Human dynamin-1-like protein (DNM1L, also known as Drp1) belongs to the dynamin superfamily. It is a large GTPase involved in segregating mitochondria and peroxisomes []. During mitochondrial fission, Drp1 is recruited from the cytosol onto the mitochondrial outer membrane, where it assembles into puncta. These puncta consist of oligomeric Drp1 complexes that wrap around and constrict the mitochondrial tubule to mediate fission []. Drp1 is required for normal brain development, including that of cerebellum []. It maintains the integrity of mitochondrial structure and function in mouse heart and brain [].Dynamin superfamily members are large GTPases [], including dynamins, dynamin-like proteins, OPA1, Mx proteins, mitofusins and guanylate-binding proteins/atlastins [, , , ]. They are involved in the scission of a wide range of vesicles and organelles and play a role in many processes including budding of transport vesicles, division of organelles, cytokinesis and pathogen resistance. The minimal distinguishing architectural features that are common to all dynamins, and are distinct from other GTPases, are the structure of the large GTPase domain (300 amino acids) and the presence of two additional domains, the middle domain and the GTPase effector domain (GED), which are involved in oligomerisation and regulation of the GTPase activity.
This entry represents the mitochondrial dynamics protein MID49/MID51. Most members of this protein family contain a Mab-21 domain and are found in chordates.In humans, MID49 and MID51 are outer membrane proteins involved in the regulation of mitochondrial organisation and required for mitochondrial fission by promoting the recruitment and association of the fission mediator dynamin-related protein 1 (DNM1L) to the mitochondrial surface independently of the mitochondrial fission FIS1 and MFF proteins. They also regulate DNM1L GTPase activity [, , , , ]. Deregulation of these proteins has been linked to human diseases such as pulmonary arterial hypertension [].
