Lockard R E
FEBS Lett. 1987 Jul 27;219(2):410-4. doi: 10.1016/0014-5793(87)80262-4.
Proteins in direct contact with translationally active and repressed duck globin mRNA were determined by irradiating blood or lysates with ultraviolet light. Cross-linked proteins from polyribosomes and free mRNP particles were 14C-labeled by reductive methylation and identified on SDS-polyacrylamide gels upon autoradiography. Results indicate that ten cross-linked proteins are common to both polysomal and free mRNP, however, a 44 kDa protein appears to be specific for repressed mRNP particles. Furthermore, the notable lack of cross-linked proteins in the 20-30 kDa range in free mRNP supports the view that the characteristic low molecular mass 'prosomal' proteins, previously found associated with translationally repressed duck globin free mRNP [(1984) EMBO J. 3, 29-34], do not interact directly with the mRNA molecule.
通过用紫外线照射血液或裂解物，确定与具有翻译活性和受抑制的鸭珠蛋白mRNA直接接触的蛋白质。来自多核糖体和游离mRNP颗粒的交联蛋白通过还原甲基化进行14C标记，并在放射自显影后在SDS-聚丙烯酰胺凝胶上进行鉴定。结果表明，十种交联蛋白在多核糖体和游离mRNP中都很常见，然而，一种44 kDa的蛋白似乎是受抑制的mRNP颗粒所特有的。此外，游离mRNP中明显缺乏20-30 kDa范围内的交联蛋白，这支持了以下观点：先前发现与翻译受抑制的鸭珠蛋白游离mRNP相关的特征性低分子量“前体小体”蛋白[(1984) EMBO J. 3, 29-34]并不直接与mRNA分子相互作用。
