Transient expression of green fluorescent protein in parasitic dodder as a tool for studying of cytoskeleton

Abstract

Dodder (Cuscuta) species cause severe agricultural damage in many countries throughout the world. To establish strategies for control of its growth and spreading it is important to study its life cycle and survival strategies. For these efforts genetic modification would represent a powerful tool. Here we report on Agrobacteriummediated transformation of dodder using green fluorescent protein (GFP) fused to actin-binding protein as a vital marker. Since the shoot of germinating C. europaea contains a functional apical meristem and grows quickly comparing to the root-like structure, the shoot apex was used here as explant. The transgene expression was only transient, nevertheless it enabled to detect allocation of actin filaments and studying the cytoskeleton organization in dodder shoot apex. Transient expression of GFP appears to be a suitable method for studying Cuscuta development through cytoskeleton organisation that is presently largely unexplored.

Cytoskeleton in the Parasitic Plant Cuscuta During Germination and Prehaustorium Formation

“…It was found previously that the contractile actin bundles with the phosphorylated myosin form a highly ordered, dynamic, and scaffolding perinuclear structure in various eukaryotic cells ( Khatau et al, 2009 ). Shoot apex contains many dividing cells in contrast to root-like structure, where mitoses seem to be absent ( Kaštier et al, 2017 ). These results are consistent with the findings of Sherman et al (2008) that α- and β-tubulins were easily detectable in extracts of C. pentagona shoot tissues.…”

“…Our results confirm the key role of cortical microtubules in xylem vessel differentiation in dodder shoots. Besides the supply and redistribution of water and nutrients throughout the rapidly elongating dodder seedling, xylem differentiation is also required for the formation of the functional connection between the parasite and the host plant necessary for the completion of life cycle of these parasitic plants after root-like structure degradation ( Kaštier et al, 2017 ; Svubova et al, 2017 ). It has been found before that the differentiation of tracheal elements in C. japonica root-like structures differs from that in shoots ( Lee et al, 2000 ).…”

“…Most dodders form only rudimentary roots (root-like structures) with root apices surrounded by a circle of trichomes resembling root hairs. They become senescent by the 7th–10th day and collapse completely by the 14th–20th day post-germination, transferring the baton of growth to haustorium in a sort of developmental treadmilling essential for dodder survival ( Lyshede, 1985 , 1986 ; Sherman et al, 2008 ; Kaštier et al, 2017 ). Dodder shoots have mitotically active cells in the apex and lack mechanical tissues ( Toma et al, 2005 ; Sherman et al, 2008 ).…”