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Endoplasmic reticulum retention signal-dependent glycylation of the Hsp70/Grp170-related Pgp1p in Tetrahymena.

ABSTRACT: Glycylation is an uncommon posttranslational modification. It has been found that tubulin glycylation is essential for cell survival in Tetrahymena. Here we describe PGP1, a Tetrahymena gene encoding an Hsp70 homologue that is a novel glycylated protein. Pgp1p is a conserved glycoprotein that localizes within the lumen of the endoplasmic reticulum (ER). We demonstrate that PGP1 is essential for viability and present evidence that both glycosylation and ER retention are necessary but not sufficient for glycylation.

SUBMITTER: Xie R

PROVIDER: S-EPMC1828932 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature

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Endoplasmic reticulum retention signal-dependent glycylation of the Hsp70/Grp170-related Pgp1p in Tetrahymena.

Xie Rong R Clark Kathleen M KM Gorovsky Martin A MA

Eukaryotic cell 20061222 3

Glycylation is an uncommon posttranslational modification. It has been found that tubulin glycylation is essential for cell survival in Tetrahymena. Here we describe PGP1, a Tetrahymena gene encoding an Hsp70 homologue that is a novel glycylated protein. Pgp1p is a conserved glycoprotein that localizes within the lumen of the endoplasmic reticulum (ER). We demonstrate that PGP1 is essential for viability and present evidence that both glycosylation and ER retention are necessary but not sufficie ...[more]

PMID: 17189490

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