Metabolomic Changes as Key Factors of Green Plant Regeneration Efficiency of Triticale In Vitro Anther Culture

Abstract

Green plant regeneration efficiency (GPRE) via in vitro anther culture results from biochemical pathways and cycle dysfunctions that may affect DNA and histone methylation, with gene expression influencing whole cell functioning. The reprogramming from gametophytic to sporophytic fate is part of the phenomenon. While DNA methylation and sequence changes related to the GPRE have been described, little attention was paid to the biochemical aspects of the phenomenon. Furthermore, only a few theoretical models that describe the complex relationships between biochemical aspects of GPRE and the role of Cu(II) ions in the induction medium and as cofactors of enzymatic reactions have been developed. Still, none of these models are devoted directly to the biochemical level. Fourier transform infrared (FTIR) spectroscopy was used in the current study to analyze triticale regenerants derived under various in vitro tissue culture conditions, including different Cu(II) and Ag(I) ion concentrations in the induction medium and anther culture times. The FTIR spectra of S-adenosyl-L-methionine (SAM), glutathione, and pectins in parallel with the Cu(II) ions, as well as the evaluated GPRE values, were put into the structural equation model (SEM). The data demonstrate the relationships between SAM, glutathione, pectins, and Cu(II) in the induction medium and how they affect GPRE. The SEM reflects the cell functioning under in vitro conditions and varying Cu(II) concentrations. In the presented model, the players are the Krebs and Yang cycles, the transsulfuration pathway controlled by Cu(II) ions acting as cofactors of enzymatic reactions, and the pectins of the primary cell wall.

An insight into tissue culture-induced variation origin shared between anther culture-derived triticale regenerants

“… The 990.950 cm −1 reflects continuous FTIR spectrum starting from 990 and ending at 950 and encompasses values calculated every ten units, the range can be assigned to low methylated pectins (LMP); similarly the 2550 − 2540 cm −1 FTIR reflects data related only to the 10 units range and is assigned to glutathione (GSH), whereas the 1630…1470 cm −1 FTIR range encompasses combined spectra from the given range but the data is not continuous (some ranges were not included into combined variable) [ 28 ], the range is assigned to S-adenosyl-L-methionine (SAM) …”

“…Data from previously published partial structural models of the relationships between CHH_SV, CHH_DNMV, Cu(II), Ag(I), time of anther cultures, β -glucans/pectins, GSH, and GPRE were employed (Ag + [ 30 ], GSH [ 26 ], SAM [ 25 ], GSH and SAM [ 28 ]). Five endogenous variables (described by the model; CHH_DNMV, CHH_SV, FTIR absorbance in the region assigned to SAM, FTIR absorbance in the region assigned to GSH and GPRE) and two exogenous (not described within the model) (FTIR absorbance in the region assigned to LMP, Cu(II)) variables make up the proposed model.…”

“…Furthermore, we have also suggested that the Krebs cycle may also be affected by in vitro tissue culture manipulation [ 28 ]. It was demonstrated that glycolysis could use β -glucans as a carbon source to pump the barley’s TCA cycle [ 38 ].…”

“…Therefore, it was hypothesized that it might have a biochemical background. A series of studies conducted on barley and triticale demonstrated that S-adenosyl-L-methionine (SAM) [ 25 ], glutathione (GSH) [ 26 ], b -glucans [ 27 ]/pectins [ 28 ], and Cu(II) ions [ 22 ] are involved in GPRE. The metabolites, via structural equation models [ 28 ], were linked to the Krebs and Yang cycles and biochemical pathways, including glycolysis or transsulfuration.…”

“…A series of studies conducted on barley and triticale demonstrated that S-adenosyl-L-methionine (SAM) [ 25 ], glutathione (GSH) [ 26 ], b -glucans [ 27 ]/pectins [ 28 ], and Cu(II) ions [ 22 ] are involved in GPRE. The metabolites, via structural equation models [ 28 ], were linked to the Krebs and Yang cycles and biochemical pathways, including glycolysis or transsulfuration. However, no generalized scheme linking the metabolome, TCIV and GPRE has been evaluated, including triticale.…”