The unicellular green alga Dunaliella salina Teod. as a model - Algae

Algae 2011, 26(1): 3-20
years to the complete genome sequencing of about a dozen
microalgal species and a number of genome projects
are currently in progress for several other algae (http://
www.jgi.doe.gov). Indeed one of the earliest algal genomes
sequenced, C. reinhardtii’s, serve as an important
reference and a guidepost for further molecular analyses
(Grossman et al. 2007, Merchant et al. 2007). Research on
this unicellular green alga and two diatom species, whose
genomes have recently been sequenced, are now in the
post-genomics stage (Armbrust et al. 2004, Montsant et
al. 2007, Siaut et al. 2007). Despite the considerable available
molecular data regarding these microscopic photosynthetic
organisms, further biotechnology development
is necessary for overall algal commercial exploitation.
With the recent publication of the mitochondrial and
plastid genomes of D. salina (Smith et al. 2010) and the
forthcoming release of the nuclear genome by JGI, genome-based
and other approaches will become possible
in the near future. For example, development of microarrays
or deep cDNA sequencing methods (Margulies et al.
2005) can be expected to follow in short order and allow
comparative analysis of the transcriptome of cells exposed
to various environmental conditions. These techniques
will allow the study of multiple cellular processes
at the molecular level as, for example, the dissection of
the regulatory mechanisms involved in carotenogenesis
and glycerol metabolism. Furthermore, combining genomics
of D. salina with proteomics will facilitate analysis
of the structure and function of the unique glycocalyx
and the plasma membrane of this halotolerant organism.
In comparison to the alga C. reinhardtii, more genomic
tool development is still necessary for its close relative,
D. salina. At this time highly efficient transformation
systems are not available and genetic crosses cannot be
performed on a routine basis. However, with the genome
sequence becoming available soon, the alga D. salina as
a model system is about to undergo a major transformation.
The short-term outcome of research on this industrially
important species will allow not only an enhanced
understanding of complex metabolic networks, but also
further development of transgenic algal strains for particular
commercial applications (e.g., production of carotenoids
and recombinant proteins).
ACKNOWLEDGEMENTS
AR was supported by the Fundação para a Ciência
e Tecnologia, Portugal, with the studentship SFRH/
BD/13937/2003. Part of the work here described was
DOI: 10.4490/algae.2011.26.1.003 12
financed by the Portuguese National Budget and the
projects POCTI/MAR/15237/99 and INTERREG159-SAL-
Atlantic Salt Ponds awarded to JCV; by funding from the
Department of Transportation SunGrant Initiative (to
JCC) and NIH Grant P20 RR-016464 from the INBRE Program
of the National Center for Research Resources supporting
the Nevada Genomics, Proteomics and Bioinformatics
Center, and the Nevada Agricultural Experiment
Station; and was supported in part by a grant from the
Development of Marine-Bioenergy program funded by
Ministry of Land, Transport and Maritime Affairs of the
Korean Government.
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