Histological analysis of direct somatic embryogenesis in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> (L.) Heynh |
| |
Authors: | Ewa U Kurczyńska Ma?gorzata D Gaj Agnieszka Ujczak Ewa Mazur |
| |
Institution: | (1) Laboratory of Cell Biology, University of Silesia, ul. Jagiellońska 28, 40-032 Katowice, Poland;(2) Department of Genetics, University of Silesia, ul. Jagiellońska 28, 40-032 Katowice, Poland |
| |
Abstract: | In Arabidopsis the in vitro culture of immature zygotic embryos (IZEs) at a late stage of development, on the solid medium containing synthetic
auxin, leads to formation of somatic embryos via direct somatic embryogenesis (DSE). The presented results provide evidence
that in IZE cells competent for DSE are located in the protodermis and subprotodermis of the adaxial side of cotyledons and
somatic embryos displayed a single- or multicellular origin. Transgenic Arabidopsis lines expressing the GUS reporter gene, driven by the DR5 and LEC2 promoters, were used to analyse the distribution of auxin to mark embryogenic cells in cultured explants and develop somatic
embryos. The analysis showed that at the start of the culture auxin was accumulated in all explant tissues, but from the fourth
day onwards its location shifted to the protodermis and subprotodermis of the explant cotyledons. In globular somatic embryos
auxin was detected in all cells, with a higher concentration in the protodermis, and in the heart stage its activity was mainly
displayed in the shoot, root pole and cotyledon primordia. The embryogenic nature of dividing protodermal and subprotodermal
cells accumulating auxin was confirmed by high expression of promoter activity of LEC2 in these cells. Analysis of symplasmic tracer (CFDA) distribution indicated symplasmic isolation between tissues engaged
in DSE and other parts of an explant. Symplasmic isolation of somatic embryos from the explant was also detected. |
| |
Keywords: | Arabidopsis Auxin Direct somatic embryogenesis DR5::GUS construct LEC2 gene Symplasmic communication |
本文献已被 PubMed SpringerLink 等数据库收录! |
|