当前位置： SCI文献检索 > JOURNAL OF CELL SCIENCE期刊下所有文献 > Subcellular localization of GFP-myosin-V in live mouse melanocytes.

Subcellular localization of GFP-myosin-V in live mouse melanocytes.

Abstract：

:Class-V myosins are two-headed actin-based mechanoenzymes that function in the transport and subcellular localization of organelles and possibly in the outgrowth of cellular processes. To determine which domains of myosin-V are involved in intracellular localization of this motor protein, we have expressed fusions of the green fluorescent protein with segments from two distinct myosin-V heavy chains. The expression patterns of constructs encoding four different domains of chick brain myosin-Va were compared to a single construct encoding the globular tail region of mouse myosin-Vb. In transfected mouse melanocytes, expression of the NH(2)-terminal head (catalytic domain) of chick brain myosin-Va codistributed with actin filaments throughout the cytoplasm. A similar construct encoding the myosin-Va head with the associated neck (light chain binding sites), also codistributed with actin filaments. The GFP-head-neck peptide was also highly concentrated in the tips of filopodia in B16 melanocytes wild type for myosin-Va (MYO5a gene), but was concentrated throughout the entire filopodia of S91-6 melanocytes derived from dilute mice with mutations in the MYO5a gene. Evidence is also presented that the globular tail of myosin-Va, but not myosin-Vb, targets this motor molecule to the centrosome as confirmed by colocalization in cells stained with antibodies to (gamma)-tubulin. Expression of the GFP-myosin-Va globular tail causes displacement of endogenous myosin-V from centrosomes as visualized by immunolabeling with antibodies to the head domain of myosin-V. Treatment with the microtubule-disrupting drug nocodazole markedly reduces myosin-V staining at the centrosome. In contrast, there was no detectable diminution of myosin-V staining at the centrosome in cells treated with the actin filament-disrupting drug cytochalasin D. Thus, while localization of the myosin-V motor domain to actin-rich regions is consistent with conventional models of actomyosin-based motility, localization to the centrosome occurs in the complete absence of the myosin-V motor domain and is dependent on intact microtubules.

journal_name

J Cell Sci

journal_title

Journal of cell science

authors

Tsakraklides V,Krogh K,Wang L,Bizario JC,Larson RE,Espreafico EM,Wolenski JS

keywords:

subject

Has Abstract

pub_date

1999-09-01 00:00:00

pages

2853-65

eissn

0021-9533

issn

1477-9137

journal_volume

112 ( Pt 17)

pub_type

杂志文章

在线工具

Subcellular localization of GFP-myosin-V in live mouse melanocytes.