Complete substitution of a secondary cell wall with primary cell wall in Arabidopsis (Nature Plants – $)

Plant cell walls are important for terrestrial lifestyle, providing support and directing the plant growth. The primary and secondary cell walls differ in their chemical composition and flexibility. Secondary cell walls are less perceptive to industrial degradation processes and therefore pose problems in turning the plant biomass into simpler sugars. To identify new regulatory components of cell wall synthesis Sakamoto et al. screened nts1/nts3 mutants, lacking secondary cell walls in the interfascicular fibre cells, complemented with selected 300 transcription factors under the NTS3 promoter. The nts1/nts3 phenotype was complemented with ERF035 construct, resulting in the thicker cell walls without lignin, which is characteristic to the secondary cell walls. ERF035 was observed to regulate the transcription of primary cell wall biosynthesis genes and was directly interacting with the promoter elements of Cellulose Synthase (CESA1). Although the composition of thickened walls in ERF035 lines resembled primary cell walls, the higher degree of cellulose crystallization and polymerization was observed. (Summary by Magdalena Julkowska) Nature Plants 10.1038/s41477-018-0160-4