Gibberellic acid-mediated salt signaling in seed germination.
Seed germination initiates the postembryonic development of plants, which determines successful seedling establishment and plant propagation. It is therefore tightly regulated by diverse environmental conditions, including high salinity and drought, as well as by intrinsic developmental programs, among which gibberellic acid (GA) is best understood. Regulatory roles of GA in seed germination have been extensively studied. It is also known that high salinity inhibits germination by repressing genes encoding GA biosynthetic enzymes. However, it is still unclear how salt signals are coordinately incorporated into the GA signaling pathway at the molecular level. We recently demonstrated that a membrane-bound NAC transcription factor, NTL8, mediates salt signaling, primarily through a RGL2-independent GA pathway, in regulating seed germination. High salinity promotes NTL8 transcription and proteolytic activation of NTL8. Notably, the NTL8-mediated salt signaling is independent of abscisic acid (ABA). These observations indicate that membrane-mediated transcription control is an important component of salt signaling during seed germination.
Kim
Sang-Gyu
SG
Molecular Signaling Laboratory; Department of Chemistry; Seoul National University; Seoul Korea.
Park
Chung-Mo
CM
Nucleic Acids Res. 2007;35(1):203-13
17158162
Curr Biol. 2005 Nov 22;15(22):1998-2006
16303558
Curr Opin Plant Biol. 2002 Oct;5(5):376-81
12183174
Trends Plant Sci. 2003 Oct;8(10):492-7
14557046
BMC Genomics. 2006 Feb 28;7:38
16504176
Plant Cell. 2007 Mar;19(3):791-804
17384169
Plant Cell. 2004 Jun;16(6):1378-91
15161963
Plant Physiol. 2004 Sep;136(1):2782-9
15347801
Plant J. 2007 Jul;51(1):60-78
17461781
Curr Opin Plant Biol. 2002 Feb;5(1):33-6
11788305
Plant Cell. 2004 Feb;16(2):367-78
14729916
Genes Dev. 2002 Mar 1;16(5):646-58
11877383
Plant J. 2006 Nov;48(3):354-66
17010113
Science. 2006 Jan 6;311(5757):91-4
16400150
Proc Natl Acad Sci U S A. 2001 Apr 10;98(8):4782-7
11287670
Curr Opin Plant Biol. 2005 Apr;8(2):183-7
15752999
Plant Physiol Biochem. 2004 Apr;42(4):273-82
15120111
Plant Cell. 2004 Nov;16(11):3045-58
15486102