Localization of myosin-V in the centrosome

Localization of myosin-V in the centrosome

^†Laboratory of Cellular Biology, Section on Structural Cell Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892-4163; ^*Department of Morphology, FMRP-USP, Ribeirão Preto, SP, 14049–900, Brazil; and ^‡Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511

Communicated by Thomas S. Reese, National Institutes of Health, Bethesda, MD (received for review February 27, 1998)

Abstract

The perinuclear localization of myosin-V was investigated in a variety of cultured mammalian cells and in primary cultures of rat hippocampus. In all cells investigated, myosin-V immunoreactivity was associated with the centrosome. In interphase cells, myosin-V was found in pericentriolar material, and in both mother and daughter centrioles. These results were obtained by using two different fixation protocols with three different affinity-purified antibodies that recognized a single band in Western blots. During cell division, myosin-V staining was intense throughout the cytoplasm and was concentrated in a trail between migrating centrioles and in the mitotic spindle poles and spindle fibers. The centrosome targeting site was determined to reside within the globular tail domain, because centrosome association also was observed in living cells transfected with DNA encoding the tail domain fused with a green fluorescent protein tag, but not in cells transfected with the vector encoding green fluorescent protein by itself.

mitotic spindle

Footnotes

↵ § To whom reprint requests should be addressed at: Section on Structural Cell Biology, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Building 36, Room 5D15, MSC 4163, Bethesda, MD 20892-4163. e-mail: kachar{at}pop.nidcd.nih.gov.
ABBREVIATION:

GFP,

green fluorescent protein