This would imply that kleptocnides are rendered rather useless after a few days and new nematocysts have to be incorporated and matured. Published data on long term retention and maintenance

of functional kleptocnides (Greenwood and Mariscal, Rucaparib manufacturer 1984a; Greenwood et al., 1989; Greenwood, 2009) contradict this hypothesis. Second, Ageladine A is a dye with its highest intensity at around pH 3–4. A further decrease of the pH value hence could imply a subsequent decrease of the intensity. This has not been studied in detail yet. Members of some gastropod taxa are able to produce acids of pH values lower than 2 (Edmunds, 1968; Thompson, 1960, 1988). It seems likely that aeolids are also able to produce high amounts of protons. Therefore the dye’s properties in tissues known to exhibit extreme low pH values needs to be tested. Third, according to Berking and Herrmann (2005), the free protons are bound onto the poly-γ-glutaminacids in the capsule matrix after transport into the capsule. This implies a lower number of free protons after 72 h that could bind MK-2206 purchase onto the guanidine moiety of the Ageladine. In consequence a lower fluorescence

intensity of the Ageladine A due to a reduced number of free protons is observed after 3 days. It has to be emphasized here that nematocysts in the acontia of Aiptasia showed a high fluorescence, and we assume that these are mature and capable of discharge. Nevertheless, some of the nematocysts in the same sample ( Fig. 2A and further results) showed a higher intensity. This reflects the same situation we find in the cnidosacs with a high fluorescence after 2–3 days but a decrease after 4 days. Due to the chosen photomultiplier value of 500 V in the experiments with Aeolidiella, many fluorescence values of the measured kleptocnides were

out of the maximal range and exhibited fluorescence intensities higher than 255 i.u. at the later time intervals. To show a better resolution of the acidification OSBPL9 in later maturation stages, a lower photomultiplier setting is necessary, as can be seen in the first experiments with Aiptasia. However, lower photomultiplier setting result in little or no visibility of kleptocnides in the earlier time intervals because of their low fluorescence due to a still rather high pH value. Irrespective of this drawback of chosen accommodations, we were able to show the rising fluorescence and therefore decrease of pH values of kleptocnides after incorporation into the cnidosac. The comparison with control gastropods investigated with higher photomultiplier settings also show, that kleptocnides in the cnidosac exhibit various intensities of fluorescence connected with various stages of maturity. This would explain why only some of the kleptocnides discharge during handling the gastropod and others do not ( Fig. 1D).