Structural Insights into the Tumor-Promoting Function of the MTDH-SND1 Complex.
Guo, F., Wan, L., Zheng, A., Stanevich, V., Wei, Y., Satyshur, K.A., Shen, M., Lee, W., Kang, Y., Xing, Y.(2014) Cell Rep 8: 1704-1713
- PubMed: 25242325 
- DOI: https://doi.org/10.1016/j.celrep.2014.08.033
- Primary Citation of Related Structures:  
4QMG - PubMed Abstract: 
Metadherin (MTDH) and Staphylococcal nuclease domain containing 1 (SND1) are overexpressed and interact in diverse cancer types. The structural mechanism of their interaction remains unclear. Here, we determined the high-resolution crystal structure of MTDH-SND1 complex, which reveals an 11-residue MTDH peptide motif occupying an extended protein groove between two SN domains (SN1/2), with two MTDH tryptophan residues nestled into two well-defined pockets in SND1. At the opposite side of the MTDH-SND1 binding interface, SND1 possesses long protruding arms and deep surface valleys that are prone to binding with other partners. Despite the simple binding mode, interactions at both tryptophan-binding pockets are important for MTDH and SND1's roles in breast cancer and for SND1 stability under stress. Our study reveals a unique mode of interaction with SN domains that dictates cancer-promoting activity and provides a structural basis for mechanistic understanding of MTDH-SND1-mediated signaling and for exploring therapeutic targeting of this complex.
Organizational Affiliation: 
McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, School of Medicine and Public Health, Madison, WI 53706, USA.