Yun J, Puri R, Yang H, Lizzio MA, Wu C, Sheng ZH, Guo M. MUL1 acts in parallel to the PINK1/parkin pathway in regulating mitofusin and compensates for loss of PINK1/parkin. Elife. 2014 Jun 4;3:e01958. PMID: 24898855.
From the abstract: "In this study, we show that MUL1 suppresses PINK1 or parkin mutant phenotypes in Drosophila. ... We further show that removing MUL1 in PINK1 or parkin loss-of-function mutant aggravates phenotypes caused by loss of either gene alone ... Together, these observations show that MUL1 acts in parallel to the PINK1/parkin pathway on a shared target mitofusin to maintain mitochondrial integrity. The MUL1 pathway compensates for loss of PINK1/parkin in both Drosophila and mammals and is a promising therapeutic target for PD."
Shiba-Fukushima K, Inoshita T, Hattori N, Imai Y. PINK1-Mediated Phosphorylation of Parkin Boosts Parkin Activity in Drosophila. PLoS Genet. 2014 Jun 5;10(6):e1004391. PMID: 24901221.
From the abstract: "Two genes linked to early onset Parkinson's disease, PINK1 and Parkin, encode a protein kinase and a ubiquitin-ligase, respectively. Both enzymes have been suggested to support mitochondrial quality control. ... Our data reveal that Parkin phosphorylation regulates not only mitochondrial function but also the neuronal activity of dopaminergic neurons in vivo, suggesting that the appropriate regulation of Parkin phosphorylation is important for muscular and dopaminergic functions."