IDENTIFICATION OF THE MITOCHONDRIAL NADH DEHYDROGENASE SUBUNIT-3 (ND3) AS A THYROID-HORMONE REGULATED GENE BY WHOLE GENOME PCR ANALYSIS

We previously described a modification of the whole genome PCR method which allowed us to characterize several genes whose expression is reg ulated by thyroid hormone in the mouse liver. Following this procedure , we now report the identification of the mitochondrial NADH dehydroge nase subunit 3 (ND3) gene as target of thyroid hormone. ND3 gene expre ssion is regulated by thyroid hormone in rat brain and heart. Sequenci ng and electrophoretic mobility shift assays confirmed the presence of a thyroid hormone receptor (TR)/c-erbA specific binding site in the m itochondrial ND3 gene. Hypothyroidism decreases ND3 mRNA levels in sev eral brain areas such as cortex and hippocampus during the early postn atal development. In line with the recent findings showing the presenc e of TR/c-erbA cc and a proteins inside the mitochondria, our results suggest the possibility of direct transcriptional regulation of mitoch ondrial genes by thyroid hormone. (C) 1995 Academic Press, Inc.