RING finger ubiquitin-protein isopeptide ligase Nrdp1/FLRF regulates parkin stability and activity
Department of Medicine; Program in Neuroscience
Animals; Drosophila; Drosophila Proteins; Humans; Kinetics; Polymerase Chain Reaction; Proteins; Ubiquitin-Protein Ligases
Life Sciences | Medicine and Health Sciences
Parkin is a ubiquitin-protein isopeptide ligase. It has been suggested that loss of function in parkin causes accumulation and aggregation of its substrates, leading to death of dopaminergic neurons in Parkinson disease. Using the yeast two-hybrid screen, we isolated a RING finger protein that interacted with the N terminus of parkin in a Drosophila cDNA library. Interaction between human parkin and the mammalian RING finger protein homologue Nrdp1/FLRF, a ubiquitin-protein isopeptide ligase that ubiquitinates ErbB3 and ErbB4, was validated by in vitro binding assay, co-immunoprecipitation, and immunofluorescence co-localization. Significantly, pulse-chase experiments showed that cotransfection of Nrdp1 and parkin reduced the half-life of parkin from 5 to 2.5 h. Consistent with these findings, we further observed that degradation of CDCrel-1, a parkin substrate, was facilitated by overexpression of parkin protein. However, co-transfection of Nrdp1 with parkin reversed the effects of parkin on CDCrel-1 degradation. We conclude that Nrdp1 is a parkin modifier that accelerates degradation of parkin, resulting in a reduction of parkin activity.
DOI of Published Version
J Biol Chem. 2005 Mar 11;280(10):9425-30. Epub 2005 Jan 4. Link to article on publisher's site
The Journal of biological chemistry
Zhong, Ling; Tan, Ying; Zhou, An; Yu, Qingming; and Zhou, Jianhua, "RING finger ubiquitin-protein isopeptide ligase Nrdp1/FLRF regulates parkin stability and activity" (2005). Open Access Articles. 699.