Molecular Biology and Evolution, Vol 13, 1192-1197, Copyright © 1996 by Society for Molecular Biology and Evolution
RJ Gast and DA Caron
Recent analyses of the small subunit ribosomal DNA (srDNA) from
dinoflagellate symbionts of cnidaria have confirmed historical descriptions
of a diverse but well-defined clade, Symbiodinium, as well as several other
independent symbiont lineages (Rowan 1991; Rowan and Powers 1992; Sadler et
al. 1992; McNally et al 1994). Dinoflagellates also occur as intracellular
symbionts in a number of pelagic protistan taxa, but the srDNA of these
symbionts has not been examined. We analyzed the srDNA sequences of the
symbiotic dinoflagellates from four planktonic foraminiferal species and
six radiolarian species. The symbionts from these sarcodines formed two
distinct lineages within the dinoflagellates. Within each lineage,
symbionts obtained from different host species showed few, if any, srDNA
sequence differences. The planktonic foraminiferal symbionts were most
closely related to Gymnodinium simplex and the Symbiodinium clade, whereas
the radiolarian symbionts were most closely related to the dinoflagellate
symbiont from the oceanic chondrophore, Velella velella. Therefore,
although the dinoflagellate symbionts of foraminifera appear to be a sister
taxon of the symbionts from benthic foraminifera and invertebrates, the
symbionts of radiolaria are distinct and arose from an independent lineage
of dinoflagellate symbionts that shares common ancestry with the symbiont
of at least one pelagic metazoan. The lack of srDNA variability within the
sarcodine symbiont lineages suggests that coevolution of host and symbiont
has not occurred.
ORIGINAL ARTICLE
Molecular phylogeny of symbiotic dinoflagellates from planktonic foraminifera and radiolaria
Biology Department, Woods Hole Oceanographic Institution, Massachusetts 02543, USA. rgast@whoi.edu
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
H. C. W. Skinner Biominerals Mineralogical Magazine, October 1, 2005; 69(5): 621 - 641. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. J. Gast, D. J. Beaudoin, and D. A. Caron Isolation of Symbiotically Expressed Genes From the Dinoflagellate Symbiont of the Solitary Radiolarian Thalassicolla nucleata Biol. Bull., April 1, 2003; 204(2): 210 - 214. [Abstract] [Full Text] [PDF] |
||||
![]() |
Endosymbiont change as a key innovation in the adaptive radiation of Soritida (Foraminifera) Paleobiology, June 1, 2001; 27(2): 262 - 289. |
||||
![]() |
J. W. Stiller and B. D. Hall The origin of red algae: Implications for plastid evolution PNAS, April 29, 1997; 94(9): 4520 - 4525. [Abstract] [Full Text] [PDF] |
||||



