Lipid droplet-associated gene expression and chromatin remodelling in LIPASE 5′-upstream region from beginning- to mid-endodormant bud in ‘Fuji’ apple
We found that lipid accumulation in the meristem region and the expression of MdLIP2A, which appears to be regulated by chromatin remodeling, coincided with endodormancy induction in the ‘Fuji’ apple.
In deciduous trees, including apples (Malus × domestica Borkh.), lipid accumulation in the meristem region towards endodormancy induction has been thought to be an important process for the acquisition of cold tolerance. In this study, we conducted histological staining of crude lipids in the meristem region of ‘Fuji’ apples and found that lipid accumulation coincided with endodormancy induction. Since a major component of lipid bodies (triacylglycerol) is esterified fatty acids, we analysed fatty acid-derived volatile compounds and genes encoding fatty acid-modifying enzymes (MdLOX1A and MdHPL2A); the reduction of lipid breakdown also coincided with endodormancy induction. We then characterised the expression patterns of lipid body-regulatory genes MdOLE1 and MdLIP2A during endodormancy induction and found that the expression of MdLIP2A correlated well with lipid accumulation towards endodormancy induction. Based on these results, we conducted chromatin remodelling studies and localized the cis-element in the 5′-upstream region of MdLIP2A to clarify its regulatory mechanism. Finally, we revealed that chromatin was concentrated − 764 to − 862 bp of the 5′-upstream region of MdLIP2A, which harbours the GARE [gibberellin responsive MYB transcription factor binding site] and CArG [MADS-box transcription factor binding site] motifs—meristem development-related protein-binding sites.
KeywordsCHART-PCR Chromatin remodelling Endodormancy induction Lipid body
MADS-box transcription factor-binding site
Elongation factor 1
FLOWERING LOCUS T
Gibberellin-responsive MYB transcription factor-binding site
Genome Database for Rosaceae
National Center for Biotechnology Information
Quantitative trait locus
This work was supported by the Program to Disseminate Tenure Tracking System from the Japanese Ministry of Education, Culture, Sports, Science and Technology, and by a grant from the Chiba University to TS.
TS designed the study and wrote paper, WS and YO performed and supervised the microscopy experiments, respectively, HI performed GC/MS analysis, OK, HO, and SK revised the article and corrected the content.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest with the contents of this article.
- Allard A, Bink MC, Martinez S, Kelner JJ, Legave JM, di Guardo M, di Pierro EA, Laurens F, van de Weg EW, Costes E (2016) Detecting QTLs and putative candidate genes involved in budbreak and flowering time in an apple multiparental population. J Exp Bot 67:2875–2888CrossRefPubMedPubMedCentralGoogle Scholar
- Faust M, Erez A, Rowland LJ, Wang SY, Norman HA (1997) Bud dormancy in perennial fruit trees: physiological basis for dormancy induction, maintenance and release. HortScience 32:623–629Google Scholar
- Kuroda H, Sagisaka S (1993) Ultrastructural changes in cortical cells of apple (Malus pumila Mill.) associated with cold hardiness. Plant Cell Physiol 34:357–365Google Scholar
- Lang GA (1987) Dormancy: a new universal terminology. HortScience 22:817–820Google Scholar
- Liu D, Norman HA, Stutte GW, Faust M (1991) Lipase activity during endodormancy in leaf buds of apple. J Am Soc Hortic Sci 116:689–692Google Scholar
- Nakashima A, von Reuss SH, Tasaka H, Nomura M, Mochizuki S, Iijima Y, Aoki K, Shibata D, Boland M, Takabayashi J, Matsui K (2013) Traumatin-and dinortraumatin-containing galactolipids in arabidopsis their formation in tissue-disrupted leaves as counterparts of green leaf volatiles. J Biol Chem 9:274–280Google Scholar
- Rinne PL, Welling A, Vahala J, Ripel L, Ruonala R, Kangasjärvi J, van der Schoot C (2011) Chilling of dormant buds hyperinduces FLOWERING LOCUS T and recruits GA-inducible 1, 3-β-glucanases to reopen signal conduits and release dormancy in Populus. Plant Cell 23:130–146CrossRefPubMedPubMedCentralGoogle Scholar
- Sakamoto D, Nakamura Y, Sugiura H, Sugiura T, Asakura T, Yokoyama M, Moriguchi T (2010) Effect of 9-hydroxy-10-oxo-12 (Z), 15 (Z)-octadecadienoic acid (KODA) on endodormancy breaking in flower buds of Japanese pear. HortScience 45:1470–1474Google Scholar
- Saure MC (1985) Dormancy release in deciduous fruit trees. Hortic Rev 7:239–300Google Scholar
- Wang SY, Faust M (1990) Changes of membrane lipids in apple buds during dormancy and budbreak. J Am Soc Hortic Sci 115:803–808Google Scholar