Cytoskeletal organization during xylem cell differentiation

Abstract

The water and mineral conductive tube, the xylem vessel and tracheid, is a highly conspicuous tissue due to its elaborately patterned secondary-wall deposition. One constituent of the xylem vessel and tracheid, the tracheary element, is an empty dead cell that develops secondary walls in the elaborate patterns. The wall pattern is appropriately regulated according to the developmental stage of the plant. The cytoskeleton is an essential component of this regulation. In fact, the cortical microtubule is well known to participate in patterned secondary cell wall formation. The dynamic rearrangement of the microtubules and actin filaments have also been recognized in the cultured cells differentiating into tracheary elements in vitro. There has recently been considerable progress in our understanding of the dynamics and regulation of cortical microtubules, and several plant microtubule associated proteins have been identified and characterized. The microtubules have been observed during tracheary element differentiation in living Arabidopsis thaliana cells. Based on this recently acquired information on the plant cytoskeleton and tracheary element differentiation, this review discusses the role of the cytoskeleton in secondary cell wall formation.

Biotechnological aspects of cytoskeletal regulation in plants

“…Well established in vitro systems are suspension cultures of Zinnia elegans mesophyll cells that under appropriate xylogenic conditions undergo terminal differentiation to tracheary elements (reviewed in Fukuda et al, 1994). Such differentiating tracheary element cultures provided an experimental platform which allowed the elucidation of transcriptomic changes accompanying wood formation (Demura and Fukuda, 2007) but most importantly highlighted the central role of the cytoskeleton in secondary wall patterning (Oda and Hasezawa, 2006).…”

Organisation and regulation of the cytoskeleton in plant programmed cell death

“…When deposition is complete, the contents of the cell are dismantled by PCD. 7,8 In the case of Zinnia model system, before tracheary elements differentiate, cortical microtubules are oriented transversely and spaced randomly. 9 Upon differentiation, microtubules form thick bundles between cytoplasmic domains containing virtually no microtubules (Table 1).…”

Rho of Plant GTPase Signaling Regulates the Behavior of Arabidopsis Kinesin-13A to Establish Secondary Cell Wall Patterns

“…Secondary cell wall pits, areas where the secondary cell wall is not deposited, provide a lateral pathway for transporting xylem sap. Cortical microtubules play a central role in secondary cell wall deposition; during xylem vessel differentiation, cortical microtubules are bundled and disassembled at multiple domains to establish the distinct secondary cell wall pattern (Oda et al, 2005(Oda et al, , 2010Oda and Hasezawa, 2006). Although several microtubule-associated proteins (MAPs), including MAP65 (Mao et al, 2006) and MAP70 (Pesquet et al, 2010), regulate the organization of cortical microtubules during xylem differentiation (Oda and Fukuda, 2012b), the overall mechanism underlying the spatial determination of secondary wall deposition in xylem cells has not yet been clarified.…”