Saudek V, Pasley H S, Gibson T, Gausepohl H, Frank R, Pastore A
Merrell Dow Research Institute, Strasbourg, France.
Biochemistry. 1991 Feb 5;30(5):1310-7. doi: 10.1021/bi00219a022.
The structure of the basic region (i.e., the region responsible for sequence-specific binding to DNA) of the transcriptional activator GCN4 was studied. Two peptide fragments containing either the basic region alone (residues 240-280) or the basic and the dimerization leucine zipper domains (220-280) were synthesized and investigated by nuclear magnetic resonance and circular dichroic spectroscopy. The basic region in the absence of DNA appears as a mobile flexible segment folded into a loose helix. The helical stability increases upon addition of trifluoroethanol and/or lowering of the temperature. Dimerization via the leucine zipper does not affect the three-dimensional structure of the basic region. Possible consequences for the binding to DNA are discussed.
对转录激活因子GCN4的碱性区域(即负责与DNA进行序列特异性结合的区域)的结构进行了研究。合成了两个肽片段,一个仅包含碱性区域(残基240 - 280),另一个包含碱性区域和二聚化亮氨酸拉链结构域(220 - 280),并通过核磁共振和圆二色光谱进行了研究。在没有DNA的情况下,碱性区域表现为一个折叠成松散螺旋的可移动柔性片段。加入三氟乙醇和/或降低温度后,螺旋稳定性增加。通过亮氨酸拉链进行二聚化并不影响碱性区域的三维结构。文中讨论了其与DNA结合可能产生的后果。