After mimicking
the desiccation of G. arbuscula p38 MAPK signaling pathway thalli experienced during low tides, the volatile compounds emitted were trapped in the headspace of 2 mL glass vials for 1 h. Two methods based on gas chromatography/mass spectrometry revealed that the range of organic volatile compounds released was affected by abiotic factors, such as the availability and spectral quality of light, salinity, and exogenous ethylene. Amines and methyl alkyl compounds were produced after exposure to white light and darkness but not after exposure to exogenous ethylene or red light. Volatiles potentially associated with the oxidation of fatty acids, such as alkenes and low-molecular-weight oxygenated compounds, accumu-lated after exposure to exogenous ethylene and red light. Ethylene was produced in all treatments, especially after exposure to exogenous ethylene.
Levels of DMS, the most abundant sulfur-compound that was emitted in all of the conditions tested, did not increase after incubation with ethylene. Thus, although DMSP lyase is active in G. arbuscula, selleck products it is unlikely to contribute to ethylene synthesis. The generation of ethylene and DMS do not appear to be coordinated in G. arbuscula. “
“The marine photosynthetic dinoflagellates Dinophysis Ehrenb. species are obligate mixotrophs that require both light and the ciliate prey Myrionecta rubra (= Mesodinium rubrum) for long-term survival. Despite rapid progress on the study of Dinophysis using laboratory cultures, however, whether it has its own permanent plastids or kleptoplastids (i.e., stolen plastids from its ciliate prey) is not fully resolved. Here, we addressed this issue using established cultures of D. caudata Saville-Kent strain DC-LOHABE01 and cross-feeding/starvation experiments encompassing the prey M. rubra strain MR-MAL01 cultures grown on two different cryptophytes (strains CR-MAL01
and CR-MAL11). 5-FU cell line To follow the fate of prey plastids, psbA gene as a tracer was amplified from individually isolated D. caudata cells, and the PCR products were digested with a restriction enzyme, SfaNI. The RFLP pattern of the PCR products digested by SfaNI revealed that D. caudata continued to keep CR-MAL01–type plastids, while it lost CR-MAL11–type plastids with increasing starvation time. Our results suggest that Dinophysis treats in different ways plastids taken up from different cryptophytes via its ciliate prey M. rubra. Alternatively, D. caudata may already have its own CR-MAL01–type permanent plastid, with two types of plastids (CR-MAL01 and CR-MAL11) obtained from M. rubra being lost within 1 month. This result highlights the need to identify more accurately the origin of plastids in newly isolated photosynthetic Dinophysis species to resolve the issue of plastid permanence.