TY - JOUR
T1 - Functional and structural analysis of genes encoding oxidosqualene cyclases of Lotus japonicus
AU - Sawai, Satoru
AU - Shindo, Tamotsu
AU - Sato, Shusei
AU - Kaneko, Takakazu
AU - Tabata, Satoshi
AU - Ayabe, Shin Ichi
AU - Aoki, Toshio
N1 - Funding Information:
The authors are grateful to Prof. Yutaka Ebizuka (Graduate School of Pharmaceutical Sciences, The University of Tokyo) for yeast GIL77 strain, and Dr. Norimoto Shimada (Department of Applied Biological Sciences, Nihon University) for the cDNA samples of L. japonicus. The authors thank Emi Suzuki (The General Research Institute of Nihon University) for EI-MS analyses. This work was supported by the Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research (C) No. 14540603), the Ministry of Education, Culture, Sports, Science and Technology of Japan (Grant-in-Aid for COE Research) and the New Energy and Industrial Technology Development Organization.
PY - 2006/2
Y1 - 2006/2
N2 - The structures of cyclic triterpenoids of higher plants, whose skeletons are constructed by oxidosqualene cyclases (OSCs), are remarkably diverse in contrast to the limited variation in sterol/triterpenoid structures of other organisms. We comprehensively analyzed the functions and structures of OSC genes of a model legume, Lotus japonicus, and compared them with those of Arabidopsis thaliana in order to elucidate the diversification process of plant cyclic triterpenoids. Eight OSC genes (OSC1-OSC8) formed two sets of clusters in chromosomes 2 and 3 of L. japonicus. OSC1 and OSC8 corresponded to the previously reported LjAMY1 and LjAMY2, respectively [I. Iturbe-Ormaetxe, K. Haralampidis, K. Papadopoulou, A.E. Osbourn, Molecular cloning and characterization of triterpene synthases from Medicago truncatula and Lotus japonicus, Plant Mol. Biol. 51 (2003) 731-743]. OSC1 (the full-length version of LjAMY1), OSC3 and OSC5 were identified as β-amyrin synthase, lupeol synthase and cycloartenol synthase, respectively, by heterologous expression of the cDNAs in an OSC-disrupted yeast mutant. A phylogenetic tree based on deduced amino acid sequences categorized eudicot OSCs into four groups and suggested an extensive diversification of the group IV OSCs.
AB - The structures of cyclic triterpenoids of higher plants, whose skeletons are constructed by oxidosqualene cyclases (OSCs), are remarkably diverse in contrast to the limited variation in sterol/triterpenoid structures of other organisms. We comprehensively analyzed the functions and structures of OSC genes of a model legume, Lotus japonicus, and compared them with those of Arabidopsis thaliana in order to elucidate the diversification process of plant cyclic triterpenoids. Eight OSC genes (OSC1-OSC8) formed two sets of clusters in chromosomes 2 and 3 of L. japonicus. OSC1 and OSC8 corresponded to the previously reported LjAMY1 and LjAMY2, respectively [I. Iturbe-Ormaetxe, K. Haralampidis, K. Papadopoulou, A.E. Osbourn, Molecular cloning and characterization of triterpene synthases from Medicago truncatula and Lotus japonicus, Plant Mol. Biol. 51 (2003) 731-743]. OSC1 (the full-length version of LjAMY1), OSC3 and OSC5 were identified as β-amyrin synthase, lupeol synthase and cycloartenol synthase, respectively, by heterologous expression of the cDNAs in an OSC-disrupted yeast mutant. A phylogenetic tree based on deduced amino acid sequences categorized eudicot OSCs into four groups and suggested an extensive diversification of the group IV OSCs.
KW - Exon length
KW - Gene structure
KW - Lotus japonicus
KW - Oxidosqualene cyclase
KW - Triterpenoid
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U2 - 10.1016/j.plantsci.2005.08.027
DO - 10.1016/j.plantsci.2005.08.027
M3 - Article
AN - SCOPUS:29244486464
VL - 170
SP - 247
EP - 257
JO - Plant Science
JF - Plant Science
SN - 0168-9452
IS - 2
ER -