植物學(xué)

來源出版物：Journal of Integrative Plant Biology，2014，57（4）: 349-356聯(lián)系郵箱：Yuji Tsutsumi，y-tsutsu@agr.kyushu-u.ac.jp

封面介紹：The cover shows a confocal microscope image of tobacco protoplasts transiently transformed with a gene cassette containing a signal sequence of a lignin polymerising peroxidase of Norway spruce fused with a GFP sequence，showing the ER- and apoplast-localized lignin polymerising peroxidase（green）that is involved in cell wall formation（see also Shigeto et al.，pp. 349-356）. Chloroplast auto-fluorescence is shown in red. Photo was taken by Mikko Lehtonen，University of Helsinki.

Simultaneously disrupting AtPrx2，AtPrx25 and AtPrx71 alters lignin content and structure in Arabidopsis stem

Jun Shigeto，Yoshitaka Itoh，Sakie Hirao，et al.

Plant class III heme peroxidases catalyze lignin polymerization. Previous reports have shown that at least three Arabidopsis thaliana peroxidases，AtPrx2，AtPrx25 and AtPrx71，are involved in stem lignification using T-DNA insertion mutants，atprx2，atprx25，and atprx71. Here，we generated three double mutants，atprx2/atprx25，atprx2/atprx71，and atprx25/atprx71，and investigated the impact of the simultaneous deficiency of these peroxidases on lignins and plant growth. Stem tissue analysis using the acetyl bromide method and derivatization followed by reductive cleavage revealed improved lignin characteristics，such as lowered lignin content and increased arylglycerol-β-aryl（β-O-4）linkage type，especially β-O-4 linked syringyl units，in lignin，supporting the roles of these genes in lignin polymerization. In addition，none of the double mutants exhibited severe growth defects，such as shorter plant stature，dwarfing，or sterility，and their stems had improved cell wall degradability. This study will contribute to progress in lignin bioengineering to improve lignocellulosic biomass.

Arabidopsis； knockout mutant； lignin biosynthesis； plant peroxidase