Covalent structures of potato tuber lipases (patatins) and implications for vacuolar import.

ABSTRACT: Proteome data of potato (Solanum tuberosum) tuber juice and of purified potato tuber vacuoles indicated that mature patatins may perhaps lack a C-terminal propeptide. We have confirmed this by complete mass spectrometric sequencing of a number of patatin variants as well as their N-linked complex-type glycans from the starch-rich cultivar Kuras. For this cultivar full-length patatin cDNAs have also been sequenced, as the patatin locus is highly polymorphous. It is well known that patatins are located in the vacuoles of potato tubers. Furthermore, the complex glycan structures show that the path is via the Golgi apparatus. However, the vacuolar targeting signal has never been identified for this storage and defense protein, which amounts to 25-40% of tuber protein. We propose that a six-res

SUBMITTER: Welinder KG 

PROVIDER: S-EPMC2665097 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature