Neighboring parenchyma cells contribute to Arabidopsis xylem lignification, while lignification of interfascicular fibers is cell autonomous.

Defining the Diverse Cell Populations Contributing to Lignification in Arabidopsis Stems.

Many land plants evolved tall and sturdy growth habits due to specialized cells with thick lignified cell walls: tracheary elements that function in water transport and fibers that function in structural support. The objective of this study was to define how and when diverse cell populations contribute lignin precursors, monolignols, to secondary cell walls during lignification of the Arabidops...

Good neighbor hypothesis of lignification holds for xylem cells, but not for interfascicular fibers.

Non-cell-autonomous postmortem lignification of tracheary elements in Zinnia elegans.

Postmortem lignification of xylem tracheary elements (TEs) has been debated for decades. Here, we provide evidence in Zinnia elegans TE cell cultures, using pharmacological inhibitors and in intact Z. elegans plants using Fourier transform infrared microspectroscopy, that TE lignification occurs postmortem (i.e., after TE programmed cell death). In situ RT-PCR verified expression of the lignin ...

Disruption of LACCASE4 and 17 results in tissue-specific alterations to lignification of Arabidopsis thaliana stems.

Peroxidases have been shown to be involved in the polymerization of lignin precursors, but it remains unclear whether laccases (EC 1.10.3.2) participate in constitutive lignification. We addressed this issue by studying laccase T-DNA insertion mutants in Arabidopsis thaliana. We identified two genes, LAC4 and LAC17, which are strongly expressed in stems. LAC17 was mainly expressed in the interf...

Erratum: Identification of novel transcription factors regulating secondary cell wall formation in Arabidopsis

The presence of lignin in secondary cell walls (SCW) is a major factor preventing hydrolytic enzymes from gaining access to cellulose, thereby limiting the saccharification potential of plant biomass. To understand how lignification is regulated is a prerequisite for selecting plant biomass better adapted to bioethanol production. Because transcriptional regulation is a major mechanism controll...