XPO1 (CRM1) binds to BACH1:Hemes

A small but significant fraction of XPO1 (CRM1) binds to BACH1. Several cysteine–proline (CP) dipeptide sequence in BACH1 are involved in heme binding, they also contain a nuclear export signal. The simplest model is that this region is involved in a heme-regulated interaction with XPO1 that mediates nuclear export. While XPO1 bound to BACH1 in GST pull-down assays, the nature of this interaction has yet to be extensively characterized (Suzuki et al, 2004).

XPO1（CRM1）与BACH1的结合比例虽小，却具有重要意义。在BACH1中，数个半胱氨酸-脯氨酸（CP）二肽序列参与血红素结合，并含有核输出信号。最简单的模型是，该区域参与血红素调控与XPO1的相互作用，从而介导核输出。尽管在GST pull-down实验中观察到XPO1与BACH1的结合，但此交互作用的本质尚待深入研究（Suzuki等，2004）。