ABSTRACT
Fruit development, following pollination, involves a cell division stage, followed by cell expansion . A major challenges to study each individual stages is the limitations imposed by analyses of fruit development on the plant. Rapid growing cell culture systems that differentiate could be used to identify and understand the molecular control of each of these processes in vitro. In this study, an apple cell culture was initiated from the widely characterised ‘Royal Gala’ cultivar. The established apple cell culture was used to develop a screening system to assess the effect of different hormones on cell differentiation, which then were characterised at molecular and cellular levels. Three different hormone pairs were screened to determine the optimal for cell expansion on actively dividing cells . Using this strategy, we were able to reproduce, in vitro, the first two stages of apple fruit cell differentiation, cell division and expansion, which was correlated with changes in genes expression of specific markers for those two stages, a cyclin-dependent kinase gene (CDKB2;2) and an expansion gene (EXP3). The cell culture provides a unique tool and opportunity to study the effect of plant hormones on cell differentiation and will allow to decipher the molecular mechanism of apple fruit development irrespective of y.
Acknowledgments
This research was funded by the University of Auckland and the Plant and Food Research Ltd. SK was a recipient of a PhD fellowship from the Malaysian Ministry of Education (MoE).
Author’s contributions
SK developed the all the methodology and NR contributed to the 24 well-plate screenings. The data were analysed by SK, RS and KD. The manuscript was written by SK, RS, KD and AA.
Abbreviations
2,4-D | = | 2,4-dichlorophenoxyacetic acid |
BAP | = | 6-benzylaminopurine |
NAA | = | 1-naphthaleneacetic acid |
GA3 | = | Gibberellin |
MS | = | Murashige and Skoog’s mineral solution |
qPCR | = | Quantitative real-time PCR |
DAFB | = | Days After Full Bloom |
Disclosure statement
No potential conflict of interest was reported by the author(s).
Highlights
An apple ‘Royal Gala’ liquid cell culture was successfully established and maintained.
The first two stages of apple fruit cell differentiation, cell division and expansion, were induced in vitro by different combinations of auxin, cytokinins and gibberellins.
The cell expansion response is not solely linked to a specific cytokinin/auxin or gibberellin/auxin ratio but is highly dependent on individual concentrations of each hormone.
Supplementary material
Supplemental data for this article can be accessed here.