UAS sequences regulate expression of a SPLICS (split-GFP-based contact site sensor) reporter that can be used to quantify contact between peroxisomes and mitochondria within a 8-10 nm range. The UAS sequences drive expression of two open reading frames separated by a P2A peptide (to ensure separate translation of the two ORFs and equimolar amounts of the two expressed proteins). The first ORF encodes a protein composed of a peroxisome membrane targeting sequence, a 'short' spacer of 29 amino acids, and the spGFP11 split fragment. The second ORF encodes the spGFP1-10 split fragment tagged with sequence that anchors it to the mitochondrial outer membrane. Where the peroxisomes and mitochondrial outer membranes are in close proximity, the spGFP1-10 and spGFP11 moieties can self-assemble to reconstitute a functional sfGFP protein, resulting in fluorescent puncta (details from PMID:33247103).