caa a22 4500 397522215 CHVBK 20180308164636.0 cr unu---uuuuu 161202e199508 xx s 000 0 eng 10.1093/jxb/46.8.973 doi (NATIONALLICENCE)oxford-10.1093/jxb/46.8.973 Lithium-sensitive calcium activity in the germination of apple (Malus × domestica Borkh.), tobacco (Nicotiana tabacum L.), and potato (Solanum tuberosum L.) pollen [Elektronische Daten] [L. Zonia, J. Tupy] We have investigated Ca2+ activity during pollen germination and the possibility that it may be responding to a phosphoinositide signal transduction pathway, by employing inhibitors of Ca2+ channels (verapamil and TMB-8), EGTA as a Ca2+ scavenger and the inositol 1-phosphatase inhibitor lithium chloride. We have found that at least two Ca2+ pools are utilized during pollen germination. Influx of extracellular Ca2+ appears to be necessary for the germination of apple and tobacco pollen, but it does not appear to be required for the germination of potato pollen. Conversely, activation of intracellularly stored Ca2+ was necessary for optimal germination of all three pollen species. LiCI had strong effects on pollen germination. At 5 mM LiCI, pollen germination was inhibited by 78% for apple, 84% for tobacco, and 74% for potato. Li+ inhibition was overcome by the addition of Ca2+, which restores germination of all three species to 85-100% of that observed in controls, myo-lnositol also partially overcomes Li+ inhibition of pollen germination, thus providing some evidence for a link between Li+ inhibition and Ca2+ rescue, myo-lnositol rescue of Li+ inhibition was most effective for potato pollen. Chlorotetracycline (CTC) spectroscopy revealed a higher level of membrane-Ca2+ in Li + -treated pollen grains than in controls, and the short pollen tubes which did emerge did not accumulate membrane-associated Ca2+. The results suggest that Li+ inhibition may interfere with the release (activation) or partitioning of membrane-Ca2+ during pollen germination and that this Ca2+ activity may be responding, at least in part, with a phosphoinositide signal transduction pathway. © Oxford University Press Research Papers nationallicence Pollen germination nationallicence lithium inhibition nationallicence calcium nationallicence inositol nationallicence calcium inhibitors nationallicence Zonia L. Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Pernikářce 15, CZ-160 00 Prague 6, Czech Republic aut Tupy J. Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Pernikářce 15, CZ-160 00 Prague 6, Czech Republic aut Journal of Experimental Botany Oxford University Press 46/8(1995-08), 973-979 0022-0957 46:8<973 1995 46 exbotj https://doi.org/10.1093/jxb/46.8.973 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jxb/46.8.973 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zonia L. Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Pernikářce 15, CZ-160 00 Prague 6, Czech Republic aut NATIONALLICENCE 700 1- Tupy J. Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Pernikářce 15, CZ-160 00 Prague 6, Czech Republic aut NATIONALLICENCE 773 0- Journal of Experimental Botany Oxford University Press 46/8(1995-08), 973-979 0022-0957 46:8<973 1995 46 exbotj Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford