  Small Ubiquitin-related modifier (SUMO) proteins are widely expressed in
eukaryotic cells, which are reversibly coupled to their substrates by motif
recognition, called sumoylation. Two interesting questions are 1) how many
potential SUMO substrates may be included in mammalian proteomes, such as human
and mouse, 2) and given a SUMO substrate, can we recognize its sumoylation
sites? To answer these two questions, previous prediction systems of SUMO
substrates mainly adopted the pattern recognition methods, which could get high
sensitivity with relatively too many potential false positives. So we use
phylogenetic conservation between mouse and human to reduce the number of
potential false positives.
