Laboratory for Structural Biochemistry, Stem Cell and Developmental Biology, Genome Institute of Singapore, Genome, 60 Biopolis Street, Singapore.
Nucleic Acids Res. 2012 Sep 1;40(17):8721-32. doi: 10.1093/nar/gks611. Epub 2012 Jun 26.
Zfp206 (also named as Zscan10) belongs to the subfamily of C(2)H(2) zinc finger transcription factors, which is characterized by the N-terminal SCAN domain. The SCAN domain mediates self-association and association between the members of SCAN family transcription factors, but the structural basis and selectivity determinants for complex formation is unknown. Zfp206 is important for maintaining the pluripotency of embryonic stem cells presumably by combinatorial assembly of itself or other SCAN family members on enhancer regions. To gain insights into the folding topology and selectivity determinants for SCAN dimerization, we solved the 1.85 Å crystal structure of the SCAN domain of Zfp206. In vitro binding studies using a panel of 20 SCAN proteins indicate that the SCAN domain Zfp206 can selectively associate with other members of SCAN family transcription factors. Deletion mutations showed that the N-terminal helix 1 is critical for heterodimerization. Double mutations and multiple mutations based on the Zfp206SCAN-Zfp110SCAN model suggested that domain swapped topology is a possible preference for Zfp206SCAN-Zfp110SCAN heterodimer. Together, we demonstrate that the Zfp206SCAN constitutes a protein module that enables C(2)H(2) transcription factor dimerization in a highly selective manner using a domain-swapped interface architecture and identify novel partners for Zfp206 during embryonal development.
Zfp206（也称为 Zscan10）属于 C(2)H(2)锌指转录因子亚家族，其特征在于 N 端的 SCAN 结构域。SCAN 结构域介导 SCAN 家族转录因子成员之间的自我缔合和缔合，但对于复合物形成的结构基础和选择性决定因素尚不清楚。Zfp206 对于维持胚胎干细胞的多能性很重要，推测是通过自身或其他 SCAN 家族成员在增强子区域上的组合组装来实现的。为了深入了解 SCAN 二聚体化的折叠拓扑和选择性决定因素，我们解析了 Zfp206 的 SCAN 结构域的 1.85 Å 晶体结构。使用 20 种 SCAN 蛋白的面板进行的体外结合研究表明，SCAN 结构域 Zfp206 可以选择性地与其他 SCAN 家族转录因子成员结合。缺失突变表明，N 端螺旋 1 对于异二聚化至关重要。基于 Zfp206SCAN-Zfp110SCAN 模型的双突变和多突变表明，结构域交换拓扑结构可能是 Zfp206SCAN-Zfp110SCAN 异二聚体的首选。总之，我们证明了 Zfp206SCAN 构成了一个蛋白质模块，它使用结构域交换界面结构以高度选择性的方式实现 C(2)H(2)转录因子二聚化，并确定了胚胎发育过程中 Zfp206 的新伴侣。
