central domain found in ankyrin repeat and SAM domain-containing protein 4B
Ankyrin repeat and SAM domain-containing protein 4B (ANKS4B), also called Harmonin-interacting ankyrin repeat-containing protein (Harp), is highly expressed in intestine and is essential for intermicrovillar adhesion. As part of the intermicrovillar adhesion complex (IMAC), ANKS4B plays a role in epithelial brush border differentiation, controlling microvilli organization and length. It may be involved in cellular response to endoplasmic reticulum stress. ANKS4B consists of four N-terminal ANK repeats, a central region, and a sterile alpha motif (SAM) followed by a C-terminal type I PDZ binding motif (PBM). This model corresponds to the central region (CEN) of ANKS4B, which contains the conserved regions CEN1 and CEN2. CEN is directly responsible for binding to the N-terminal MyTH4-FERM-SH3 supramodule of MYO7B, with a mechanism highly analogous to the interaction between USH1G and MYO7A.