tailieunhanh - Báo cáo khoa học: Gene expression in response to endoplasmic reticulum stress in Arabidopsis thaliana

Eukaryotic cells respond to the accumulation of unfolded proteins in the endoplasmic reticulum (ER). In this case, so-called unfolded protein response (UPR) genes are induced. We determined the transcriptional expression ofArabidopsis thaliana UPRgenes by fluid microarray analysis of tunicamycin-treated plantlets. Two hundred and fifteen up-regulated genes and 17 down-regulated ones were identified. | ềFEBS Journal Gene expression in response to endoplasmic reticulum stress in Arabidopsis thaliana Shinya Kamauchi Hiromi Nakatani Chiharu Nakano and Reiko Urade Graduate Schoolof Agriculture Kyoto University Uji Japan Keywords endoplasmic reticulum fluid microarray gene expression tunicamycin unfolded protein response Correspondence R. Urade Graduate Schoolof Agriculture Kyoto University Uji Kyoto 611-0011 Japan Fax 81 774 38 3758 Tel 81 774 38 3757 E-mail urade@ Database The nucleotide sequence data for soybean SEL-1L are available in the DDBJ EMBL GenBank databases under accession number AB197676. Received 15 March 2005 revised 11 May 2005 accepted 16 May 2005 doi Eukaryotic cells respond to the accumulation of unfolded proteins in the endoplasmic reticulum ER . In this case so-called unfolded protein response UPR genes are induced. We determined the transcriptional expression of Arabidopsis thaliana UPR genes by fluid microarray analysis of tunicamycin-treated plantlets. Two hundred and fifteen up-regulated genes and 17 down-regulated ones were identified. These genes were reanalyzed with functional DNA microarrays using DNA fragments cloned through fluid microarray analysis. Finally 36 up-regulated and two down-regulated genes were recognized as UPR genes. Among them the up-regulation of genes related to protein degradation HRD1 SEL-1L HRD3 and DER1 regulation of translation P58ipk and apoptosis BAX inhibitor-1 was reconfirmed by real-time reverse transcriptase-PCR. The induction of SEL-1L protein in an Arabidopsis membrane fraction on tunicamycin-treat-ment was demonstrated. Phosphorylation of initiation factor-2a which was inhibited by P58IPK was decreased in tunicamycin-treated plantlets. However regulatory changes in translation caused by ER stress were not detected in Arabidopsis. Plant cells appeared to have a strategy for overcoming ER stress through enhancement of protein folding activity degradation of