InterPro domain: IPR029930

Uracil salvage is importance for plant development [ 1 , 2 ]. The genome of Arabidopsis thaliana encodes several proteins, known as uridine kinase-like (UKL1-5), with dual domains for uridine kinase and uracil phosphoribosyltransferase [ 3 ]. Uridine kinase (UK) and uracil phosphoribosyltransferase (UPRT) are enzymes catalysing the formation of uridine 5'-monophosphate (UMP) from uridine and ATP, and from uracil and phosphoribosyl-alpha-1-pyrophosphate (PRPP), respectively, in the pyrimidine salvage pathway. The dual-domain UKL proteins seem to lack the UPRT activity [ 4 ].

1. Plastid uridine salvage activity is required for photoassimilate allocation and partitioning in Arabidopsis. Plant Cell 23, 2991-3006
2. Uracil salvage is necessary for early Arabidopsis development. Plant J. 60, 280-91
3. Functional characterization of a gene encoding a dual domain for uridine kinase and uracil phosphoribosyltransferase in Arabidopsis thaliana. Plant Mol. Biol. 63, 465-77