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Transthyretin(TTR) gene was highly expressed in normal liver and it has been found to be deleted in part of DNA samples from human hepatic cancer.Its mRNA expression was suppressed in most hepatoma samples.In order to study the biological effect of TTR gene on the growth of hepatoma cells,a recombinant vector containing TTR cDNA was constructed by pCMV,then it was transfected into hepatoma cell lines SMMC-7721 and Q3.It has been demonstrated that the inhibition of growth rate of TTR cDNA transfected hepatoma cells was about 50% in strength compared with that of the control.This inhibition was further enhanced when the transfected hepatoma cells were treated with all-trans retinoic acid.Hepatoma cells of cell lines PLC/PRF/5,SMMC-7721 and Q3 as well as hepatoma cells SMMC-7721 transfected with pCMV or pCMV-TTR were analyzed for TTR expression by Northern hybridization.The low level of TTR expression was found in both hepatoma cell lines and in SMMC-7721 cells transfected with pCMV alone.However,a remarkable TTR mRNA expression was observed in hepatoma SMMV-7721 cells transfected with pCMV-TTR.It seems possible that TTR gene might be a candidate of cancer suppressor gene for human hepatic cancer. 相似文献
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用RT-PCR方法快速克隆了Wistar大鼠脑神经元特异性烯醇化酶(NSE)的cDNA,将此包括编码全长NSE433个氨基醚的DNA片段重组入pUC质粒,并用PCR方法测定了全部顺序,经重复实验,发现Wistar大鼠与Forss-Petter报导的SD大鼠NSE基因顺序,有两外单碱基的差别,其中一个涉及氨基酸的改变。同时还对RNA的提取及长片段DNA的RT-PCR扩增进行了方法学的探讨。 相似文献
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C. Horstmann B. Schlesier A. Otto S. Kostka K. Müntz 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(7):867-874
Legumin, which amounts to approximately 55% of the seed protein in field beans (Vicia faba L. var. minor), is a representative of the 12S storage globulin family. The 12S storage globulins are hexameric holoprotein molecules composed of different types of polymorphic subunits encoded by a multigene family. Type-A legumin subunits contain methionine whereas type-B are methionine-free subunits. Sequencing of two different type A-specific cDNAs, as well as an FPLC/HPLC-based improvement of subunit fractionation and peptide mapping with subsequent partial amino-acid sequencing, permit the assignment of some of the polymorphic legumin subunits to members of the multigene family. Two different type A subunits (A1 and A2) correspond to the two different cDNA clones pVfLa129 (A2) and 165 (A1), but microheterogeneity in the amino-acid sequences indicates that polymorphic variants of both representatives of this type may exist. Two groups of published type B-specific gene sequences (LeB7, and LeB2, LeB4, LeB6, respectively) are represented by two polymorphic subunit fractions (B3I, B3II, and B4I, B4II). A seventh clone, LeB3, encodes one of the large legumin subunits that is only a minor component of the legumin seed protein complex. 相似文献