Functional classification of SPHK2-interacting proteins identified by mass spectrometry. Numbered sectors denote: ① AMPK signaling complex and upstream regulators; ② Glycolytic enzymes and carbon metabolism; ③ DNA damage response and repair machinery; ④Histone deacetylase family and epigenetic modifiers; ⑤ Lipid biosynthesis and fatty acid metabolism; ⑥ MAPK/RTK signaling cascade.