在体外被小牛胸腺蛋白激酶NII磷酸化的酸性五肽在Mg2+阳离子存在的情况下与DNA结合。

Acidic pentapeptide phosphorylated in vitro by calf thymus protein kinase NII binds to DNA in the presence of Mg2+ cations.

作者信息

Chillemi F, Lugaro G, Boari D, Cardellini E, Bramucci M, Miano A, Amici D, Gianfranceschi G L, Durban E

机构信息

Department of Organic and Industrial Chemistry, University of Milan, Italy.

出版信息

FEBS Lett. 1991 Oct 7;291(1):67-70. doi: 10.1016/0014-5793(91)81105-h.

DOI:10.1016/0014-5793(91)81105-h

PMID:1936253

Abstract

The pentapeptide pyroGlu-Ala-Glu-Ser-Asn has been synthetized and phosphorylated in vitro at level of serine by protein kinase NII isolated from calf thymus chromatin. It is noteworthy that the calf thymus kinase NII shows a remarkable affinity for this peptide. The [32P]peptide is able to bind to several DNAs in the presence of Mg2+ (lambda phage, calf thymus, pBR540 plasmid). This binding appears not specific with regard to the type of DNA and its base sequence. These data support the hypothesis that phosphorylated acidic domains of nuclear nonhistone proteins could bind directly to DNA in the presence of Mg2+ cations.

摘要

已合成了五肽焦谷氨酸-丙氨酸-谷氨酸-丝氨酸-天冬酰胺，并通过从小牛胸腺染色质中分离出的蛋白激酶NII在丝氨酸水平进行了体外磷酸化。值得注意的是，小牛胸腺激酶NII对该肽表现出显著的亲和力。在存在Mg2+（λ噬菌体、小牛胸腺、pBR540质粒）的情况下，[32P]肽能够与多种DNA结合。这种结合似乎对DNA的类型及其碱基序列不具有特异性。这些数据支持这样一种假说，即在Mg2+阳离子存在的情况下，核非组蛋白的磷酸化酸性结构域可直接与DNA结合。