Molecular Genetics and Genomics

, Volume 271, Issue 2, pp 197–207

Characterization of Schizosaccharomyces pombe mutants defective in vacuolar acidification and protein sorting

Original Paper

DOI: 10.1007/s00438-003-0971-7

Cite this article as:
Iwaki, T., Goa, T., Tanaka, N. et al. Mol Genet Genomics (2004) 271: 197. doi:10.1007/s00438-003-0971-7

Abstract

The vacuolar H+-ATPases (V-ATPases) are ATP-dependent proton pumps responsible for acidification of intracellular compartments in eukaryotic cells. To investigate the functional roles of the V-ATPase in Schizosaccharomyces pombe, the gene vma1 encoding subunit A or vma3 encoding subunit c was disrupted. Both deletion mutants lost the capacity for vacuolar acidification in vivo, and showed sensitivity to neutral pH or high concentrations of divalent cations including Ca2+. The delivery of FM4-64 to the vacuolar membrane and accumulation of Lucifer Yellow CH were strongly inhibited in the vma1 and vma3 mutants. Moreover, deletion of the S. pombe vma1+ or vma3+ gene resulted in pleiotropic phenotypes consistent with lack of vacuolar acidification, including the missorting of vacuolar carboxypeptidase Y, abnormal vacuole morphology, and mating defects. These findings suggest that V-ATPase is essential for endocytosis, ion and pH homeostasis, and for intracellular targeting of vacuolar proteins and vacuolar biogenesis in S. pombe.

Keywords

V-ATPaseCarboypeptidase Y (CPY)Vacuolar protein sortingEndocytosisFission yeast

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  1. 1.Department of Life Sciences, Faculty of AgricultureKagawa UniversityMiki-choJapan
  2. 2.Research CenterAsahi Glass Co. Ltd.YokohamaJapan