Molecular mechanisms and hormonal regulation underpinning morphological dormancy: a case study using Apium graveolens (Apiaceae)

0552931 - ÚEB 2022 RIV GB eng J - Článek v odborném periodiku
Walker, M. - Pérez, M. - Steinbrecher, T. - Gawthrop, F. - Pavlović, Iva - Novák, Ondřej - Tarkowská, Danuše - Strnad, Miroslav - Marone, F. - Nakabayashi, K. - Leubner-Metzger, Gerhard
Molecular mechanisms and hormonal regulation underpinning morphological dormancy: a case study using Apium graveolens (Apiaceae).
Plant Journal. Roč. 108, č. 4 (2021), s. 1020-1036. ISSN 0960-7412. E-ISSN 1365-313X
Grant CEP: GA MŠMT(CZ) EF16_019/0000827; GA MŠMT(CZ) EF16_019/0000738; GA ČR(CZ) GA18-10349S
Institucionální podpora: RVO:61389030
Klíčová slova: ABA-gibberellin balance * Apium graveolens (celery) * auxin transport * dormancy evolution * embryo growth * endosperm breakdown * morphological dormancy * underdeveloped embryo
Obor OECD: Plant sciences, botany
Impakt faktor: 7.091, rok: 2021
Způsob publikování: Open access
http://doi.org/10.1111/tpj.15489

Underdeveloped (small) embryos embedded in abundant endosperm tissue, and thus having morphological dormancy (MD) or morphophysiological dormancy (MPD), are considered to be the ancestral state in seed dormancy evolution. This trait is retained in the Apiaceae family, which provides excellent model systems for investigating the underpinning mechanisms. We investigated Apium graveolens (celery) MD by combined innovative imaging and embryo growth assays with the quantification of hormone metabolism, as well as the analysis of hormone and cell-wall related gene expression. The integrated experimental results demonstrated that embryo growth occurred inside imbibed celery fruits in association with endosperm degradation, and that a critical embryo size was required for radicle emergence. The regulation of these processes depends on gene expression leading to gibberellin and indole-3-acetic acid (IAA) production by the embryo and on crosstalk between the fruit compartments. ABA degradation associated with distinct spatiotemporal patterns in ABA sensitivity control embryo growth, endosperm breakdown and radicle emergence. This complex interaction between gibberellins, IAA and ABA metabolism, and changes in the tissue-specific sensitivities to these hormones is distinct from non-MD seeds. We conclude that the embryo growth to reach the critical size and the associated endosperm breakdown inside MD fruits constitute a unique germination programme.
Trvalý link: http://hdl.handle.net/11104/0327996