Phosphatidylserine translocation to the mitochondrion is an ATP-dependent process in permeabilized animal cells

Journal Article · Fri Dec 01 00:00:00 EST 1989 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.86.24.9921· OSTI ID:7138056

Voelker, D R ^[1]

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1. National Jewish Center for Immunology and Respiratory Medicine, Denver, CO (USA)

Chinese hamster ovary (CHO-K1) cells were pulse labeled with ({sup 3}H)serine, and the synthesis of phosphatidyl({sup 3}H)ethanolamine from phosphatidyl({sup 3}H)serine during the subsequent chase was used as a measure of lipid translocation to the mitochondria. When the CHO-K1 cells were pulse labeled and subsequently permeabilized with 50 {mu}g of saponin per ml, there was no significant turnover of nascent phosphatidyl({sup 3}H)serine to form phosphatidyl({sup 3}H)ethanolamine during an ensuring chase. Supplementation of the permeabilized cells with 2 mM ATP resulted in significant phosphatidyl({sup 3}H)ethanolamine synthesis (83% of that found in intact cells) from phosphatidyl({sup 3}H)serine during a subsequent 2-hr chase. Phosphatidyl({sup 3}H)ethanolamine synthesis essentially ceased after 2 hr in the permeabilized cells. The translocation-dependent synthesis of phosphatidyl({sup 3}H)ethanolamine was a saturable process with respect to ATP concentration in permeabilized cells. The conversion of phosphatidyl({sup 3}H)serine to phosphatidyl({sup 3}H)ethanolamine did not occur in saponin-treated cultures supplemented with 2 mM AMP, 2 mM 5{prime}-adenylyl imidodiphosphate, or apyrase plus 2 mM ATP. ATP was the most effective nucleotide, but the addition of GTP, CTP, UTP, and ADP also supported the translocation-dependent synthesis of phosphatidyl({sup 3}H)ethanolamine albeit to a lesser extent. These data provide evidence that the interorganelle translocation of phosphatidylserine requires ATP and is largely independent of soluble cytosolic proteins.

• OSTI ID: 7138056
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Vol. 86:24; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
LIPIDS
TRANSLOCATION
PHOSPHOLIPIDS
BIOSYNTHESIS
TRITIUM COMPOUNDS
ATP
CHO CELLS
DOSE-RESPONSE RELATIONSHIPS
MITOCHONDRIA
PERMEABILITY
SERINE
AMINO ACIDS
ANIMAL CELLS
CARBOXYLIC ACIDS
CELL CONSTITUENTS
ESTERS
HYDROGEN COMPOUNDS
HYDROXY ACIDS
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANOIDS
SYNTHESIS
550201* - Biochemistry- Tracer Techniques