Premium
RACK 1 scaffold proteins influence mi RNA abundance in Arabidopsis
Author(s) -
Speth Corinna,
Willing EvaMaria,
Rausch Stephanie,
Schneeberger Korbinian,
Laubinger Sascha
Publication year - 2013
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1111/tpj.12308
Subject(s) - arabidopsis , microrna , arabidopsis thaliana , microbiology and biotechnology , biology , scaffold protein , mutant , computational biology , gene , genetics , signal transduction
Summary 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 to facilitate efficient and precise pri‐miRNA processing and miRNA loading, respectively. In this study, we show that the accumulation of plant microRNAs depends on RECEPTOR FOR ACTIVATED C KINASE 1 (RACK1), a scaffold protein that is 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 over‐accumulation of miRNA target mRNA s, which are important for ABA responses and phyllotaxy, for example. In conclusion, our study identified complex functioning of RACK1 proteins in the Arabidopsis miRNA pathway; these proteins are important for miRNA production and therefore plant development.