Accession Number : ADA180015

Title :   Modulation of Phospholipase A2 Activity by Actin and Myosin.

Descriptive Note : Final rept. 1 Apr 86-1 Apr 87,

Corporate Author : ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA

Personal Author(s) : DuBose,D A ; Sherpro,D ; Hechtman,H B

PDF Url : ADA180015

Report Date : 15 Apr 1987

Pagination or Media Count : 38

Abstract : Endothelial cell prostacyclin (Phosphogluculsomerase) production is closely coupled with cell shape. Since shape change implies cytoskeletal modulations, this finding may be an important clue to implicate cytoskeletal constituents in a mechanism regulating eicosanoid metabolism. Endothelial cells with a diffuse F-actin distribution generate more PGI than cells with many discrete F-actin stress fibers. Because actin can modulate enzyme activity, the myofibril protein effects on phopholipase A(PLA), the rate limiting eicosanoid cascade enzyme, were studied. F-actin stimulated whereas G-actin suppressed enzyme activity. Myosin in the presence of F-actin, the F-action stimulatory effect was significantly reduced. These findings suggest that the correlation of endothelial cell PGI metabolic modulation to cell shape and actin distribution was perhaps due to changes in PLA activity as a direct result of alterations in the polymerized state of actin and the degree of actin-myosin stress fiber formation.

Descriptors :   *METABOLISM, *MYOSIN, *CARBOXYLIC ESTER HYDROLASES, *MUSCLE PROTEINS, SHAPE, CELLS, ENDOTHELIUM, MODULATION, PRODUCTION, CORRELATION, CELLS(BIOLOGY), PROTEINS, METABOLITES, HEMOLYSIS, ENZYME CHEMISTRY, ERYTHROCYTES, PHOSPHOLIPIDS

Subject Categories : Anatomy and Physiology
      Biochemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE