Arabidopsis thaliana 26S Proteasome Subunits RPT2a and RPT5a Are Crucial for Zinc Deficiency-Tolerance

作者：Sakamoto Takuya; Kamiya Takehiro; Sako Kaori; Yamaguchi Junji; Yamagami Mutsumi; Fujiwara Toru^*

来源：Bioscience Biotechnology and Biochemistry, 2011, 75(3): 561-567.

DOI：10.1271/bbb.100794

• Arabidopsis thaliana
• 26S proteasome
• Zn deficiency
• oxidative stress

RPTs (regulatory particle triple-A-ATPase) are components of 26S proteasome. We found novel roles of RPT2a and RPT5a in Zn deficiency-tolerance. Arabidopsis thaliana mutants carrying T-DNA in RPT2a and RPT5a were more sensitive to Zn deficiency than the wild-type. In the;pi mutants, the shoot Zn contents were similar to those Or the wild-type. Transcripts of Zn deficiency-inducible genes were highly accumulated in the rpt mutants, suggesting that the rpt mutants suffer from various Zn deficiency symptoms, although the Zn levels are not reduced. Lipid peroxidation levels, known to be increased under Zn deficiency, were higher in the rpt mutants than in the wild-type. Poly-ubiquitinated proteins were accumulated upon exposure to Zn deficiency, especially in the rpt mutants. Overall, this study indicates that RPT2a and RPT5a are involved in Zn deficiency-tolerance, possibly through alleviation of oxidative stresses and/or processing of poly-ubiquitinated proteins.

• 出版日期2011-3