Strongly expressed in vertebrae, brain, intestine and stomach. First detected at 8 dpc in the ossification center and the spinal cord. From this stage up to birth, expression extends throughout the bone tissue and strong expression is detected in the vertebrae. At 16 dpc, detected in the developing brain, including the prosencephalon, mesencephalon, diencephalon, telencephalon and rhombencephalon, and in the intestine. Faint expression at 16 dpc in the lung. Belongs to the complex I NDUFA4 subunit family.