Figure 1.

Regulation of the distribution of mitochondria DNA (mtDNA). (A) Mitochondrial dynamics regulate mtDNA. Mitochondrial fission and mtDNA segregation happened synchronously, and occur at the ER and mitochondrial contact site. Upon fission, the endoplasmic reticulum (ER) wraps the mitochondria, and then the cytosolic dynamic protein Drp1 is recruited to mediated mitochondria division. Blocking the fission leads to enlarged mitochondria and an mtDNA cluster. Mitochondrial fusion allows for two mitochondrial exchange substances, including mtDNA. The dysfunction of fusion leads to mtDNA deletion. (B) The mitochondrial inner membrane is involved in mtDNA distribution. Certain mitochondrial inner membrane proteins such as prohibitins and ATPase family AAA domain-containing protein 3 (ATAD3) are mtDNA-binding proteins. In addition, mtDNA nucleoid contacts with the mitochondrial cristae junction, and MICOS complex and Sam50, which are involved in the maintenance of the cristae structure, regulate mtDNA distribution.