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A new pathway for protein export in Saccharomyces cerevisiae.

ABSTRACT: Several physiologically important proteins lack a classical secretory signal sequence, yet they are secreted from cells. To investigate the secretion mechanism of such proteins, a representative mammalian protein that is exported by a nonclassical mechanism, galectin-1, has been expressed in yeast. Galectin-1 is exported across the yeast plasma membrane, and this export does not require the classical secretory pathway nor the yeast multidrug resistance-like protein Ste6p, the transporter for the peptide a factor. A screen for components of the export machinery has identified genes that are involved in nonclassical export. These findings demonstrate a new pathway for protein export that is distinct from the classical secretory pathway in yeast.

SUBMITTER: Cleves AE

PROVIDER: S-EPMC2120850 | biostudies-other | 1996 Jun

REPOSITORIES: biostudies-other

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A new pathway for protein export in Saccharomyces cerevisiae.

Cleves A E AE Cooper D N DN Barondes S H SH Kelly R B RB

The Journal of cell biology 19960601 5

Several physiologically important proteins lack a classical secretory signal sequence, yet they are secreted from cells. To investigate the secretion mechanism of such proteins, a representative mammalian protein that is exported by a nonclassical mechanism, galectin-1, has been expressed in yeast. Galectin-1 is exported across the yeast plasma membrane, and this export does not require the classical secretory pathway nor the yeast multidrug resistance-like protein Ste6p, the transporter for the ...[more]

PMID: 8655575

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