JXB Advance Access published online on November 3, 2009
Journal of Experimental Botany, doi:10.1093/jxb/erp292
REVIEW-ARTICLE |
The AMI1 gene family: indole-3-acetamide hydrolase functions in auxin biosynthesis in plants
1Graduate School of Bioscience, Tokai University, 317 Nishino, Numazu, Shizuoka 410-0321, Japan
2RIKEN Plant Science Center, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
3Plant Biotechnology Division, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
* To whom correspondence should be addressed: E-mail: y-mano{at}wing.ncc.u-tokai.ac.jp
Novel genes that function in the conversion of indole-3-acetamide (IAM) into indole-3-acetic acid (IAA), which were previously thought to exist only in the bacterial genome, have been isolated from plants. The finding of the AtAMI1 gene in Arabidopsis thaliana and the NtAMI1 gene in Nicotiana tabacum, which encode indole-3-acetamide hydrolase, indicates the existence of a new pathway for auxin biosynthesis in plants. This review summarizes the characteristics of these genes involved in auxin biosynthesis and discusses the possibility of the AMI1 gene family being widely distributed in the plant kingdom. Its evolutionary relationship to bacterial indole-3-acetamide hydrolase, based on phylogenetic analyses, is also discussed.
Key words: AMI1 gene family, amidase motif, AtAMI1, auxin biosynthesis, bioinformatics, indole-3-acetamide hydrolase, NtAMI1, phylogenetic analysis, Ri plasmid, Toc64
Received 23 June 2009; Revised 9 September 2009 Accepted 9 September 2009