| Autor: |
Fernández-Herrera LJ; Centro Interdisciplinario de Ciencias Marinas (IPN-CICIMAR), Av. Instituto Politécnico Nacional s/n, Col. Playa Palo de Santa Rita, La Paz 23096, Mexico., Band-Schmidt CJ; Centro Interdisciplinario de Ciencias Marinas (IPN-CICIMAR), Av. Instituto Politécnico Nacional s/n, Col. Playa Palo de Santa Rita, La Paz 23096, Mexico., Zenteno-Savín T; Centro de Investigaciones Biológicas del Noroeste (CIBNOR), S.C. Instituto Politécnico Nacional 195, Col. Playa Palo Santa Rita, La Paz 23096, Mexico., Leyva-Valencia I; Consejo Nacional de Ciencia y Tecnología-Instituto Politécnico Nacional, Centro Interdisciplinario de Ciencias Marinas (CONACyT, IPN-CICIMAR), Col. Playa Palo de Santa Rita, La Paz 23096, Mexico., Hernández-Guerrero CJ; Centro Interdisciplinario de Ciencias Marinas (IPN-CICIMAR), Av. Instituto Politécnico Nacional s/n, Col. Playa Palo de Santa Rita, La Paz 23096, Mexico., Muñoz-Ochoa M; Centro Interdisciplinario de Ciencias Marinas (IPN-CICIMAR), Av. Instituto Politécnico Nacional s/n, Col. Playa Palo de Santa Rita, La Paz 23096, Mexico. |
| Abstrakt: |
Allelopathy between phytoplankton species can promote cellular stress and programmed cell death (PCD). The raphidophyte Chattonella marina var. marina , and the dinoflagellates Margalefidinium polykrikoides and Gymnodinium impudicum have allelopathic effects on Gymnodinium catenatum ; however, the physiological mechanisms are unknown. We evaluated whether the allelopathic effect promotes cellular stress and activates PCD in G. catenatum . Cultures of G. catenatum were exposed to cell-free media of C. marina var. marina , M. polykrikoides and G. impudicum . The mortality, superoxide radical (O 2 ●- ) production, thiobarbituric acid reactive substances (TBARS) levels, superoxide dismutase (SOD) activity, protein content, and caspase-3 activity were quantified. Mortality (between 57 and 79%) was registered in G. catenatum after exposure to cell-free media of the three species. The maximal O 2 ●- production occurred with C. marina var . marina cell-free media. The highest TBARS levels and SOD activity in G. catenatum were recorded with cell-free media from G. impudicum . The highest protein content was recorded with cell-free media from M. polykrikoides . All cell-free media caused an increase in the activity of caspase-3. These results indicate that the allelopathic effect in G. catenatum promotes cell stress and caspase-3 activation, as a signal for the induction of programmed cell death. |
