Shen B, Arese M, Gualandris A, Rifkin D B
Department of Cell Biology, Kaplan Cancer Center, and the Raymond and Beverly Sackler Foundation Laboratory, New York University Medical Center, New York, New York, 10016, USA.
Biochem Biophys Res Commun. 1998 Nov 18;252(2):524-8. doi: 10.1006/bbrc.1998.9677.
By using the yeast two-hybrid system, we identified the ribosomal protein L6/TAXREB107 as an intracellular partner for FGF-2. L6/TAXREB107 also mediates the DNA binding of the HTLV-1 transactivator Tax. In vitro binding experiments indicated that both the high-molecular-weight forms (HMW) and the 18-kDa form of FGF-2 bind to L6/TAXREB107. Deletion analysis suggested that L6/TAXREB107 has two binding sites for HMW FGF-2 and one binding site for 18-kDa FGF-2, implying that the unique N-terminal extension of the HMW FGF-2 is one of the binding domains for L6/TAXREB107. Transfection assays showed that high expression of either HMW or 18 kDa FGF-2 stimulates Tax-mediated transactivation in NIH 3T3 cells. This result suggests a possible role of FGF-2 in Tax-mediated HTLV-1 transformation as well as FGF-2 binding to ribosomes and/or their precursors.
通过使用酵母双杂交系统，我们鉴定出核糖体蛋白L6/TAXREB107是FGF-2的细胞内结合伴侣。L6/TAXREB107还介导HTLV-1反式激活因子Tax与DNA的结合。体外结合实验表明，高分子量形式（HMW）的FGF-2和18 kDa形式的FGF-2均能与L6/TAXREB107结合。缺失分析表明，L6/TAXREB107具有两个与HMW FGF-2结合的位点和一个与18 kDa FGF-2结合的位点，这意味着HMW FGF-2独特的N端延伸是其与L6/TAXREB107结合的结构域之一。转染实验表明，HMW或18 kDa FGF-2的高表达均可刺激NIH 3T3细胞中Tax介导的反式激活。这一结果提示FGF-2在Tax介导的HTLV-1转化过程中可能发挥作用，同时也提示FGF-2与核糖体和/或其前体存在结合。
