Ethylene signaling is required for synergid degeneration and the establishment of a pollen tube block.
Dev Cell
; 25(3): 310-6, 2013 May 13.
Article
in En
| MEDLINE
| ID: mdl-23673332
ABSTRACT
In flowering plants, sperm cells are delivered by pollen tubes, which are attracted by two egg-cell-adjoining synergids. Successful fertilization terminates pollen tube attraction; however, the underlying mechanisms are not understood. Here, we show that the process of fertilization activates an EIN3- and EIN2-dependent ethylene-response cascade necessary for synergid cell death and the concomitant establishment of a pollen tube block. Microinjection of the ethylene precursor ACC into the female gametophyte or constitutive ethylene response results in premature synergid disintegration. This indicates that the requirement of fertilization for synergid degeneration and associated establishment of a pollen tube block can be bypassed by mimicking a postfertilization ethylene burst. Surprisingly, the persistent synergid in ethylene-hyposensitive plants adopts the molecular profile and cell-cycle regime of the biparental embryo-nourishing tissue, suggesting that ethylene signaling prevents the formation of an asexual maternal endosperm fraction.
Full text:
1
Database:
MEDLINE
Main subject:
Signal Transduction
/
Ethylenes
/
Pollen Tube
/
Fertilization
Language:
En
Journal:
Dev Cell
Journal subject:
EMBRIOLOGIA
Year:
2013
Type:
Article
Affiliation country:
Germany