title: The Rice Eukaryotic Translation Initiation Factor 3 Subunit e (OseIF3e) Influences Organ Size and Pollen Maturation.
abstract: Eukaryotic translation initiation factor 3 (eIF3) is a large protein complex that participates in most translation initiation processes. While eIF3 has been well characterized, less is known about the roles of individual eIF3 subunits, particularly in plants. Here, we identified and characterizedOseIF3ein rice (Oryza sativaL.).OseIF3ewas constitutively expressed in various tissues, but most strongly in vigorously growing organs. TransgenicOseIF3e-silenced rice plants showed inhibited growth in seedling and vegetative stages. Repression ofOseIF3eled to defects in pollen maturation but did not affect pollen mitosis. In rice, eIF3e interacted with eIF3 subunits b, d, e, f, h, and k, and with eIF6, forming homo- and heterodimers to initiate translation. Furthermore, OseIF3e was shown by yeast two-hybrid assay to specifically bind to inhibitors of cyclin-dependent kinases 1, 5, and 6. This interaction was mediated by the sequence of amino acid residues at positions 118-138, which included a conserved motif (IGPEQIETLYQFAKF). These results suggested although OseIF3e is not a "functional core" subunit of eIF3, it still plays crucial roles in rice growth and development, in combination with other factors. We proposed a pathway by whichOseIF3einfluence organ size and pollen maturation in rice, providing an opportunity to optimize plant architecture for crop breeding.
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University Hangzhou, China.
authors.forename: Wenyi
authors.initials: W
authors.lastname: Wang
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University Hangzhou, China.
authors.forename: Mengyun
authors.initials: M
authors.lastname: Xu
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University Hangzhou, China.
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Liu
authors.affiliation: Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University Hangzhou, China.
authors.forename: Jumin
authors.initials: J
authors.lastname: Tu
keywords: Oryza sativa L.; OsICKs; OseIF3e; pollen maturation; reproductive development; translation initiation