Chromatin assembly factor 1 ensures the stable maintenance of silent chromatin states in Arabidopsis.
Newly synthesized DNA is rapidly assembled into mature nucleosomes by the deposition of pre-existing and nascent histones, and some parts of this process are facilitated by chromatin assembly factor 1 (CAF-1). Loss-of-function mutants of CAF-1 in Arabidopsis, fasciata (fas), show a variety of morphological abnormalities and unique defects in gene expression in the meristems. In order to clarify the implications of CAF-1 in the maintenance of chromatin states in higher eukaryotes, we investigated transcriptional gene silencing (TGS) of various genes in fas mutants. Here, we show that TGS of endogenous CACTA transposons was released in a stochastic manner in fas. Other endogenous silent genes, a transposon AtMu1 and a hypothetical gene T5L23.26 at a heterochromatin knob, were also transcriptionally activated, and the activation of the three different silent loci at different chromosomal sites occurred non-concomitantly with each other. Furthermore, TGS of the silent beta-glucuronidase (GUS) transgene was also de-repressed randomly in fas. We conclude that CAF-1 ensures the stable inheritance of epigenetic states through growth and development in Arabidopsis.
Ono
Tatsuya
T
Department of Integrated Genetics, National Institute of Genetics, Mishima 411-8540, Japan.
Kaya
Hidetaka
H
Takeda
Shin
S
Abe
Mitsutomo
M
Ogawa
Yuya
Y
Kato
Masaomi
M
Kakutani
Tetsuji
T
Mittelsten Scheid
Ortrun
O
Araki
Takashi
T
Shibahara
Kei-ichi
K
D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002843:Chromatin / Q000235:genetics* / Q000378:metabolism*; D056504:Chromatin Assembly Factor-1; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D032461:Chromosomes, Plant / Q000235:genetics; D004251:DNA Transposable Elements / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D005966:Glucuronidase / Q000235:genetics; D018519:Meristem / Q000166:cytology; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D018515:Plant Leaves / Q000166:cytology; D018517:Plant Roots / Q000033:anatomy & histology / Q000166:cytology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000033:anatomy & histology / Q000235:genetics; D013269:Stochastic Processes; D014158:Transcription, Genetic; D015533:Transcriptional Activation / Q000235:genetics; D019076:Transgenes
D029681:Arabidopsis Proteins; D002843:Chromatin; D056504:Chromatin Assembly Factor-1; D002868:Chromosomal Proteins, Non-Histone; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; C422044:FAS protein, Arabidopsis; D012333:RNA, Messenger; D005966:Glucuronidase