Cocoa: a new mouse model for platelet storage pool deficiency.

We describe genetic, haematological and biochemical properties of a new mouse pigment mutant, cocoa (coa). Cocoa is a recessive mutation located on the centromeric end of chromosome 3 near the Car-2 locus. The mutation causes increased bleeding time accompanied by symptoms of platelet storage pool deficiency (SPD), including decreased platelet serotonin and decreased visibility of dense granules as analysed by electron microscopy of unfixed platelets. Dense granules were visible in normal numbers when platelets were incubated with the fluorescent dye, mepacrine. The intragranular environment, however, was abnormal as indicated by decreased flashing of mepacrine-loaded dense granules after exposure to ultraviolet light. Unlike the previously described seven mouse pigment mutations with SPD in which pigment granules, platelet dense granules and lysosomes are affected, the cocoa mutant had normal secretion of lysosomal enzymes from kidney proximal tubule cells and platelets. The cocoa mutation thus represents an example of a single gene which simultaneously affects melanosomes and platelet dense granules but probably does not affect lysosomes. The results indicate that melanosomes and platelet dense granules share steps in synthesis and/or processing. Cocoa may be a model for cases of human Hermansky-Pudlak syndrome in which functions of melanosomes and platelet dense granules, but not lysosomes, are involved.
AuthorsE K Novak, H O Sweet, M Prochazka, M Parentis, R Soble, M Reddington, A Cairo, R T Swank
JournalBritish journal of haematology (Br J Haematol) Vol. 69 Issue 3 Pg. 371-8 (Jul 1988) ISSN: 0007-1048 [Print] ENGLAND
PMID3408670 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)
  • Animals
  • Blood Platelet Disorders (blood)
  • Blood Platelets (ultrastructure)
  • Chromosomes, Human, Pair 3
  • Disease Models, Animal
  • Humans
  • Lysosomes (enzymology)
  • Mice
  • Mice, Inbred C57BL
  • Microscopy, Electron
  • Mutation
  • Platelet Storage Pool Deficiency (blood, enzymology, genetics)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: