| First Author | Gwynn B | Year | 1996 |
| Journal | Mol Biol Cell | Volume | 7 |
| Issue | Suppl | Pages | 550a (Abstr.) |
| Mgi Jnum | J:37510 | Mgi Id | MGI:84902 |
| Citation | Gwynn B, et al. (1996) Genetic mapping distinguishes the gene encoding protein 4.2 from the mouse platelet storage pool deficiency mutation pallid. Mol Biol Cell 7(Suppl):550a (Abstr.) |
| abstractText | Full text of Abstract: 550a Cytoskeleton-Membrane Interactions: Function II (3197-3202). 3197. GENETIC MAPPING DISTINGUISHES THE GENE ENCODING PROTEIN 4.2 FROM THE MOUSE PLATELET STORAGE POOL DEFICIENCY MUTATION PALLID. ((B. Gwynn. S. Ciciotte, C. Korsgren*, C.M. Cohen* and L.L. Peters)) The Jackson Laboratory, Bar Harbor, ME 04609, *St. Elizabeth's Medical Center, Boston, MA 02135. Several mouse mutations exist that are models of the Hermansky-Pudlak syndrome in humans, a platelet storage pool disease (SPD). In humans and mice, three subcellular organelles (melanosomes, lysosomes, and platelet dense bodies) are defective, resulting in dilution of coat color (albinism), abnormal lysosomal enzyme secretion, and increased bleeding time. Previously, the gene encoding the membrane skeleton-associated protein known as protein 4.2 (Epb4.2) was genetically localized on Chromosome 2 near the mouse SPD mutant pallid (pa). This and other data lead to the hypothesis that a defect in the Epb4.2 gene caused the pallid SPD phenotype. Here, we report additional analyses of protein 4.2 in pallid mice. No significant sequence variation is present in the pallid protein 4.2 cDNA or intron/exon boundaries compared to normal mice, and western blotting reveals normal immunoreactive protein 4.2 in pallid tissues. A genetic cross between C57BL/6J-pa/pa and Mus castaneous (Cast/Ei) was generated, and DNA from 88 phenotypically mutant F2 animals was analyzed to determine the origin of the protein 4.2 genes. Two animals carried both the Mus castaneous and pallid 4.2 alleles, indicating that genetic recombination had occurred between the pallid and protein 4.2 genes. One of these animals was bred to a pallid female. Offspring phenotypically indistinguishable from pallid and exhibiting increased bleeding times were obtained, several of whom inherited the Mus castaneous 4.2 allele. From these data we conclude that Ebp4.2 and pa are distinct loci and that changes in protein 4.2 in pallid animals are not directly responsible for the pallid mutation. |
