid(C18:2) . The content of DHA was increased and EPA decreased significantly in middle dose group.The increase of arachidonic acid(C20:4) was not significant.Conclusion:Soybean phospholipids may improve learning and memory abilities,which might contribute to change of fatty acids contents in hippocampus of mice.
RESUMO
Objective: To study the effects of soybean phospholipids on fatty acids and phospholipids content in erythrocyte membranes of mice. Methods:The mice were fed with soybean phospholipids of 2 . 5, 5 . 0 , 10.0 g/kg bw respectively while control group with distilled water for 30 days. Then the mice were killed and contents of fatty acids and phospholipids in erythrocyte membranes were detected by HPLC. Results: (1)The contents of linoleic acid (C18 ∶2) and linolenic acid ( C18 ∶3), the composition of polyunsaturated fatty acid (PUFA) were increased obviously (P