AUTHOR=Meller Barbara , Kuźnicki Daniel , Arasimowicz-Jelonek Magdalena , Deckert Joanna , Floryszak-Wieczorek Jolanta 

TITLE=BABA-Primed Histone Modifications in Potato for Intergenerational Resistance to Phytophthora infestans

JOURNAL=Frontiers in Plant Science

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.01228

DOI=10.3389/fpls.2018.01228

ISSN=1664-462X

ABSTRACT=<p>In this paper we analyzed β-aminobutyric acid (BABA)-primed epigenetic adjustment of potato cv. “Sarpo Mira” to <italic>Phytophthora infestans</italic>. The first stress-free generation of the potato genotype obtained from BABA-primed parent plants via tubers and seeds showed pronounced resistance to the pathogen, which was tuned with the transcriptional memory of SA-responsive genes. During the early priming phase before the triggering stress, we found robust bistable deposition of histone marks (H3K4me2 and H3K27me3) on the <italic>NPR1</italic> (Non-expressor of <italic>PR</italic> genes) and the <italic>SNI1</italic> gene (Suppressor of <italic>NPR1</italic>, Inducible), in which transcription antagonized silencing. Switchable chromatin states of these adverse systemic acquired resistance (SAR) regulators probably reprogrammed responsiveness of the <italic>PR1</italic> and <italic>PR2</italic> genes and contributed to stress imprinting. The elevated levels of heritable H3K4me2 tag in the absence of transcription on SA-dependent genes in BABA-primed (F<sub>0</sub>) and its vegetative and generative progeny (F<sub>1</sub>) before pathogen challenge provided evidence for the epigenetic mark for intergenerational memory in potato. Moreover, our study revealed that histone acetylation was not critical for maintaining BABA-primed defense information until the plants were triggered with the virulent pathogen when rapid and boosted <italic>PR</italic>s gene expression probably required histone acetyltransferase (HAT) activity both in F<sub>0</sub> and F<sub>1</sub> progeny.</p>