Comparative gene expression in toxic versus non-toxic strains of the marine dinoflagellate Alexandrium minutum.
BACKGROUND
The dinoflagellate Alexandrium minutum typically produces paralytic shellfish poisoning (PSP) toxins, which are known only from cyanobacteria and dinoflagellates. While a PSP toxin gene cluster has recently been characterized in cyanobacteria, the genetic background of PSP toxin production in dinoflagellates remains elusive.


RESULTS
We constructed and analysed an expressed sequence tag (EST) library of A. minutum, which contained 15,703 read sequences yielding a total of 4,320 unique expressed clusters. Of these clusters, 72% combined the forward-and reverse reads of at least one bacterial clone. This sequence resource was then used to construct an oligonucleotide microarray. We analysed the expression of all clusters in three different strains. While the cyanobacterial PSP toxin genes were not found among the A. minutum sequences, 192 genes were differentially expressed between toxic and non-toxic strains.


CONCLUSIONS
Based on this study and on the lack of identified PSP synthesis genes in the two existent Alexandrium tamarense EST libraries, we propose that the PSP toxin genes in dinoflagellates might be more different from their cyanobacterial counterparts than would be expected in the case of a recent gene transfer. As a starting point to identify possible PSP toxin-associated genes in dinoflagellates without relying on a priori sequence information, the sequences only present in mRNA pools of the toxic strain can be seen as putative candidates involved in toxin synthesis and regulation, or acclimation to intracellular PSP toxins.
Yang
Ines
I
Alfred-Wegener-Institut für Polar-und Meeresforschung, Bremerhaven, Germany.
John
Uwe
U
Beszteri
Sára
S
Glöckner
Gernot
G
Krock
Bernd
B
Goesmann
Alexander
A
Cembella
Allan D
AD
D004141:Dinoflagellida / Q000235:genetics* / Q000378:metabolism; D020224:Expressed Sequence Tags; D020869:Gene Expression Profiling; D008387:Marine Toxins / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D057096:Shellfish Poisoning / Q000382:microbiology
D008387:Marine Toxins
J Eukaryot Microbiol. 2007 Sep-Oct;54(5):427-35
17910687
Photochem Photobiol Sci. 2008 Feb;7(2):208-11
18264588
Appl Environ Microbiol. 2003 Jan;69(1):659-62
12514056
Yeast. 2006 May;23(7):553-71
16710832
BMC Mol Biol. 2007 Oct 04;8:87
17915037
Mar Biotechnol (NY). 2005 Sep-Oct;7(5):481-93
15976935
BMC Genomics. 2005 May 29;6:80
15921535
Protist. 2008 Jan;159(1):21-30
17931970
BMC Biochem. 2009 Mar 30;10:8
19331657
J Nat Toxins. 2000 Nov;9(4):409-17
11126517
Proc Natl Acad Sci U S A. 2007 Mar 13;104(11):4618-23
17360573
Methods Enzymol. 2006;411:134-93
16939790
Curr Biol. 2006 Sep 19;16(18):1857-64
16979565
Mol Biol Evol. 2001 Mar;18(3):418-26
11230543
PLoS One. 2010 Feb 16;5(2):e9235
20169071
Appl Environ Microbiol. 2000 May;66(5):2105-12
10788388
Proc Biol Sci. 2006 Jul 7;273(1594):1673-80
16769640
J Exp Mar Biol Ecol. 2001 Jul 30;262(2):177-197
11445086
Annu Rev Microbiol. 1996;50:431-65
8905087
Protist. 2008 Jul;159(3):471-82
18467171
PLoS One. 2008 Aug 13;3(8):e2929
18698341
Can J Microbiol. 1962 Apr;8:229-39
13902807
J Sep Sci. 2007 Aug;30(12):1821-6
17638360
Nucleic Acids Res. 2005 Jul 1;33(Web Server issue):W677-80
15980561
Biochim Biophys Acta. 1994 Oct 18;1219(2):449-56
7918642
Appl Environ Microbiol. 2008 Jul;74(13):4044-53
18487408
Mol Biol Evol. 2008 Jul;25(7):1307-20
18367465
FEMS Microbiol Ecol. 2001 Jul;36(2-3):223-234
11451527
Appl Environ Microbiol. 2007 May;73(10):3333-42
17337562
J Mol Evol. 2001 Sep;53(3):204-13
11523007
J Mol Biol. 2005 May 13;348(4):1015-24
15843030
J Mol Evol. 2008 Nov;67(5):526-38
18850059
Toxicon. 2004 Feb;43(2):149-58
15019474
Appl Environ Microbiol. 2005 Jul;71(7):3483-94
16000752
Syst Biol. 2003 Oct;52(5):696-704
14530136
Gene. 2003 Dec 4;321:73-81
14636994
Mar Biotechnol (NY). 2008 Nov-Dec;10(6):692-700
18478293
Nucleic Acids Res. 1997 Sep 1;25(17):3389-402
9254694
Proc Natl Acad Sci U S A. 2001 Apr 24;98(9):5116-21
11309499
Nature. 2001 Feb 15;409(6822):860-921
11237011
Biol Cell. 2006 Dec;98(12):709-20
16875467
Photochem Photobiol. 2004 Jul-Aug;80:31-5
15339226
Eur J Cell Biol. 2005 Mar;84(2-3):137-49
15819396
J Parasitol. 2007 Oct;93(5):1006-15
18163333
Bioinformatics. 2007 Apr 1;23(7):793-801
17332025
Comp Biochem Physiol B Biochem Mol Biol. 2002 Nov;133(3):317-24
12431399
Trends Plant Sci. 2003 Jul;8(7):321-9
12878016
J Eukaryot Microbiol. 2008 Nov-Dec;55(6):530-5
19120799