caa a22 4500 445840080 CHVBK 20180317145341.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s00709-010-0208-7 doi (NATIONALLICENCE)springer-10.1007/s00709-010-0208-7 Do symplasmic networks in cambial zones correspond with secondary growth patterns? [Elektronische Daten] [Maike Fuchs, Aart van Bel, Katrin Ehlers] The plasmodesmal (PD) network in the cambial zone of Arabidopsis thaliana hypocotyls was analysed using electron microscopy and dye-coupling studies and compared to those of internodes of Populus nigra and Solanum lycopersicum. In all species, PD densities and frequencies undergo alterations in topologically successive cambial walls reflecting species-specific patterns of PD degradation and PD insertion during cell development. Longitudinal PD fission is responsible for an abrupt increment of PD numbers in specific walls of the youngest derivatives at the xylem and/or phloem side. Here, PDs seem to mediate positional signalling to control tissue fate and early cell determination. PD numbers at all cambial interfaces of A. thaliana correspond to those of the herbaceous tomato, but are higher with the woody poplar. This suggests a positive correlation between PD frequencies and the rapidity of cell division activity. Photoactivated green fluorescent protein (26kDa) did not diffuse through cambial PDs of A. thaliana. This is in keeping with the common size exclusion limit (SEL) of 8-10kDa observed for PDs at the youngest interfaces of tomato and poplar which may mediate diffusive exchange of developmental signals of equal molecular size. The regular growth patterns in internodal cambial zones of poplar and tomato result from synchronized cell division activity of neighbouring initials. A. thaliana hypocotyls have an irregular mode of secondary growth. Here, signalling through PDs in misaligned radial walls between non-homologous derivatives may control tissue development. The observed organizational differences between the cambia cast doubts on the suitability of A. thaliana as a model plant for cambial research. Springer-Verlag, 2010 Cambial zone nationallicence Determination nationallicence Differentiation nationallicence Growth patterns nationallicence Plasmodesmata nationallicence Plasmodesmal fission nationallicence Positional signalling nationallicence Fuchs Maike Institute of General Botany, Justus-Liebig-University, Senckenbergstrasse 17, 35390, Giessen, Germany aut van Bel Aart Institute of General Botany, Justus-Liebig-University, Senckenbergstrasse 17, 35390, Giessen, Germany aut Ehlers Katrin Institute of General Botany, Justus-Liebig-University, Senckenbergstrasse 17, 35390, Giessen, Germany aut Protoplasma Springer Vienna 248/1(2011-01-01), 141-151 0033-183X 248:1<141 2011 248 709 https://doi.org/10.1007/s00709-010-0208-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00709-010-0208-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Fuchs Maike Institute of General Botany, Justus-Liebig-University, Senckenbergstrasse 17, 35390, Giessen, Germany aut NATIONALLICENCE 700 1- van Bel Aart Institute of General Botany, Justus-Liebig-University, Senckenbergstrasse 17, 35390, Giessen, Germany aut NATIONALLICENCE 700 1- Ehlers Katrin Institute of General Botany, Justus-Liebig-University, Senckenbergstrasse 17, 35390, Giessen, Germany aut NATIONALLICENCE 773 0- Protoplasma Springer Vienna 248/1(2011-01-01), 141-151 0033-183X 248:1<141 2011 248 709 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer