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Plant function and evolutionary biology
RESEARCH ARTICLE

Qualitative and quantitative analyses of the plasmodesmata that accompany cell fate changes during the somatic embryogenesis of Arabidopsis thaliana

Kamila Godel-Jędrychowska https://orcid.org/0000-0002-0136-2746 A * and Ewa Kurczyńska A
+ Author Affiliations
- Author Affiliations

A Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, The University of Silesia, 28 Jagiellońska Street, 40-032 Katowice, Poland.


Handling Editor: Peter Bozhkov

Functional Plant Biology 49(2) 186-200 https://doi.org/10.1071/FP21243
Submitted: 14 August 2021  Accepted: 10 November 2021   Published: 29 November 2021

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Plasmodesmata (PD) are cytoplasmic and membrane-lined microchannels that enable symplasmic communication in plants, which is involved in the regulation of cell differentiation. The presented results emphasise the qualitative and quantitative analyses of PD, which are the basis of the symplasmic communication. The cells that initiate various development programmes create symplasmic domains that are characterised by different degrees of symplasmic communication. Changes in symplasmic communication are caused by the presence or absence of PD and/or the ability of signals to move through them. In the presented studies, somatic embryogenesis was used to describe the characteristics of the PD within and between the symplasmic domains in explants of the Arabidopsis thaliana (L.) Heynh ecotype Columbia-0 and 35S:BBM transgenic line. Transmission electron microscopy was used to describe the cells that regain totipotency/pluripotency during somatic embryogenesis, as well as the number and shape of the PD in the different symplasmic domains of the explants and somatic embryos. Array tomography was used to create a 3D reconstruction of the protodermal cells of the somatic embryos with particular emphasis on the PD distribution in the cell walls. The results showed that there were different frequencies of the PD within and between the symplasmic domain that emerges during somatic embryogenesis and between the Col-0 and 35S:BBM somatic embryos with regard to the differences in the shape of the PD.

Keywords: 3D reconstruction, Arabidopsis ssp., embryogenesis, histology, morphology, plasmodesmata, transmission electron microscopy, ultrastructure.


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