DLP-1 is believed to concentrate long oligomers, which use Guanosine Triphosphate hydrolysis to constrict mitochondrial tubules during fission. Mitochondrial Fission 1 is an outer-membrane protein that works with DLP-1 during the fission process. Mitofusin-1 and Mitofusin-2 are part of the GTPase family, found in the outer membrane space, and mediate the fusion process. These proteins are also responsible for mitochondrial lashing. Mutations in Presenilin-1 and Presenilin-2 proteins lead to AD expression. These two proteins encode amyloid precursor protein, and in the presence of Presenilin-1,2 mutations, individuals have a high probability of developing AD.