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Btn1 affects endocytosis, polarization of sterol-rich membrane domains and polarized growth in Schizosaccharomyces pombe.

ABSTRACT: btn1, the Schizosaccharomyces pombe orthologue of the human Batten disease gene CLN3, exerts multiple cellular effects. As well as a role in vacuole pH homoeostasis, we now show that Btn1p is essential for growth at high temperatures. Its absence results in progressive defects at 37 degrees C that culminate in total depolarized growth and cell lysis. These defects are preceded by a progressive failure to correctly polarize sterol-rich domains after cytokinesis and are accompanied by loss of Myo1p localization. Furthermore, we found that in Sz. pombe, sterol spreading is linked to defective formation/polarization of F-actin patches and disruption of endocytosis and that these processes are aberrant in btn1Delta cells. Consistent with a role for Btn1p in polarized growth, Btn1p has an altered location at 37 degrees C and is retained in actin-dependent endomembrane structures near the cell poles or septum.

SUBMITTER: Codlin S

PROVIDER: S-EPMC2440566 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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btn1 affects endocytosis, polarization of sterol-rich membrane domains and polarized growth in Schizosaccharomyces pombe.

Codlin Sandra S Haines Rebecca L RL Mole Sara E SE

Traffic (Copenhagen, Denmark) 20080310 6

btn1, the Schizosaccharomyces pombe orthologue of the human Batten disease gene CLN3, exerts multiple cellular effects. As well as a role in vacuole pH homoeostasis, we now show that Btn1p is essential for growth at high temperatures. Its absence results in progressive defects at 37 degrees C that culminate in total depolarized growth and cell lysis. These defects are preceded by a progressive failure to correctly polarize sterol-rich domains after cytokinesis and are accompanied by loss of Myo1 ...[more]

PMID: 18346214

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