Cavalieri L F, Sonenberg M, Cronin-Sheridan A P, Priddle M
Acta Haematol. 1975;54(4):248-56. doi: 10.1159/000208082.
Smooth membranes have been isolated from a human diploid line of lymphocytes. These membranes exhibit an endogenous DNA-synthesizing capability which is partially destroyed by prior treatment with RNase. In order to ascertain the role of the membranes in the DNA synthesis we have examined the conformation of the membrane proteins by observing fluorescence changes of the intrinsic probe, tryptophan. We have observed that on addition of the deoxynucleoside-5'-triphosphates, which permits DNA synthesis, there are fluorescence changes due to the tryptophan residue; when DNA synthesis is prevented by omitting some of the precursor triphosphates, fluorescence changes are absent. These effects have been observed with plasma and nuclear membrane fractions; the former may contain a small fraction of the latter. Similar membrane preparations from non-lymphoid cells do not process the endogenous DNA-synthesizing system, as shown by the lack of incorporation of radioactive precursors of fluorescence changes.
已从人二倍体淋巴细胞系中分离出光滑膜。这些膜具有内源性DNA合成能力，用核糖核酸酶预先处理会部分破坏这种能力。为了确定膜在DNA合成中的作用，我们通过观察内在探针色氨酸的荧光变化来研究膜蛋白的构象。我们观察到，加入允许DNA合成的脱氧核苷-5'-三磷酸时，色氨酸残基会引起荧光变化；当通过省略一些前体三磷酸来阻止DNA合成时，则没有荧光变化。在质膜和核膜组分中都观察到了这些效应；前者可能含有一小部分后者。非淋巴细胞的类似膜制剂不具备内源性DNA合成系统，这可通过缺乏放射性前体的掺入或荧光变化来证明。
