title: The role of mitochondrial fusion and StAR phosphorylation in the regulation of StAR activity and steroidogenesis.
abstract: The steroidogenic acute regulatory (StAR) protein regulates the rate-limiting step in steroidogenesis, i.e. the delivery of cholesterol from the outer (OMM) to the inner (IMM) mitochondrial membrane. StAR is a 37-kDa protein with an N-terminal mitochondrial targeting sequence that is cleaved off during mitochondrial import to yield 30-kDa intramitochondrial StAR. StAR acts exclusively on the OMM and its activity is proportional to how long it remains on the OMM. However, the precise fashion and the molecular mechanism in which StAR remains on the OMM have not been elucidated yet. In this work we will discuss the role of mitochondrial fusion and StAR phosphorylation by the extracellular signal-regulated kinases 1/2 (ERK1/2) as part of the mechanism that regulates StAR retention on the OMM and activity.
authors.affiliation: Biomedical Research Institute, INBIOMED, Department of Biochemistry, School of Medicine University of Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), C1121ABG, Argentina.
authors.forename: Ana F
authors.initials: AF
authors.lastname: Castillo
authors.affiliation: Biomedical Research Institute, INBIOMED, Department of Biochemistry, School of Medicine University of Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), C1121ABG, Argentina.
authors.forename: Ulises
authors.initials: U
authors.lastname: Orlando
authors.affiliation: Biomedical Research Institute, INBIOMED, Department of Biochemistry, School of Medicine University of Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), C1121ABG, Argentina.
authors.forename: Katia E
authors.initials: KE
authors.lastname: Helfenberger
authors.affiliation: Biomedical Research Institute, INBIOMED, Department of Biochemistry, School of Medicine University of Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), C1121ABG, Argentina.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Poderoso
authors.affiliation: Biomedical Research Institute, INBIOMED, Department of Biochemistry, School of Medicine University of Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), C1121ABG, Argentina. Electronic address: ernestopodesta@yahoo.com.ar.
authors.forename: Ernesto J
authors.initials: EJ
authors.lastname: Podesta
mesh_terms: D000818:Animals; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006801:Humans; D063154:Mitochondrial Dynamics; D051336:Mitochondrial Membranes / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D013256:Steroids / Q000096:biosynthesis*; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D010750:Phosphoproteins; D013256:Steroids; D000098682:Steroidogenic Acute Regulatory Protein; D048049:Extracellular Signal-Regulated MAP Kinases
keywords: ERK-dependent StAR phosphorylation; Mitochondrial dynamics; Mitochondrial phosphatases