TY - JOUR
T1 - Mechanisms of hormonal regulation of endosperm cap-specific gene expression in tomato seeds
AU - Martínez-Andújar, Cristina
AU - Pluskota, Wioletta E.
AU - Bassel, George W.
AU - Asahina, Masashi
AU - Pupel, Piotr
AU - Nguyen, Theresa T.
AU - Takeda-Kamiya, Noriko
AU - Toubiana, David
AU - Bai, Bing
AU - Gõrecki, Ryszard J.
AU - Fait, Aaron
AU - Yamaguchi, Shinjiro
AU - Nonogaki, Hiroyuki
PY - 2012/8/1
Y1 - 2012/8/1
N2 - The micropylar region of endosperm in a seed, which is adjacent to the radicle tip, is called the 'endosperm cap', and is specifically activated before radicle emergence. This activation of the endosperm cap is a widespread phenomenon among species and is a prerequisite for the completion of germination. To understand the mechanisms of endosperm cap-specific gene expression in tomato seeds, GeneChip analysis was performed. The major groups of endosperm cap-enriched genes were pathogenesis-, cell wall-, and hormone-associated genes. The promoter regions of endosperm cap-enriched genes contained DNA motifs recognized by ethylene response factors (ERFs). The tomato ERF1 (TERF1) and its experimentally verified targets were enriched in the endosperm cap, suggesting an involvement of the ethylene response cascade in this process. The known endosperm cap enzyme endo-β-mannanase is induced by gibberellin (GA), which is thought to be the major hormone inducing endosperm cap-specific genes. The mechanism of endo-β-mannanase induction by GA was also investigated using isolated, embryoless seeds. Results suggested that GA might act indirectly on the endosperm cap. We propose that endosperm cap activation is caused by the ethylene response of this tissue, as a consequence of mechanosensing of the increase in embryonic growth potential by GA action.
AB - The micropylar region of endosperm in a seed, which is adjacent to the radicle tip, is called the 'endosperm cap', and is specifically activated before radicle emergence. This activation of the endosperm cap is a widespread phenomenon among species and is a prerequisite for the completion of germination. To understand the mechanisms of endosperm cap-specific gene expression in tomato seeds, GeneChip analysis was performed. The major groups of endosperm cap-enriched genes were pathogenesis-, cell wall-, and hormone-associated genes. The promoter regions of endosperm cap-enriched genes contained DNA motifs recognized by ethylene response factors (ERFs). The tomato ERF1 (TERF1) and its experimentally verified targets were enriched in the endosperm cap, suggesting an involvement of the ethylene response cascade in this process. The known endosperm cap enzyme endo-β-mannanase is induced by gibberellin (GA), which is thought to be the major hormone inducing endosperm cap-specific genes. The mechanism of endo-β-mannanase induction by GA was also investigated using isolated, embryoless seeds. Results suggested that GA might act indirectly on the endosperm cap. We propose that endosperm cap activation is caused by the ethylene response of this tissue, as a consequence of mechanosensing of the increase in embryonic growth potential by GA action.
KW - Solanum lycopersicum
KW - embryo
KW - endosperm
KW - ethylene
KW - germination
KW - gibberellin
KW - seed
UR - http://www.scopus.com/inward/record.url?scp=84864589120&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84864589120&partnerID=8YFLogxK
U2 - 10.1111/j.1365-313X.2012.05010.x
DO - 10.1111/j.1365-313X.2012.05010.x
M3 - Article
C2 - 22458548
AN - SCOPUS:84864589120
VL - 71
SP - 575
EP - 586
JO - Plant Journal
JF - Plant Journal
SN - 0960-7412
IS - 4
ER -