Month: September 2022

THE SELF TEST. "During the various phases of pollination, angiosperms distinguish self from non-self-pollen and direct and control pollen tube growth through the maternal tissues towards the egg apparatus." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

INBREEDING CHECK. "During this journey, the pollen tube of Arabidopsis, for example, interacts with at least seven different pistil cell types prior to arrival at its final destination inside the ovule. To add complexity, further layers of recognition exist. These include self-recognition and specialized processes to prevent self-fertilization and consequent inbreeding, as well as interspecific barriers, which are poorly understood at the molecular/cellular level." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

POLLEN-PISTIL CHAT. "Transcriptomic analyses have recently revealed an unsurpassed level of complex gene regulation relating to pollen–pistil interactions. Microarray analysis revealed that the transcriptome of Arabidopsis pollen tubes that have grown through pistil tissues using a semi-in vivo pollen tube growth system is significantly distinct from transcriptomes of pollen grains or pollen tubes grown in vitro, and implicate de novo gene expression in pollen tubes due to interactions with the female tissues." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

GENETIC EXPLOSION IN POLLEN TUBE. "Thus, in contrast to the handful of gene expression changes during hydration, a very large number of gene expression changes occur when pollen tubes grow through pistil tissues. For example, over 1000 genes had significantly different expression in comparisons between semi-in vivo-grown pollen tubes and dry pollen, and a similar number after 4-h pollen tube growth; expression of a unique set of 383 pollen tube-expressed proteins present in pistil-interacted pollen tubes were identified." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

PAYLOAD DELIVERY. "Intensive gamete crosstalk takes place and, after a process involving recognition, sperm activation, and adhesion of plasma membranes, both gamete pairs fuse (plasmogamy) and sperm contents are released inside female gametes." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

SINGLE SPERM EVENT. "Once double fertilization has been successfully achieved, it is important to establish barriers to prevent the attraction of additional pollen tubes and to prevent the release and fusion of multiple sperm with single gametes." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

RACE OF THE POLLEN TUBES. "In the grasses, multiple pollen tubes exit the transmitting tract in a race to reach the female gametophyte. The fastest-growing pollen tube penetrates the micropyle and releases its contents into the receptive synergid. Additional pollen tubes seem to be repelled, as heterofertilization, which indicates that sperm cells of two different pollen tubes have fused with both female gametes, is very rare in maize (about 1%)." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

COCKTAIL PARTY HUBBUB. "More general signaling molecules involved in regulation of many of the pollination processes have also been identified. Ca2+ is now well established as playing a central role, acting in a signaling capacity during pollen germination, pollen tube growth, SI responses, and gamete reception." http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

IONOSPHERE. "Ca2+ is important as an intracellular second messenger in the fertilization of many organisms. In animals including mouse, xenopus, ascidian, starfish and sea urchin, various patterns of cytosolic Ca2+ waves and oscillations are involved in fertilization and the subsequent onset of embryogenesis." https://lnkd.in/dXVTT6X View in LinkedIn

WAVES OF IONS. "Ca2+ waves and oscillation are key signalling elements during the fertilization process of animals, and are involved, for example, in egg activation. In the unique double fertilization process in flowering plants, both the egg cell and the neighbouring central cell fuse with a sperm cell each. Here we succeeded in imaging cytosolic Ca2+ in these two cells, and in the two synergid cells that accompany the gametes during semi-in vivo double fertilization." https://lnkd.in/dXVTT6X View in LinkedIn