Speth C, Willing EM, Rausch S, Schneeberger K, Laubinger S

MicroRNAs (miRNAs) regulate plant development by post-transcriptional regulation of target genes. In Arabidopsis thaliana, DCL1 processes precursors (pri-miRNAs) to miRNA duplexes, which associate with AGO1. Additional proteins act in concert with DCL1 (e.g. HYL1 and SERRATE) or AGO1, respectively, to facilitate efficient and precise pri-miRNA processing and miRNA loading. In ...

Read More

this study, we show that the accumulation of plant microRNAs depends on RECEPTOR FOR ACTIVATED C KINASE 1 (RACK1), a scaffold protein found in all higher eukaryotes. miRNA levels are reduced in rack1 mutants and our data suggest that RACK1 affects the microRNA pathway via several distinct mechanisms involving direct interactions with known microRNA factors: RACK1 ensures the accumulation and processing of some pri-miRNAs, directly interacts with SERRATE and is part of an AGO1 complex. As a result, mutations in RACK1 lead to an overaccumulation of miRNA target mRNAs, which are important for e.g. ABA responses and phyllotaxy. In conclusion, our study discovered complex functioning of RACK1 proteins in the Arabidopsis miRNA pathway, which are important for miRNA production and therefore plant development. MPI for Developmental Biology.

Date: Aug. 13, 2013

View in: Pubmed Google Scholar

157865