RNF114 suppresses tumour metastasis through the regulation of PARP10

Background ADP-ribosylation is a multifunctional post-translational modification catalysed by intracellular ADP-ribosyltransferases. Previously, we demonstrated that the mono-ADP-ribosyltransferase PARP10 suppresses tumour metastasis through the negative regulation of Aurora A kinase activity. However, the mechanisms of PARP10 regulation and modification were unclear. Methods Interaction of RNF114 and PARP10 was identified by exogenous and endogenous reciprocal immunoprecipitation (IP) assays and pull-down assays. Ubiquitination of PARP10 by RNF114 was analysed by in vivo ubiquitination assays. Potential effects of ubiquitination on PARP10’s activity was detected by western blots and pull-down assays. Potential role of RNF114 in tumour metastasis were determined by migration and invasion assays and in vivo metastasis assay. Results That E3 ubiquitin ligase RNF114 is a partner of PARP10 was identified by IP assays. The auto-mono-ADP-ribosylation of PARP10 is required for the interaction of RNF114 and PARP10. RNF114 ubiquitinates PARP10 through K27-linked polyubiquitination, which enhances PARP10 enzymatic activity. Moreover, RNF114 deficiency promotes tumour cell migration and tumour metastasis through the regulation of PARP10 and its downstream signalling pathway. Conclusions Our findings identify RNF114 as a novel functional regulator of PARP10 and provide evidence of crosstalk between the components of K27-linked polyubiquitination and mono-ADP ribosylation.