Research & Faculty

Default Header Image

KORRIGAN1 and its Aspen Homolog PttCel9A1 Decrease Cellulose Crystallinity in Arabidopsis Stems

TitleKORRIGAN1 and its Aspen Homolog PttCel9A1 Decrease Cellulose Crystallinity in Arabidopsis Stems
Publication TypeJournal Article
Year of Publication2009
AuthorsTakahashi, J, Rudsander, UJ, Hedenstrom, M, Banasiak, A, Harholt, J, Amelot, N, Immerzeel, P, Ryden, P, Endo, S, Ibatullin, FM, Brumer, H, del Campillo, E, Master, ER, Scheller, HVibe, Sundberg, B, Teeri, TT, Mellerowicz, EJ
JournalPLANT AND CELL PHYSIOLOGY
Volume50
Pagination1099-1115
Date PublishedJUN
Type of ArticleArticle
ISSN0032-0781
Abstract

KORRIGAN1 (KOR1) is a membrane-bound cellulase implicated in cellulose biosynthesis. PttCel9A1 from hybrid aspen (Populus tremula L. tremuloides Michx.) has high sequence similarity to KOR1 and we demonstrate here that it complements kor1-1 mutants, indicating that it is a KOR1 ortholog. We investigated the function of PttCel9A1/KOR1 in Arabidopsis secondary growth using transgenic lines expressing 35S::PttCel9A1 and the KOR1 mutant line irx2-2. The presence of elevated levels of PttCel9A1/KOR1 in secondary walls of 35S::PttCel9A1 lines was confirmed by in muro visualization of cellulase activity. Compared with the wild type, 35S::PttCel9A1 lines had higher trifluoroacetic acid (TFA)-hydrolyzable glucan contents, similar Updegraff cellulose contents and lower cellulose crystallinity indices, as determined by (13)C solid-state nuclear magnetic resonance (NMR) spectroscopy. irx2-2 mutants had wild-type TFA-hydrolyzable glucan contents, but reduced Updegraff cellulose contents and higher than wild-type cellulose crystallinity indices. The data support the hypothesis that PttCel9A1/KOR1 activity is present in cell walls, where it facilitates cellulose biosynthesis in a way that increases the amount of non-crystalline cellulose.

DOI10.1093/pcp/pcp062