Cell-type specific lignification in plant vasculature

Lignin is a complex phenolic polymer which provides rigidity and hydrophobicity to the vascular xylem tissues of plants, but it also entails recalcitrance of the lignocellulosic material in bioprocessing.

In the secondary xylem tissues of the stem, lignin is present in the walls of most cell types but lignin composition varies between the different cell types. The mechanisms underlying the cell-type specific lignification of the vascular tissues has until now been unknown.

We have recently identified a PIRIN2 (PRN2) protein as the first known factor controlling lignin composition of vascular tissues in a cell-type specific manner in Arabidopsis thaliana.

In this project, I aim to identify the molecular mechanism of PRN2 function by cell-type specific modification of lignin biosynthesis in vascular tissues of Arabidopsis thaliana and transcriptomic and phenolic profiling of specific vascular cell types.

I will also identify conservation and functional significance of cell-type specific lignification, and elucidate whether the cell-specific lignification can be utilised to improve bioprocessing properties of the lignocellulosic raw material in Populus trees.

The results are expected to identify processes and proteins that are unique to lignification of different vascular cell types, which will be beneficial for not only the basic understanding of vascular functioning in plants but also for creating tools, such as cell specific markers/promoters, for biotechnological approaches.