@article{suzuki_sakakibara_li_umezawa_chiang_2010, title={Profiling of phenylpropanoid monomers in developing xylem tissue of transgenic aspen (Populus tremuloides)}, volume={56}, ISSN={["1435-0211"]}, DOI={10.1007/s10086-009-1059-8}, abstractNote={Here we describe alterations in the cinnamate/monolignol pathway in three transgenic aspen lines: one with downregulated expression of 4-coumarate:CoA ligase (4CL), one with upregulated expression of coniferaldehyde 5-hydroxylase (CAld5H), and a 4CL downregulated/CAld5H upregulated line. Compared with the wild type, the 4CL downregulated line showed significantly increased levels of p-hydroxycinnamic acids such as p-coumaric, ferulic, and sinapic acids. In contrast, the CAld5H upregulated line had increased content of p-coumaryl and 5-hydroxyconiferyl alcohols. In the 4CL downregulated line, it was likely that most hydroxycinnamic acids were glycosylated. These results strongly suggest that the downregulation of 4CL and upregulation of CAld5H disrupt the metabolic flow through the cinnamate/monolignol pathway and thus alter the amount and structure of its final product, lignin.}, number={1}, journal={JOURNAL OF WOOD SCIENCE}, author={Suzuki, Shiro and Sakakibara, Norikazu and Li, Laigeng and Umezawa, Toshiaki and Chiang, Vincent L.}, year={2010}, month={Feb}, pages={71–76} } @article{nakatsubo_li_hattori_lu_sakakibara_chiang_shimada_suzuki_umezawa_2008, title={Roles of 5-hydroxyconiferylaldehyde and caffeoyl CoA O-methyltransferases in monolignol biosynthesis in Carthamus tinctorius}, volume={41}, number={9-10}, journal={Cellulose Chemistry and Technology}, author={Nakatsubo, T. and Li, L. and Hattori, T. and Lu, S. and Sakakibara, N. and Chiang, V. L. and Shimada, M. and Suzuki, S. and Umezawa, T.}, year={2008}, pages={511–520} } @article{suzuki_li_sun_chiang_2006, title={The cellulose synthase gene superfamily and biochemical functions of xylem-specific cellulose synthase-like genes in Populus trichocarpa}, volume={142}, ISSN={["1532-2548"]}, DOI={10.1104/pp.106.086678}, abstractNote={AbstractWood from forest trees modified for more cellulose or hemicelluloses could be a major feedstock for fuel ethanol. Xylan and glucomannan are the two major hemicelluloses in wood of angiosperms. However, little is known about the genes and gene products involved in the synthesis of these wood polysaccharides. Using Populus trichocarpa as a model angiosperm tree, we report here a systematic analysis in various tissues of the absolute transcript copy numbers of cellulose synthase superfamily genes, the cellulose synthase (CesA) and the hemicellulose-related cellulose synthase-like (Csl) genes. Candidate Csl genes were characterized for biochemical functions in Drosophila Schneider 2 (S2) cells. Of the 48 identified members, 37 were found expressed in various tissues. Seven CesA genes are xylem specific, suggesting gene networks for the synthesis of wood cellulose. Four Csl genes are xylem specific, three of which belong to the CslA subfamily. The more xylem-specific CslA subfamily is represented by three types of members: PtCslA1, PtCslA3, and PtCslA5. They share high sequence homology, but their recombinant proteins produced by the S2 cells exhibited distinct substrate specificity. PtCslA5 had no catalytic activity with the substrates for xylan or glucomannan. PtCslA1 and PtCslA3 encoded mannan synthases, but PtCslA1 further encoded a glucomannan synthase for the synthesis of (1→4)-β-d-glucomannan. The expression of PtCslA1 is most highly xylem specific, suggesting a key role for it in the synthesis of wood glucomannan. The results may help guide further studies to learn about the regulation of cellulose and hemicellulose synthesis in wood.}, number={3}, journal={PLANT PHYSIOLOGY}, author={Suzuki, Shiro and Li, Laigeng and Sun, Ying-Hsuan and Chiang, Vincent L.}, year={2006}, month={Nov}, pages={1233–1245} }