Epigenetic chromatin modifiers in barley: IV. The study of barley polycomb group (PcG) genes during seed development and in response to external ABA.
BACKGROUND
Epigenetic phenomena have been associated with the regulation of active and silent chromatin states achieved by modifications of chromatin structure through DNA methylation, and histone post-translational modifications. The latter is accomplished, in part, through the action of PcG (Polycomb group) protein complexes which methylate nucleosomal histone tails at specific sites, ultimately leading to chromatin compaction and gene silencing. Different PcG complex variants operating during different developmental stages have been described in plants. In particular, the so-called FIE/MEA/FIS2 complex governs the expression of genes important in embryo and endosperm development in Arabidopsis. In our effort to understand the epigenetic mechanisms regulating seed development in barley (Hordeum vulgare), an agronomically important monocot plant cultivated for its endosperm, we set out to characterize the genes encoding barley PcG proteins.


RESULTS
Four barley PcG gene homologues, named HvFIE, HvE(Z), HvSu(z)12a, and HvSu(z)12b were identified and structurally and phylogenetically characterized. The corresponding genes HvFIE, HvE(Z), HvSu(z)12a, and HvSu(z)12b were mapped onto barley chromosomes 7H, 4H, 2H and 5H, respectively. Expression analysis of the PcG genes revealed significant differences in gene expression among tissues and seed developmental stages and between barley cultivars with varying seed size. Furthermore, HvFIE and HvE(Z) gene expression was responsive to the abiotic stress-related hormone abscisic acid (ABA) known to be involved in seed maturation, dormancy and germination.


CONCLUSIONS
This study reports the first characterization of the PcG homologues, HvFIE, HvE(Z), HvSu(z)12a and HvSu(z)12b in barley. All genes co-localized with known chromosomal regions responsible for malting quality related traits, suggesting that they might be used for developing molecular markers to be applied in marker assisted selection. The PcG differential expression pattern in different tissues and seed developmental stages as well as in two barley cultivars with different seed size is suggestive of a role for these genes in barley seed development. HvFIE and HvE(Z) were also found to be induced by the plant hormone ABA implying an association with ABA-mediated processes during seed development, germination and stress response.
Kapazoglou
Aliki
A
Institute of Agrobiotechnology, CERTH, Thermi-Thessaloniki, Greece.
Tondelli
Alessandro
A
Papaefthimiou
Dimitra
D
Ampatzidou
Helen
H
Francia
Enrico
E
Stanca
Michele A
MA
Bladenopoulos
Konstantinos
K
Tsaftaris
Athanasios S
AS
D000040:Abscisic Acid / Q000494:pharmacology*; D000595:Amino Acid Sequence; D002843:Chromatin / Q000235:genetics*; D002874:Chromosome Mapping; D044127:Epigenesis, Genetic / Q000187:drug effects*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D017343:Genes, Plant / Q000235:genetics; D001467:Hordeum / Q000235:genetics* / Q000254:growth & development; D008969:Molecular Sequence Data; D009929:Organ Size / Q000187:drug effects / Q000235:genetics; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D010802:Phylogeny; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000187:drug effects / Q000235:genetics; D012639:Seeds / Q000033:anatomy & histology / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D002843:Chromatin; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins; D000040:Abscisic Acid
Plant Cell. 2006 Jan;18(1):119-32
16326929
Trends Cell Biol. 2008 May;18(5):236-43
18375123
Curr Biol. 2006 Mar 7;16(5):486-92
16527743
EMBO J. 2006 Oct 4;25(19):4638-49
16957776
J Integr Plant Biol. 2008 Oct;50(10):1187-95
19017106
Cell. 2006 Feb 10;124(3):495-506
16469697
Genes Dev. 2003 Jun 15;17(12):1540-53
12815071
Plant Cell. 1999 Oct;11(10):1945-52
10521524
Nature. 2007 Jul 19;448(7151):349-52
17637669
Nucleic Acids Res. 2002 May 1;30(9):e36
11972351
Nat Genet. 2005 Jan;37(1):28-30
15619622
Methods Mol Biol. 2000;132:365-86
10547847
Development. 2004 Nov;131(21):5263-76
15456723
Plant Physiol. 2008 Apr;146(4):1738-58
18281415
Plant Physiol. 2002 Apr;128(4):1332-45
11950982
Plant Cell. 2009 Feb;21(2):386-402
19244142
Curr Opin Plant Biol. 2009 Apr;12(2):133-9
19179104
Plant Cell. 2008 Nov;20(11):2972-88
19033529
Plant Cell. 2002;14 Suppl:S15-45
12045268
Mol Biol Evol. 1987 Jul;4(4):406-25
3447015
Brief Bioinform. 2004 Jun;5(2):150-63
15260895
Mol Plant. 2009 Jul;2(4):711-723
19825651
Gene. 2003 Sep 18;314:1-13
14527713
Proc Natl Acad Sci U S A. 1999 Mar 30;96(7):4186-91
10097185
Proc Natl Acad Sci U S A. 2006 Sep 26;103(39):14631-6
16983073
Plant J. 2006 Apr;46(1):124-33
16553900
Plant J. 1998 May;14(3):387-92
9628033
Biochem Biophys Res Commun. 2007 May 18;356(4):843-50
17399684
Plant Cell. 2004;16 Suppl:S203-13
15010515
Curr Opin Genet Dev. 2004 Apr;14(2):155-64
15196462
Cell. 2008 Mar 7;132(5):735-44
18329361
Plant Cell. 1999 Mar;11(3):407-16
10072400
Cell. 2007 Feb 23;128(4):635-8
17320500
Plant Cell. 2000 Dec;12(12):2367-2382
11148284
EMBO Rep. 2006 Sep;7(9):947-52
16878125
Plant J. 2007 Dec;52(5):927-36
17892443
Plant Cell. 2004;16 Suppl:S214-27
15010513
Science. 1998 Apr 17;280(5362):446-50
9545225
Plant Cell. 2003 Feb;15(2):425-38
12566582
Theor Appl Genet. 2007 Feb;114(3):487-500
17115126
Plant Mol Biol. 2001 Feb;45(3):327-40
11292078
Bioinformatics. 2003 Aug 12;19(12):1572-4
12912839
Development. 2001 Sep;128(17):3371-9
11546753
Nature. 2004 Jan 8;427(6970):159-64
14712276
EMBO J. 2003 Sep 15;22(18):4804-14
12970192
Cell. 2009 Jan 23;136(2):200-6
19167321
Plant Physiol Biochem. 2010 Feb-Mar;48(2-3):98-107
20117010
Biochim Biophys Acta. 2007 May-Jun;1769(5-6):295-307
17556080
Development. 2004 Jun;131(12):2971-81
15151989
Proc Natl Acad Sci U S A. 2000 Sep 12;97(19):10637-42
10962025
Physiol Plant. 2009 Jul;136(3):358-68
19470089
Annu Rev Plant Biol. 2005;56:165-85
15862093
Plant Cell Physiol. 2008 Sep;49(9):1263-71
18701524
Nucleic Acids Res. 1994 Nov 11;22(22):4673-80
7984417
Development. 2000 Jun;127(11):2493-502
10804189
J Mol Biol. 1990 Oct 5;215(3):403-10
2231712
Semin Cell Dev Biol. 2008 Dec;19(6):547-53
18718547
J Cell Sci. 2008 Mar 15;121(Pt 6):906-12
18303047
Curr Biol. 2000 Nov 30;10(23):1535-8
11114524
Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13244-9
16924116
Comput Appl Biosci. 1996 Aug;12(4):357-8
8902363