Thesis (Ph.D) - University of Birmingham, School of Biological Sciences.
|Statement||by Kamaljit Kaur Atwal.|
Turning to look at the pollen side, we have used the in vitro system to study the metabolic events occurring in the pollen of P. rhoeas as a consequence of the SI reaction. We have determined that it requires both de novo glyco-sylation and RNA transcription for full inhibition of pollen-tube growth during the SI by: Studies of the molecular and biochemical basis of self‐incompatibility (SI) in Papaver rhoeas have revealed much about the signalling pathways triggered in pollen early in this response. The aim of the current investigation was to begin to study downstream events in order to elucidate some of the later cellular responses involved in the SI response and identification of the mechanisms Cited by: Abstract Self-incompatibility (SI) is a genetically controlled system used by many flowering plants to prevent self-pollination. We established, using calcium imaging, that the SI response in. inhibition of Papaver pollen tube growth through the SI reaction (Franklin-Tong et al., ), with incompatible S proteins acting as signal molecules (Franklin-Tong et al., ). Subsequently, ratiometric Ca 2+ -imaging provided more detailed information and accurate.
Self-incompatibility (SI) is a genetically-controlled system used by many flowering plants to prevent self-fertilization. We have been investigating SI in Papaver rhoeas for a number of years, and have begun to build up a picture of some of the signalling events and mechanisms involved in this specific inhibition of pollen tube growth. Mitogen-activated protein kinases (MAPKs) operate downstream of receptor–ligand interactions, playing a pivotal role in responses to extracellular signals. The self-incompatibility (SI) response in Papaver rhoeas L. triggers a Ca 2+-dependent signalling cascade resulting in inhibition of incompatible pollen. signalling pathway is implicated in the SI response. Keywords Calcium influx Calcium signalling Inositide signalling Pollen Self-incompatibility Introduction Self-incompatibility (SI) is a mechanism used by many flowering plants to prevent self-pollination. In Papaver rhoeas L., var. Shirley, SI is controlled by a single, multi-. Self-incompatibility (SI) is used by many angiosperms to reject self-pollen and avoid inbreeding. In field poppy (Papaver rhoeas), SI recognition and rejection of self-pollen is facilitated by a female S -determinant, PrsS, and a male S -determinant, PrpS. PrsS belongs to the cysteine-rich peptide family, whose members activate diverse signaling networks involved in plant growth, defense.
In Papaver rhoeas, PrsS proteins encoded by the pistil S-determinant interact with incompatible pollen to effect inhibition of pollen growth via a Ca(2+)-dependent signalling network, resulting in programmed cell death of 'self' pollen. Recent studies are described here that identified and characterized the pollen S-determinant of SI in P. rhoeas. Self-incompatibility (SI) in Papaver rhoeas is accompanied by a cascade of signalling events that result in the rapid arrest and eventual death of the pollen tube. We have used rapid freeze. Mechanistically, one of the best-studied SI systems is that of Papaver rhoeas (poppy), which involves the interaction between the two S -determinants, a stigma-expressed secreted protein (PrsS) and a pollen-expressed plasma membrane-localized protein (PrpS). SI inhibition of pollen tube growth could be regarded as a stress response, so it was speculated that MAPKs might be involved in the SI response . (SI) response in Papaver rhoeas L. has.