フルテキストURL Plant_Cell_Physiol_58_8_1583.pdf Fig.pdf suppl_fig.pdf
著者 Cai, Qingqing| Fukushima, Hiroko| Yamamoto, Mai| Ishii, Nami| Sakamoto, Tomoaki| Kurata, Tetsuya| Motose, Hiroyasu| Takahashi, Taku|
抄録 The acaulis5 (acl5) mutant of Arabidopsis thaliana is defective in the biosynthesis of thermospermine and shows a dwarf phenotype associated with excess xylem differentiation. SAC51 was identified from a dominant suppressor of acl5, sac51-d, and encodes a basic helix-loop-helix protein. The sac51-d mutant has a premature termination codon in an upstream open reading frame (uORF) that is conserved among all four members of the SAC51 family, SAC51 and SACL1-SACL3 This suggests that thermospermine cancels the inhibitory effect of the uORF in main ORF translation. Another suppressor, sac57-d, has a mutation in the conserved uORF of SACL3 To define further the function of the SAC51 family in the thermospermine response, we analyzed T-DNA insertion mutants of each gene. Although sacl1-1 may not be a null allele, the quadruple mutant showed a semi-dwarf phenotype but with an increased level of thermospermine and decreased sensitivity to exogenous thermospermine that normally represses xylem differentiation. The sac51-1 sacl3-1 double mutant was also insensitive to thermospermine. These results suggest that SAC51 and SACL3 play a key role in thermospermine-dependent negative control of thermospermine biosynthesis and xylem differentiation. Using 5' leader-GUS (β-glucuronidase) fusion constructs, however, we detected a significant enhancement of the GUS activity by thermospermine only in SAC51 and SACL1 constructs. Furthermore, while acl5-1 sac51-1 showed the acl5 dwarf phenotype, acl5-1 sacl3-1 exhibited an extremely tiny-plant phenotype. These results suggest a complex regulatory network for the thermospermine response in which SAC51 and SACL3 function in parallel pathways.
キーワード Arabidopsis Thermospermine Translation Xylem differentiation uORF
備考 This is an Accepted Manuscript of an article published by Oxford University Press
発行日 2016-08
出版物タイトル Plant and Cell Physiology
57巻
8号
出版者 Japanese Society of Plant Physiologists
開始ページ 1583
終了ページ 1592
ISSN 0032-0781
NCID AA0077511X
資料タイプ 学術雑誌論文
言語 English
OAI-PMH Set 岡山大学
著作権者 http://creativecommons.org/licenses/by-nc-nd/4.0/
論文のバージョン author
PubMed ID 27388339
DOI 10.1093/pcp/pcw113
Web of Sience KeyUT 000384717100001
関連URL https://doi.org/10.1093/pcp/pcw113