First Author | Nascimento AA | Year | 1997 |
Journal | Mol Biol Cell | Volume | 8 |
Issue | 10 | Pages | 1971-88 |
PubMed ID | 9348537 | Mgi Jnum | J:117769 |
Mgi Id | MGI:3697560 | Doi | 10.1091/mbc.8.10.1971 |
Citation | Nascimento AA, et al. (1997) Subcellular localization of myosin-V in the B16 melanoma cells, a wild-type cell line for the dilute gene. Mol Biol Cell 8(10):1971-88 |
abstractText | The discovery that the dilute gene encodes a class V myosin led to the hypothesis that this molecular motor is involved in melanosome transport and/or dendrite outgrowth in mammalian melanocytes. The present studies were undertaken to gain insight into the subcellular distribution of myosin-V in the melanoma cell line B16-F10, which is wild-type for the dilute gene. Immunofluorescence studies showed some degree of superimposed labeling of myosin-V with melanosomes that predominated at the cell periphery. A subcellular fraction highly enriched in melanosomes was also enriched in myosin-V based on Western blot analysis. Immunoelectron microscopy showed myosin-V labeling associated with melanosomes and other organelles. The stimulation of B16 cells with the alpha-melanocyte-stimulating hormone led to a significant increase in myosin-V expression. This is the first evidence that a cAMP signaling pathway might regulate the dilute gene expression. Immunofluorescence also showed an intense labeling of myosin-V independent of melanosomes that was observed within the dendrites and at the perinuclear region. Although the results presented herein are consistent with the hypothesis that myosin-V might act as a motor for melanosome translocation, they also suggest a broader cytoplasmic function for myosin-V, acting on other types of organelles or in cytoskeletal dynamics. |