Two isoforms of Npap60 (Nup50) differentially regulate nuclear protein import.
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ABSTRACT:
SUBMITTER: Ogawa Y
PROVIDER: S-EPMC2820426 | biostudies-other | 2010 Feb
REPOSITORIES: biostudies-other
Publications
Two isoforms of Npap60 (Nup50) differentially regulate nuclear protein import.
Ogawa Yutaka Y Miyamoto Yoichi Y Asally Munehiro M Oka Masahiro M Yasuda Yoshinari Y Yoneda Yoshihiro Y
Molecular biology of the cell 20091216 4
Npap60 (Nup50) is a nucleoporin that binds directly to importin alpha. In humans, there are two Npap60 isoforms: the long (Npap60L) and short (Npap60S) forms. In this study, we provide both in vitro and in vivo evidence that Npap60L and Npap60S function differently in nuclear protein import. In vitro binding assays revealed that Npap60S stabilizes the binding of importin alpha to classical NLS-cargo, whereas Npap60L promotes the release of NLS-cargo from importin alpha. In vivo time-lapse experi ...[more]
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