Limits...
Distribution of lipid transfer protein 1 (LTP1) epitopes associated with morphogenic events during somatic embryogenesis of Arabidopsis thaliana.

Potocka I, Baldwin TC, Kurczynska EU - Plant Cell Rep. (2012)

Bottom Line: The labelling was strongest in both the outer periclinal and anticlinal walls of the adaxial, protodermal cells of the proximal region of the cotyledon.The putative role(s) of lipid transfer proteins in the formation of lipid lamellae and in cell differentiation are discussed.Key message Occurrence of lipid transfer protein 1 epitopes in Arabidopsis explant cells accompanies changes in cell fate and may be correlated with the deposition of lipid substances in the cell walls.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Cell Biology, University of Silesia, Jagiellońska 28, 40-032, Katowice, Poland. izabela.potocka@us.edu.pl

ABSTRACT
Using immunocytochemical methods, at both the light and electron microscopic level, we have investigated the spatial and temporal distribution of lipid transfer protein 1 (LTP1) epitopes during the induction of somatic embryogenesis in explants of Arabidopsis thaliana. Immunofluorescence labelling demonstrated the presence of high levels of LTP1 epitopes within the proximal regions of the cotyledons (embryogenic regions) associated with particular morphogenetic events, including intense cell division activity, cotyledon swelling, cell loosening and callus formation. Precise analysis of the signal localization in protodermal and subprotodermal cells indicated that cells exhibiting features typical of embryogenic cells were strongly labelled, both in walls and the cytoplasm, while in the majority of meristematic-like cells no signal was observed. Staining with lipophilic dyes revealed a correlation between the distribution of LTP1 epitopes and lipid substances within the cell wall. Differences in label abundance and distribution between embryogenic and non-embryogenic regions of explants were studied in detail with the use of immunogold electron microscopy. The labelling was strongest in both the outer periclinal and anticlinal walls of the adaxial, protodermal cells of the proximal region of the cotyledon. The putative role(s) of lipid transfer proteins in the formation of lipid lamellae and in cell differentiation are discussed. Key message Occurrence of lipid transfer protein 1 epitopes in Arabidopsis explant cells accompanies changes in cell fate and may be correlated with the deposition of lipid substances in the cell walls.

Show MeSH

Related in: MedlinePlus

Immunogold localization of LTP1 epitopes in the cell walls and cytoplasm of the explants. a Callus cell from an explant cultured for 21 days, notice densely and uniformly labelled cell wall, the asterisk marks the cell interior. b Tricellular junction with intercellular space formed between the adaxial protodermal and subprotodermal cells of the cotyledon, day 4 of culture. c Intracellular localization of LTP1 epitopes, adaxial protodermal cell of the cotyledon, day 7 of culture. d Negative control, no labelling visible. CW cell wall, ER endoplasmic reticulum, IS intercellular space, V vacuole. Scale bars 100 nm (a, c, d), 200 nm (b)
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3472069&req=5

Fig8: Immunogold localization of LTP1 epitopes in the cell walls and cytoplasm of the explants. a Callus cell from an explant cultured for 21 days, notice densely and uniformly labelled cell wall, the asterisk marks the cell interior. b Tricellular junction with intercellular space formed between the adaxial protodermal and subprotodermal cells of the cotyledon, day 4 of culture. c Intracellular localization of LTP1 epitopes, adaxial protodermal cell of the cotyledon, day 7 of culture. d Negative control, no labelling visible. CW cell wall, ER endoplasmic reticulum, IS intercellular space, V vacuole. Scale bars 100 nm (a, c, d), 200 nm (b)

Mentions: LTP1 epitopes were present in callus cell walls, in which the labelling was uniformly distributed throughout the wall (Fig. 8a). The labelling was also observed on the edges of cell walls lining the intercellular spaces as well as within the spaces (Fig. 8b). Apart from the cell wall localization of labelling, analysis of protodermal explant cells at the ultrastructural level revealed the presence of LTP1 epitopes within the cytoplasm, in close proximity to membranes of the endoplasmic reticulum (ER, Figs. 6c, 8c), as well as within secretory vesicles located close to the cell wall and in the vicinity of formed intercellular spaces (not shown). Moreover, the LTP1 epitopes were rarely present in the vacuoles (Fig. 8c) and plastids (not shown). No accumulation of the gold particles was seen in control sections incubated with the blocking buffer instead of the primary antibody (Figs. 6f, 7e, 8d).Fig. 8


Distribution of lipid transfer protein 1 (LTP1) epitopes associated with morphogenic events during somatic embryogenesis of Arabidopsis thaliana.

Potocka I, Baldwin TC, Kurczynska EU - Plant Cell Rep. (2012)

Immunogold localization of LTP1 epitopes in the cell walls and cytoplasm of the explants. a Callus cell from an explant cultured for 21 days, notice densely and uniformly labelled cell wall, the asterisk marks the cell interior. b Tricellular junction with intercellular space formed between the adaxial protodermal and subprotodermal cells of the cotyledon, day 4 of culture. c Intracellular localization of LTP1 epitopes, adaxial protodermal cell of the cotyledon, day 7 of culture. d Negative control, no labelling visible. CW cell wall, ER endoplasmic reticulum, IS intercellular space, V vacuole. Scale bars 100 nm (a, c, d), 200 nm (b)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3472069&req=5

Fig8: Immunogold localization of LTP1 epitopes in the cell walls and cytoplasm of the explants. a Callus cell from an explant cultured for 21 days, notice densely and uniformly labelled cell wall, the asterisk marks the cell interior. b Tricellular junction with intercellular space formed between the adaxial protodermal and subprotodermal cells of the cotyledon, day 4 of culture. c Intracellular localization of LTP1 epitopes, adaxial protodermal cell of the cotyledon, day 7 of culture. d Negative control, no labelling visible. CW cell wall, ER endoplasmic reticulum, IS intercellular space, V vacuole. Scale bars 100 nm (a, c, d), 200 nm (b)
Mentions: LTP1 epitopes were present in callus cell walls, in which the labelling was uniformly distributed throughout the wall (Fig. 8a). The labelling was also observed on the edges of cell walls lining the intercellular spaces as well as within the spaces (Fig. 8b). Apart from the cell wall localization of labelling, analysis of protodermal explant cells at the ultrastructural level revealed the presence of LTP1 epitopes within the cytoplasm, in close proximity to membranes of the endoplasmic reticulum (ER, Figs. 6c, 8c), as well as within secretory vesicles located close to the cell wall and in the vicinity of formed intercellular spaces (not shown). Moreover, the LTP1 epitopes were rarely present in the vacuoles (Fig. 8c) and plastids (not shown). No accumulation of the gold particles was seen in control sections incubated with the blocking buffer instead of the primary antibody (Figs. 6f, 7e, 8d).Fig. 8

Bottom Line: The labelling was strongest in both the outer periclinal and anticlinal walls of the adaxial, protodermal cells of the proximal region of the cotyledon.The putative role(s) of lipid transfer proteins in the formation of lipid lamellae and in cell differentiation are discussed.Key message Occurrence of lipid transfer protein 1 epitopes in Arabidopsis explant cells accompanies changes in cell fate and may be correlated with the deposition of lipid substances in the cell walls.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Cell Biology, University of Silesia, Jagiellońska 28, 40-032, Katowice, Poland. izabela.potocka@us.edu.pl

ABSTRACT
Using immunocytochemical methods, at both the light and electron microscopic level, we have investigated the spatial and temporal distribution of lipid transfer protein 1 (LTP1) epitopes during the induction of somatic embryogenesis in explants of Arabidopsis thaliana. Immunofluorescence labelling demonstrated the presence of high levels of LTP1 epitopes within the proximal regions of the cotyledons (embryogenic regions) associated with particular morphogenetic events, including intense cell division activity, cotyledon swelling, cell loosening and callus formation. Precise analysis of the signal localization in protodermal and subprotodermal cells indicated that cells exhibiting features typical of embryogenic cells were strongly labelled, both in walls and the cytoplasm, while in the majority of meristematic-like cells no signal was observed. Staining with lipophilic dyes revealed a correlation between the distribution of LTP1 epitopes and lipid substances within the cell wall. Differences in label abundance and distribution between embryogenic and non-embryogenic regions of explants were studied in detail with the use of immunogold electron microscopy. The labelling was strongest in both the outer periclinal and anticlinal walls of the adaxial, protodermal cells of the proximal region of the cotyledon. The putative role(s) of lipid transfer proteins in the formation of lipid lamellae and in cell differentiation are discussed. Key message Occurrence of lipid transfer protein 1 epitopes in Arabidopsis explant cells accompanies changes in cell fate and may be correlated with the deposition of lipid substances in the cell walls.

Show MeSH
Related in: MedlinePlus