Plant and Cell Physiology Advance Access originally published online on March 22, 2007
Plant and Cell Physiology 2007 48(5):700-714; doi:10.1093/pcp/pcm038
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Induction of a Novel XIP-Type Xylanase Inhibitor by External Ascorbic Acid Treatment and Differential Expression of XIP-Family Genes in Rice
Graduate School of Biosphere Sciences, Hiroshima University, Kagamiyama, Higashi-Hiroshima, 739-8528 Japan
*Corresponding author: E-mail, mesaka{at}hiroshima-u.ac.jp; Fax, +81-824-24-7927.
 |
Abstract |
|---|
Rice microarray analysis showed that a number of stress-related genes are induced by external addition of L-ascorbic acid (AsA). The gene designated as AK073843 which is homologous to class 
chitinase was found to exhibit the highest induction among these genes. However, its crucial residues within the chitinase active site are substituted with other residues, suggesting that the protein has no chitinase activity. The recombinant protein which is encoded by the AK073843 gene produced in Escherichia coli has xylanase inhibitor activity, indicating that the gene encodes a novel rice XIP-type xylanase inhibitor protein (OsXIP). The expression of OsXIP was enhanced not only by exogenous AsA treatment but also by various stresses such as citrate and sodium chloride treatments, and wounding; however, it was not influenced by increasing endogenous AsA content. External AsA treatment caused a significant increase in electrolyte leakage from rice root. These results suggested that OsXIP was induced by stress which is caused by external AsA treatment. Rice XIP-family genes, OsXIP, riceXIP and RIXI, showed differential organ-specific expression. Also, these genes were differentially induced by stress and stress-related phytohormones. The transcripts of OsXIP and riceXIP were undetectable under normal conditions, and were drastically induced by wounding and methyl jasmonate (MeJA) treatment in the root. RIXI was constitutively expressed in the shoot but not induced by wounding and stress-related phytohormones. Thus, XIP-type xylanase inhibitors were suggested to be specialized in their function and involved in defense mechanisms in rice.
Keywords: Ascorbic acid - DNA microarray - Oryza sativa - Stress response - Xylanase inhibitor
Abbreviations: AsA, ascorbic acid; DHA, dehydroascorbate; DIG, digoxigenin; GH, glycoside hydrolase family; GSH, reduced glutathione; L-Gal, L-galactono-1,4-lactone; IPTG, isopropyl-ß-D-thiogalactopyranoside; MeJA, methyl jasmonate; SA, salicylic acid; TAXI, Triticum aestivum xylanase inhibitor; TBARS, thiobarbituric acid-reactive substances; XIP, xylanase inhibitor protein.
(Received February 8, 2006; Accepted March 19, 2007)
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  X. Huang, G. Lu, Q. Zhao, X. Liu, and B. Han Genome-Wide Analysis of Transposon Insertion Polymorphisms Reveals Intraspecific Variation in Cultivated Rice Plant Physiology, September 1, 2008; 148(1): 25 - 40. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Tokunaga, Y. Miyata, Y. Fujikawa, and M. Esaka RNAi-Mediated Knockdown of the XIP-Type Endoxylanase Inhibitor Gene, OsXIP, Has No Effect on Grain Development and Germination in Rice Plant Cell Physiol., July 1, 2008; 49(7): 1122 - 1127. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. A. Badejo, N. Tanaka, and M. Esaka Analysis of GDP-D-Mannose Pyrophosphorylase Gene Promoter from Acerola (Malpighia glabra) and Increase in Ascorbate Content of Transgenic Tobacco Expressing the Acerola Gene Plant Cell Physiol., January 1, 2008; 49(1): 126 - 132. [Abstract] [Full Text] [PDF]
|
|