ATPase Family, AAA Domain Containing Protein 3B (ATAD3B)

ATAD3B was overexpressed in 3 of 4 head and neck carcinomas compared with healthy oral mucosa. In situ hybridization confirmed ATAD3B overexpression in 5 head and neck carcinomas compared with normal tissue. Expression of both ATAD3B isoforms was induced by MYC. A recombinant N-terminal fragment of ATAD3B containing residues 44 through 247 displayed sequence-independent binding of tightly supercoiled mtDNA that included a short, triple-stranded noncoding region called a displacement loop, or D loop. This ATAD3B fragment also bound duplex DNA and single-stranded DNA, but with lower affinity. The N-terminal ATAD3B fragment and RecA (RAD51) bound to a synthetic D loop, and the pronounced mobility shift effected by the ATAD3B fragment suggested that it accrues multiple mtDNA molecules or that each D loop is bound by a large number of ATAD3B molecules