Fischer S G, Laemmli U K
Biochemistry. 1980 May 13;19(10):2240-6. doi: 10.1021/bi00551a038.
We have examined the relationship of phosphate content in histone H1 of Physarum polycephalum to mitotic chromosome condensation and affinity for deoxyribonucleic acid (DNA). H1 undergoes a series of posttranslational phosphorylations which increase its apparent molecular weight on NaDodSO4-polyacrylamide gels. Our studies confirm the observation by Bradbury and co-workers [Bradbury, E. M., Inglis, R. J., Matthews, H. R., & Sarner, N (1973) Eur. J. Biochem. 33, 131-139; Bradbury, E. M., Inglis, R. J., & Matthews, H. R. (1974) Nature (London) 247, 257-261] that the accumulation of phosphate in H1 increases markedly shortly before the onset of mitosis. However, we show in pulse-chase experiments with both 32PO4H1 and [14C]lysine H1 that there is no significant dephosphorylation of the histone either during or shortly after mitosis, suggesting that nonspecific postmitotic dephosphorylation of H1 is not a prerequisite for chromosome decondensation. We also show that both phosphorylated and unphosphorylated forms of H1 bind with somewhat greater affinity to single-stranded DNA-cellulose than to native DNA-cellulose and that phosphorylation weakens the affinity of H1 to both forms of DNA-cellulose.
我们研究了多头绒泡菌组蛋白H1中的磷酸盐含量与有丝分裂染色体凝聚以及对脱氧核糖核酸（DNA）亲和力之间的关系。H1会经历一系列翻译后磷酸化过程，这会增加其在十二烷基硫酸钠 - 聚丙烯酰胺凝胶上的表观分子量。我们的研究证实了布拉德伯里及其同事的观察结果[布拉德伯里，E.M.，英格利斯，R.J.，马修斯，H.R.，& 萨纳，N（1973）欧洲生物化学杂志33，131 - 139；布拉德伯里，E.M.，英格利斯，R.J.，& 马修斯，H.R.（1974）自然（伦敦）247，257 - 261]，即在有丝分裂开始前不久，H1中磷酸盐的积累会显著增加。然而，我们在使用³²P标记的磷酸组蛋白H1和[¹⁴C]赖氨酸组蛋白H1进行的脉冲追踪实验中表明，在有丝分裂期间或之后不久，组蛋白都没有明显的去磷酸化现象，这表明H1在有丝分裂后的非特异性去磷酸化不是染色体解聚的先决条件。我们还表明，H1的磷酸化形式和未磷酸化形式与单链DNA - 纤维素的结合亲和力都略高于与天然DNA - 纤维素的结合亲和力，并且磷酸化会削弱H1与两种形式的DNA - 纤维素的亲和力。
