Crystallization and preliminary X-ray diffraction analysis of human importin β-Snail zinc finger domain complex

Snail is a C2H2‐type zinc finger transcriptional repressor that induces epithelial–mesenchymal transition by repression of E‐cadherin expression levels during embryonic development and tumour progression. Snail is imported into the nucleus by importin β through direct binding with its four zinc finger domain. The complex between importin β and Snail four zinc finger domain was crystallized in order to understand the nuclear transport mechanism of Snail. The constituents of the complex were separately expressed and were then co‐purified and crystallized by the hanging‐drop vapour‐diffusion method. The crystals belonged to space group C2, with unit‐cell parameters a = 228.2, b = 77.5, c = 72.0 Å, β = 100.9° and diffracted to 2.5 Å resolution.