The protein contains three coiled coil domains, which may play a role in its interactions with the cytoskeleton. These domains are the only regions in the HEI-C protein with homology to other proteins of known function. When the gene is overexpressed in yeast, it induces pseudohyphal growth and agar invasion.
Protein expression is localized primarily to the cytoplasm in single cells.
In addition, in cells undergoing mitosis, HEI-C is localized to the mitotic spindle. HEI-C interacts with Ost and dynamitin. Ost is a protooncogene. Regulation of cell-cell adhesion is essential for control of fundamental biological processes including embryogenesis, formation and maintenance of tissue structure, cellular migration through tissues, and metastatic invasion and establishment of malignant cells. Mitotic spindle function and dynamics is a site of cell cycle regulation and potentially affects cell growth.