Cytosolic LATS1 and LATS2 are phosphorylated by phospho-STK4(MST1)/N (Graves et al. 1998; Lee et al. 2001). LATS proteins are known to form complexes with MOB1 proteins and this reaction is annotated with LATS:MOB1 complexes as its substrate. Serine-909 and threonine-1097 have been identified as LATS1 residues phosphorylated by STK4 (MST1) kinase. The target residues of LATS2 have not been identified experiemntally but are inferred to be serine-871 and threonine-1041 based on sequence similarity.