RRC ID 1876
Author Raab S, Toth Z, de Groot C, Stamminger T, Hoth S.
Title ABA-responsive RNA-binding proteins are involved in chloroplast and stromule function in Arabidopsis seedlings.
Journal Planta
Abstract The phytohormone abscisic acid (ABA) regulates essential growth and developmental processes in plants. Recently, RNA-binding proteins have been described as components of ABA signaling during germination. We have identified ten ABA-regulated RNA-binding proteins in Arabidopsis seedlings. Among those genes, AtCSP41B and cpRNP29 are highly expressed in seedlings. Using promoter:reporter gene analyses, we showed that both AtCSP41B and cpRNP29 were in particular expressed in photosynthetically active organs like green cotyledons, leaves, and petioles. The analysis of CFP-fusion proteins demonstrates that cpRNP29 localized to chloroplasts and AtCSP41B to chloroplasts and stromules. Whereas RNA-binding of cpRNP29 has previously been shown, we demonstrated through in vitro RNA-binding assays that recombinant AtCSP41B binds to RNA, and that chloroplast petD RNA can serve as a target of AtCSP41B. Developmental or environmental stimuli affected the expression of AtCSP41B and cpRNP29 in seedlings. Both genes were repressed during senescence, but only AtCSP41B was significantly repressed upon water stress. In addition, AtCSP41B and cpRNP29 exhibited low expression in etiolated seedlings compared to green seedlings, and cpRNP29 was regulated during the day photoperiod. Homozygous T-DNA insertion lines were isolated, characterized on the molecular level, and monitored for phenotypic changes. Taken together, the data show that both proteins are regulated during processes that are known to involve ABA signaling. Their localization in chloroplasts and RNA-binding activity suggest a role in chloroplast RNA metabolism in Arabidopsis seedlings.
Volume 224(4)
Pages 900-14
Published 2006-9
DOI 10.1007/s00425-006-0282-4
PMID 16633814
MeSH Abscisic Acid / physiology* Aging / metabolism Arabidopsis / physiology* Chloroplasts / physiology* DNA, Bacterial DNA, Chloroplast / metabolism Gene Expression Regulation, Plant Genes, Reporter Mutagenesis, Insertional Photoperiod Plants, Genetically Modified Promoter Regions, Genetic RNA, Chloroplast / metabolism RNA-Binding Proteins / physiology* Seedlings / physiology* Water / metabolism
IF 3.249
Times Cited 29
Arabidopsis / Cultured plant cells, genes pda06657 pda00754