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Updated: Nov 3, 2025

Studying Protein Import into Chloroplasts Using Protoplasts
Published on: December 10, 2018
Functions of plant importin β proteins beyond nucleocytoplasmic transport
Feng Xiong1, Edwin P Groot2, Yan Zhang1
1State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, China.
Abstract:
In eukaryotic cells, nuclear activities are isolated from other cellular functions by the nuclear envelope. Because the nuclear envelope provides a diffusion barrier for macromolecules, a complex nuclear transport machinery has evolved that is highly conserved from yeast to plants and mammals. Among those components, the importin β family is the most important one. In this review, we summarize recent findings on the biological function of importin β family members, including development, reproduction, abiotic stress responses, and plant immunity. In addition to the traditional nuclear transport function, we highlight the new molecular functions of importin β, including protein turnover, miRNA regulation, and signaling. Taken together, our review will provide a systematic view of this versatile protein family in plants.
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