May contribute to UTP accumulation needed for blast transformation and proliferation. ATP + uridine = ADP + H(+) + UMP ATP + cytidine = ADP + CMP + H(+) Pyrimidine metabolism; UMP biosynthesis via salvage pathway; UMP from uridine: step 1/1. Interacts with RNF19B. Ubiquitinated by RNF19B; which induces proteasomal degradation. Belongs to the uridine kinase family.