Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitativ...Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitative Western±Blot technique was developed using anti±TRF1^33±277 monoclonal antibody and GST±TRFI purity protein as a standard to further determine the expression level of TRF1 protein in total proteins extracted from clinical specimens. Results: Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors' bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher (P〈0.01) in normal bone marrow ((2.2174±0.462) μg/μl) than that of acute leukemia patients ((0.7544±0.343) μg/μl), But there was no remarkable difference between ALL and ANLL patients ((0.6184±0.285) μg/μl vs (0.8454±0.359) μg/μl, P〉0.05). After chemotherapy, TRFI expression level of patients with complete remission elevated ((0.7724±0.307)/μg/μl vs (1.6834±0,344)μg/μl, P〈0.01 ), but lower than that of normal ((2.2174±0.462)/μg/μl, P〈0.01). There was no significantly difference after chemotherapy ((0.7264±0.411) μg/μl vs (0.895±0.339) μg/μl,p〉0.05). TRF1 expression level of patients with complete remission is higher than that of patients without complete remission ((1,683±0.344)μg/μl vs (0.895±0.339)μg/μl P〈0.01). All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients ((0.125±0.078) μg/μl vs (0.765±0.284)μg/μl, P〈0.01). There was no significant difference of expression level ofTRF I protein between ALL and ANLL patients ((0.897±0.290) μg/μl vs (0.677±0.268) μg/μl, P〉0.05). After chemotherapy, telomerase activity of patients with complete remission decreased ((0.393±0.125) μg/μl), but was still higher than that of normal ((0.125±0.078) μg/μl, P〈0.01). Conclusion: The expression level of TRF1 protein has correlativity to the activity of telomerase (P〈0.001).展开更多
Objective: To express human telomeric repeat binding factor (TRF1) at high level in E. coli. Method: Two primers were designed with Kpn I and EcoR I sites respectively, TRF1 cDNA fragments was amplified and cloned int...Objective: To express human telomeric repeat binding factor (TRF1) at high level in E. coli. Method: Two primers were designed with Kpn I and EcoR I sites respectively, TRF1 cDNA fragments was amplified and cloned into plasmid pET29α, each step was confirmed by sequencing and restriction endonuclease map analysis. And the recombinant plasmid pET29α-TRFl was then transformed into E. coli BL21 (DE3) PlysS. Fusion protein was purified by S-protein Kit and checked by SDS-PAGE and by western blot. Result: E. coli BL21 (DE3) PlysS expressing high level of 30 KD partial TRF1 was obtained, and TRF1 fusion protein was purified. The optimal induction time was at 2.5 h. Excessive expression system was established and 18.6% inductive protein was obtained. Conclusion: The expressed protein can be used for producing both polyclonal and monoclonal antibodies and for further study of the function and structure of TRF1 and its association with malignant tumor and leukemia.展开更多
文摘Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitative Western±Blot technique was developed using anti±TRF1^33±277 monoclonal antibody and GST±TRFI purity protein as a standard to further determine the expression level of TRF1 protein in total proteins extracted from clinical specimens. Results: Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors' bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher (P〈0.01) in normal bone marrow ((2.2174±0.462) μg/μl) than that of acute leukemia patients ((0.7544±0.343) μg/μl), But there was no remarkable difference between ALL and ANLL patients ((0.6184±0.285) μg/μl vs (0.8454±0.359) μg/μl, P〉0.05). After chemotherapy, TRFI expression level of patients with complete remission elevated ((0.7724±0.307)/μg/μl vs (1.6834±0,344)μg/μl, P〈0.01 ), but lower than that of normal ((2.2174±0.462)/μg/μl, P〈0.01). There was no significantly difference after chemotherapy ((0.7264±0.411) μg/μl vs (0.895±0.339) μg/μl,p〉0.05). TRF1 expression level of patients with complete remission is higher than that of patients without complete remission ((1,683±0.344)μg/μl vs (0.895±0.339)μg/μl P〈0.01). All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients ((0.125±0.078) μg/μl vs (0.765±0.284)μg/μl, P〈0.01). There was no significant difference of expression level ofTRF I protein between ALL and ANLL patients ((0.897±0.290) μg/μl vs (0.677±0.268) μg/μl, P〉0.05). After chemotherapy, telomerase activity of patients with complete remission decreased ((0.393±0.125) μg/μl), but was still higher than that of normal ((0.125±0.078) μg/μl, P〈0.01). Conclusion: The expression level of TRF1 protein has correlativity to the activity of telomerase (P〈0.001).
基金the National Natural Science Foundation of China (No. 39870339).
文摘Objective: To express human telomeric repeat binding factor (TRF1) at high level in E. coli. Method: Two primers were designed with Kpn I and EcoR I sites respectively, TRF1 cDNA fragments was amplified and cloned into plasmid pET29α, each step was confirmed by sequencing and restriction endonuclease map analysis. And the recombinant plasmid pET29α-TRFl was then transformed into E. coli BL21 (DE3) PlysS. Fusion protein was purified by S-protein Kit and checked by SDS-PAGE and by western blot. Result: E. coli BL21 (DE3) PlysS expressing high level of 30 KD partial TRF1 was obtained, and TRF1 fusion protein was purified. The optimal induction time was at 2.5 h. Excessive expression system was established and 18.6% inductive protein was obtained. Conclusion: The expressed protein can be used for producing both polyclonal and monoclonal antibodies and for further study of the function and structure of TRF1 and its association with malignant tumor and leukemia.