May function as a transcriptional regulator. Homodimer or heterodimer (Potential). Interacts with HOXC8 (By similarity). Ubiquitous. Strongly expressed in testis. First expressed at 7 dpc. At 8.5-9 dpc expressed in all developing organs. Later on during embryogenesis shows a more restricted expression pattern. At 9.5-12.5 dpc it is strongly expressed in the developing brain, optic vesicle and the otic placode. May result from the retention of an intron. It is uncertain whether Met-1 or Met-25 is the initiator. Truncated N-terminus. Extended N-terminus.