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Hop-on hop-off: importin-?-guided tours to the nucleus in innate immune signaling.

ABSTRACT: Nuclear translocation of immune regulatory proteins and signal transducers is an essential process in animal and plant defense signaling against pathogenic microbes. Import of proteins containing a nuclear localization signal (NLS) into the nucleus is mediated by nuclear transport receptors termed importins, typically dimers of a cargo-binding ?-subunit and a ?-subunit that mediates translocation through the nuclear pore complex. Here, we review recent reports of importin-? cargo specificity and mutant phenotypes in plant- and animal-microbe interactions. Using homology modeling of the NLS-binding cleft of nine predicted Arabidopsis ?-importins and analyses of their gene expression patterns, we discuss functional redundancy and specialization within this transport receptor family. In addition, we consider how pathogen effector proteins that promote infection by manipulating host cell nuclear processes might compete with endogenous cargo proteins for nuclear uptake.

SUBMITTER: Wirthmueller L

PROVIDER: S-EPMC3659281 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Hop-on hop-off: importin-α-guided tours to the nucleus in innate immune signaling.

Wirthmueller Lennart L Roth Charlotte C Banfield Mark J MJ Wiermer Marcel M

Frontiers in plant science 20130521

Nuclear translocation of immune regulatory proteins and signal transducers is an essential process in animal and plant defense signaling against pathogenic microbes. Import of proteins containing a nuclear localization signal (NLS) into the nucleus is mediated by nuclear transport receptors termed importins, typically dimers of a cargo-binding α-subunit and a β-subunit that mediates translocation through the nuclear pore complex. Here, we review recent reports of importin-α cargo specificity and ...[more]

PMID: 23734157

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