This gene encodes a homeobox protein belonging to the TALE ('three amino acid loop extension') family of homeodomain-containing proteins. TALE homeobox proteins are highly conserved transcriptional regulators and several members have been shown to be essential contributors to developmental programs. In mice, a knock-out of this gene leads to lethality at embryonic day 14, accompanied with hemorrhaging. Embryos lacking this gene show defects in tissues derived from the neural crest, suggesting a critical role of this gene during cranial and cardiac neural crest cell development. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2016]