Arabidopsis Argonaute10 specifically sequesters miR166/165 to regulate shoot apical meristem development.
- Additional Document Info
- View All
The shoot apical meristem (SAM) comprises a group of undifferentiated cells that divide to maintain the plant meristem and also give rise to all shoot organs. SAM fate is specified by class III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP III) transcription factors, which are targets of miR166/165. In Arabidopsis, AGO10 is a critical regulator of SAM maintenance, and here we demonstrate that AGO10 specifically interacts with miR166/165. The association is determined by a distinct structure of the miR166/165 duplex. Deficient loading of miR166 into AGO10 results in a defective SAM. Notably, the miRNA-binding ability of AGO10, but not its catalytic activity, is required for SAM development, and AGO10 has a higher binding affinity for miR166 than does AGO1, a principal contributor to miRNA-mediated silencing. We propose that AGO10 functions as a decoy for miR166/165 to maintain the SAM, preventing their incorporation into AGO1 complexes and the subsequent repression of HD-ZIP III gene expression.
author list (cited authors)
Zhu, H., Hu, F., Wang, R., Zhou, X., Sze, S., Liou, L. W., ... Zhang, X.
complete list of authors
Zhu, Hongliang||Hu, Fuqu||Wang, Ronghui||Zhou, Xin||Sze, Sing-Hoi||Liou, Lisa Wen||Barefoot, Ashley||Dickman, Martin||Zhang, Xiuren