In:
Molecular Biology of the Cell, American Society for Cell Biology (ASCB), Vol. 16, No. 12 ( 2005-12), p. 5592-5609
Abstract:
Specific changes in membrane lipid composition are implicated in actin cytoskeletal organization, vesicle formation, and control of cell polarity. Cdc50p, a membrane protein in the endosomal/trans-Golgi network compartments, is a noncatalytic subunit of Drs2p, which is implicated in translocation of phospholipids across lipid bilayers. We found that the cdc50Δ mutation is synthetically lethal with mutations affecting the late steps of ergosterol synthesis (erg2 to erg6). Defects in cell polarity and actin organization were observed in the cdc50Δ erg3Δ mutant. In particular, actin patches, which are normally found at cortical sites, were assembled intracellularly along with their assembly factors, including Las17p, Abp1p, and Sla2p. The exocytic SNARE Snc1p, which is recycled by an endocytic route, was also intracellularly accumulated, and inhibition of endocytic internalization suppressed the cytoplasmic accumulation of both Las17p and Snc1p. Simultaneous loss of both phospholipid asymmetry and sterol structural integrity could lead to accumulation of endocytic intermediates capable of initiating assembly of actin patches in the cytoplasm.
Type of Medium:
Online Resource
ISSN:
1059-1524
,
1939-4586
DOI:
10.1091/mbc.e05-05-0452
Language:
English
Publisher:
American Society for Cell Biology (ASCB)
Publication Date:
2005
detail.hit.zdb_id:
1474922-1
SSG:
12
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