Sphingolipid Metabolic Pathway: An Overview of Major Roles Played in Human Diseases

Figure 2

Key reactions involved in the sphingolipid metabolic pathway. Ceramide is produced in the ER and later transported to the Golgi complex for further conversion to complex sphingolipids. In addition to de novo synthesis, ceramide is also generated by hydrolysis of sphingomyelin. Ceramide is subject to conversion to various other sphingolipid intermediates like ceramide-1-phosphate, sphingosine, and sphingosine-1-phosphate. Cellular compartments are represented by boxes and enzymes are italicized. CDASE: ceramidase; CERK: ceramide kinase; CERS: ceramide synthase; CERT: ceramide transfer protein; DEGS: dihydroceramide desaturase; ER: endoplasmic reticulum; GBA: glucosyl ceramidase; GC: Golgi complex; KDSR: 3-keto dihydrosphinganine reductase; PM: plasma membrane; PPAP2A/B/C: phosphatidic acid phosphatase 2A/B/C; SGMS: sphingomyelin synthase; SGPP: sphingosine-1-phosphate phosphatase; SMPD: sphingomyelin phosphodiesterase; SPHK: sphingosine kinase; SPT: serine palmitoyll transferase; UGCG: UDP-glucose ceramide glucosyltransferase.