title: Roles and regulation of phospholipid scramblases.
abstract: Phospholipid scramblase activity is involved in the collapse of phospholipid (PL) asymmetry at the plasma membrane leading to externalization of phosphatidylserine. This activity is crucial for initiation of the blood coagulation cascade and for recognition/elimination of apoptotic cells by macrophages. Efforts to identify gene products associated with this activity led to the characterization of PL scramblase (PLSCR) and XKR family members which contribute to phosphatidylserine exposure in response to apoptotic stimuli. Meanwhile, TMEM16 family members were identified to externalize phosphatidylserine in response to elevated calcium in Scott syndrome platelets, which is critical for activation of the coagulation cascade. Herein, we report their mechanisms of gene regulation, molecular functions independent of their scrambling activity, and their potential roles in pathogenic conditions.
authors.affiliation: Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States.
authors.forename: Karthik M
authors.initials: KM
authors.lastname: Kodigepalli
authors.affiliation: Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States.
authors.forename: Kiah
authors.initials: K
authors.lastname: Bowers
authors.affiliation: Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States.
authors.forename: Arielle
authors.initials: A
authors.lastname: Sharp
authors.affiliation: Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, United States. Electronic address: mnanjund@usf.edu.
authors.forename: Meera
authors.initials: M
authors.lastname: Nanjundan
mesh_terms: D000818:Animals; D017209:Apoptosis; D001778:Blood Coagulation Disorders / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D001792:Blood Platelets / Q000201:enzymology* / Q000473:pathology; D002462:Cell Membrane / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D006801:Humans; D010718:Phosphatidylserines / Q000235:genetics / Q000378:metabolism*; D049294:Phospholipid Transfer Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D010718:Phosphatidylserines; D049294:Phospholipid Transfer Proteins
keywords: Autoimmunity; Bacterial protection; Cancer; PL scramblase; Phospholipid scramblase; Scott syndrome; Transmembrane protein 16; Viral replication; XK-related protein