Schwarzerová K., Vondráková Z., Fischer L., Boříková P., Bellinvia E., Eliášová K., Havelková L., Fišerová J., Vágner M., Opatrný Z.
BMC PLANT BIOLOGY
10::
89,,
2010
Keywords:
somatic embryogenesis, Norway spruce, actin,
Abstract:
Background: Somatic embryogenesis in spruce is a process of high importance for biotechnology,
yet it comprises of orchestrated series of events whose cellular and molecular details
are not well understood. In this study, we examined the role of actin cytoskeleton
during somatic embryogenesis in Norway spruce line AFO 541 by means of anti-actin
drugs.
Results: Application of low doses (50-100 nM) of latrunculin B (Lat B) during the maturation
of somatic embryos predominantly killed suspensor cells while leaving the cells in
meristematic centres alive, indicating differential sensitivity of actin in the two cell
types. The treatment resulted in faster development of more advanced embryos into
mature somatic embryos and elimination of insufficiently developed ones. In
searching for the cause of the differential actin sensitivity of the two cell types, we
analysed the composition of actin isoforms in the culture and isolated four spruce
actin genes. Analysis of their expression during embryo maturation revealed that one
actin isoform was expressed constitutively in both cell types, whereas three actin
isoforms were expressed predominantly in suspensor cells and their expression
declined during the maturation. The expression decline was greatly enhanced by Lat
B treatment. Sequence analysis revealed amino-acid substitutions in the Lat B-binding
site in one of the suspensor-specific actin isoforms, which may result in a different
binding affinity for Lat B.
Conclusions: We show that manipulating actin in specific cell types in somatic embryos using Lat
B treatment accelerated and even synchronized the development of somatic embryos
and may be of practical use in biotechnology.
IEB authors: Kateřina Eliášová,
Martin Vágner,
Zuzana Vondráková
Čeština
English