A Short Peptide in Rice Glutelin Directs Trafficking of Protein into the Protein Storage Vacuoles of the Endosperm Cells

作者：Li, Wen; Xie, Tingting; Qiu, Qinchuan; Ning, Tingting; Yang, Daichang^*

来源：Plant Molecular Biology Reporter, 2013, 31(6): 1492-1505.

DOI：10.1007/s11105-013-0624-x

• Sequence-specific vacuolar sorting determinant (ssVSD)
• Rice storage protein glutelin
• RMR
• Sorting receptor

Several protein vacuolar sorting determinants (VSDs) have been identified in higher plants. Glutelin as a major storage protein in rice endosperm cells is transported to a protein storage vacuole (PSV). How glutelin sort to PSV and the mechanism of the intracellular trafficking has remained unknown. Here, a sequence-specific vacuolar sorting determinant (ssVSD) is identified by serial deletions of rice glutelin and its role in the protein-sorting process analyzed by transgenic approaches and transient assays. The ssVSD consists of six residues (QRLKHN) within the beta-subunit of glutelin is sufficient to direct the glutelin to the protein body II in the rice endosperm cells. We found that protein-sorting via the ssVSD takes place by a similar to 680-kDa sorting complex containing the receptor Oryza sativa receptor-like membrane Ring-H2 3 (OsRMR3). Further study indicated that OsRMR3 and the ssVSD are essential for glutelin trafficking. Furthermore, site-directed mutagenesis showed that the leucine residues in the ssVSD are critical for protein sorting.

• 出版日期2013-12
• 单位武汉大学