Cytosol-localized heat shock factor-binding protein, AtHSBP, functions as a negative regulator of heat shock response by translocation to the nucleus and is required for seed development in Arabidopsis.
Heat shock response (HSR) is a universal mechanism in all organisms. It is under tight regulation by heat shock factors (HSFs) and heat shock proteins (HSPs) after heat shock (HS) to prevent stress damage. On the attenuation of HSR, HSP70 and HSF Binding Protein1 (HSBP1) interact with HSF1 and thus dissociate trimeric HSF1 into an inert monomeric form in humans. However, little is known about the effect of HSBP with thermal stress in plants. This report describes our investigation of the role of AtHSBP in Arabidopsis (Arabidopsis thaliana) by genetic and molecular approaches. AtHSBP was heat inducible and ubiquitously expressed in all tissues; AtHSBP was also crucial for seed development, as demonstrated by AtHSBP-knockout lines showing seed abortion. Thermotolerance results showed that AtHSBP participates in acquired thermotolerance but not basal thermotolerance and is a negative regulator of HSR. Subcellular localization revealed that the cytosol-localized AtHSBP translocated to the nucleus in response to HS. Protoplast two-hybrid assay results confirmed that AtHSBP interacts with itself and with the HSFs, AtHSFA1a, AtHSFA1b, and AtHSFA2. AtHSBP also negatively affected AtHSFA1b DNA-binding capacity in vitro. Quantitative polymerase chain reaction and western-blot analysis demonstrated that altered levels of AtHSBP lead to differential HSP expression, mainly during the recovery from HS. These studies provide a new insight into HSBP in plants and reveal that AtHSBP is a negative regulator of HSR and required for seed development.
Hsu
Shih-Feng
SF
Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei 10617, Taiwan.
Lai
Hui-Chuan
HC
Jinn
Tsung-Luo
TL
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D021381:Protein Transport; D012639:Seeds / Q000254:growth & development*; D016415:Sequence Alignment
D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D006360:Heat-Shock Proteins; C036483:T-DNA
Plant J. 2006 Nov;48(4):535-47
17059409
J Biol Chem. 2004 Feb 20;279(8):6401-13
14623884
Genetics. 2004 Jul;167(3):1381-94
15280250
Plant J. 2001 Jul;27(1):25-35
11489180
Nat Protoc. 2007;2(7):1565-72
17585298
Plant J. 2005 Jan;41(1):1-14
15610345
Plant Physiol. 2007 Jan;143(1):251-62
17085506
J Biol Chem. 2002 Jan 4;277(1):735-45
11679589
Eur J Cell Biol. 2010 Feb-Mar;89(2-3):126-32
19945192
Plant J. 1998 Dec;16(6):735-43
10069079
Cell Stress Chaperones. 2001 Jul;6(3):177-89
11599559
Cell Stress Chaperones. 2001 Jul;6(3):201-8
11599561
FASEB J. 2001 May;15(7):1118-31
11344080
Annu Rev Genet. 1988;22:631-77
2853609
Plant Physiol. 2006 Apr;140(4):1297-305
16500991
Proteins. 2009 Apr;75(1):1-11
18767159
Genes Dev. 1998 Jul 1;12(13):1962-74
9649501
J Exp Bot. 2003 Oct;54(391):2343-9
14504302
Biotechniques. 1997 May;22(5):861-2, 865
9149864
Proc Natl Acad Sci U S A. 2000 Apr 11;97(8):4392-7
10760305
Science. 1994 Jan 14;263(5144):224-7
8284672
Plant Physiol. 1998 Aug;117(4):1135-41
9701569
Gene. 1990 Nov 30;96(1):125-8
2265750
Plant Physiol. 2001 Jun;126(2):789-800
11402207
Gene. 1998 Oct 9;221(1):35-43
9852947
Mol Genet Genomics. 2004 Feb;271(1):11-21
14655047
J Exp Bot. 2002 Feb;53(367):371-5
11807141
Biol Chem. 2003 Jun;384(6):959-63
12887064
Planta. 2006 Jun;224(1):42-52
16331466
Genes Dev. 1998 Dec 15;12(24):3788-96
9869631
Plant J. 2004 May;38(3):432-47
15086804
Annu Rev Cell Dev Biol. 1995;11:441-69
8689565
Plant J. 2005 Jan;41(2):269-81
15634203
Mol Gen Genet. 1996 Aug 27;252(1-2):11-9
8804399
Plant Cell. 2000 Apr;12(4):479-92
10760238
Plant Physiol. 2005 Jun;138(2):882-97
15923322
Plant J. 2006 Jun;46(5):890-900
16709202
Genes Dev. 2002 Jun 15;16(12):1555-67
12080093
Plant Cell. 2002 Dec;14(12):3119-32
12468731
Plant Cell Physiol. 2008 Sep;49(9):1306-15
18641404
Annu Rev Genet. 1993;27:437-96
8122909
Science. 1993 Jan 8;259(5092):230-4
8421783
Plant Physiol. 2005 Sep;139(1):5-17
16166256
Annu Rev Biochem. 1986;55:1151-91
2427013