1 research outputs found
Scrippsiella acuminata versus Scrippsiella ramonii: A Physiological Comparison
12 pages, 6 figures.-- Open accessScrippsiella is a cosmopolitan dinoflagellate genus that is able to form Harmful Algal
Blooms in coastal waters. The large physiological, morphological, and genetic variability
that characterizes this genus suggest the existence of cryptic species. In this study,
flow cytometric analyses were carried out to compare the cell cycle and life cycle of
two Scrippsiella strains from two different species: Scrippsiella ramonii (VGO1053) and
Scrippsiella acuminata (S3V). Both species were also investigated by internally transcribed
spacer rDNA sequencing and high-performance liquid chromatography-based
pigment analyses. The reddish-brown color of S. acuminata and yellowish-green hue
of S. ramonii were consistent with the quantitative differences determined in their pigment
profiles. Our results indicate that the cell cycle is light-controlled and that it differs
in the two species. S-phase was detected during the light period in both, whereas
the G2/M phase occurred during the light period in S. ramonii but under dark conditions
in S. acuminata. The detection of 4C stages, mobile zygotes (planozygotes), and
resting cysts in S. ramonii (nonclonal) provided convincing evidence of sexuality in
this species. Sexual related processes were not found in the clonal S. acuminata strain,
suggesting its heterothallic behavior (i.e., the need for outcrossing). The differences in
the genome size of these species were examined as wellThe present work was funded by the FORMAS (Sweden)
project (Formas 215-2010-824), CCVIEO and CIGUATROP
projects of the Instituto Español de Oceanografía and the
Spanish project “Tropicalización y ciguatera en Canarias”
funded by the Fundación BiodiversidadPeer reviewe