Reduced seed germination in Arabidopsis over-expressing SWI/SNF2 ATPase genes.
In the life of flowering plants, seed germination is a critical step to ensure survival into the next generation. Generally the seed prior to germination has been in a dormant state with a low rate of metabolism. In the transition from a dormant seed to a germinating seed, various epigenetic mechanisms play a regulatory role. Here, we demonstrate that the over-expression of chromatin remodeling ATPase genes (AtCHR12 or AtCHR23) reduced the frequency of seed germination in Arabidopsis thaliana up to 30% relative to the wild-type seeds. On the other hand, single loss-of-function mutations of the two genes did not affect seed germination. The reduction of germination in over-expressing mutants was more pronounced in stress conditions (salt or high temperature), showing the impact of the environment. Reduced germinations upon over-expression coincided with increased transcript levels of seed maturation genes and with reduced degradation of their mRNAs stored in dry seeds. Our results indicate that repression of AtCHR12/23 gene expression in germinating wild-type Arabidopsis seeds is required for full germination. This establishes a functional link between chromatin modifiers and regulatory networks towards seed maturation and germination.
Laboratory of Molecular Biology, Plant Sciences Group, Wageningen University and Research Centre, Wageningen, The Netherlands.
Hendrika A C F
HA
Leeggangers
Adam
A
Folta
Aleksandra
A
Muras
Jan-Peter
JP
Nap
Ludmila
L
Mlynarova
D000040:Abscisic Acid / Q000494:pharmacology; D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D042002:Chromatin Assembly and Disassembly / Q000187:drug effects / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D018525:Germination / Q000187:drug effects / Q000235:genetics*; D010641:Phenotype; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012639:Seeds / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000235:genetics; D013696:Temperature; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D029681:Arabidopsis Proteins; C525258:CHR12 protein, Arabidopsis; D012333:RNA, Messenger; D014157:Transcription Factors; D012965:Sodium Chloride; D000040:Abscisic Acid; D000251:Adenosine Triphosphatases; C000593362:CHR23 protein, Arabidopsis