Pyrosequencing the transcriptome of the greenhouse whitefly, Trialeurodes vaporariorum reveals multiple transcripts encoding insecticide targets and detoxifying enzymes.
BACKGROUND
The whitefly Trialeurodes vaporariorum is an economically important crop pest in temperate regions that has developed resistance to most classes of insecticides. However, the molecular mechanisms underlying resistance have not been characterised and, to date, progress has been hampered by a lack of nucleotide sequence data for this species. Here, we use pyrosequencing on the Roche 454-FLX platform to produce a substantial and annotated EST dataset. This 'unigene set' will form a critical reference point for quantitation of over-expressed messages via digital transcriptomics.


RESULTS
Pyrosequencing produced around a million sequencing reads that assembled into 54,748 contigs, with an average length of 965 bp, representing a dramatic expansion of existing cDNA sequences available for T. vaporariorum (only 43 entries in GenBank at the time of this publication). BLAST searching of non-redundant databases returned 20,333 significant matches and those gene families potentially encoding gene products involved in insecticide resistance were manually curated and annotated. These include, enzymes potentially involved in the detoxification of xenobiotics and those encoding the targets of the major chemical classes of insecticides. A total of 57 P450s, 17 GSTs and 27 CCEs were identified along with 30 contigs encoding the target proteins of six different insecticide classes.


CONCLUSIONS
Here, we have developed new transcriptomic resources for T. vaporariorum. These include a substantial and annotated EST dataset that will serve the community studying this important crop pest and will elucidate further the molecular mechanisms underlying insecticide resistance.
Rothamsted Research, Harpenden, Hertfordshire, UK. nikolaos.karatolos@bbsrc.ac.uk
Nikos
N
Karatolos
Yannick
Y
Pauchet
Paul
P
Wilkinson
Ritika
R
Chauhan
Ian
I
Denholm
Kevin
K
Gorman
David R
DR
Nelson
Chris
C
Bass
Richard H
RH
ffrench-Constant
Martin S
MS
Williamson
D000818:Animals; D019295:Computational Biology; D020869:Gene Expression Profiling; D006430:Hemiptera / Q000187:drug effects / Q000235:genetics*; D019476:Insect Proteins / Q000235:genetics; D007305:Insecticide Resistance / Q000235:genetics; D007306:Insecticides / Q000494:pharmacology*; D010802:Phylogeny
D019476:Insect Proteins; D007306:Insecticides
Pest Manag Sci. 2010 Dec;66(12):1304-7
20799247
Hum Genomics. 2009 Oct;4(1):59-65
19951895
Insect Biochem Mol Biol. 2008 Oct;38(10):940-9
18721883
Insect Mol Biol. 2010 Feb;19 Suppl 1:147-63
20167025
Annu Rev Entomol. 2000;45:449-66
10761585
Insect Mol Biol. 2010 Feb;19(1):61-75
19909380
Insect Biochem Mol Biol. 2008 Jan;38(1):113-23
18070670
Annu Rev Genomics Hum Genet. 2009;10:135-51
19715439
Mol Biol Evol. 2007 Aug;24(8):1596-9
17488738
Nucleic Acids Res. 2004 Feb 18;32(3):e37
14973331
Insect Mol Biol. 2006 Oct;15(5):615-36
17069637
Int J Plant Genomics. 2008;2008:619832
18483572
Insect Mol Biol. 2010 Mar;19 Suppl 2:155-64
20482647
IUBMB Life. 2007 Mar;59(3):151-62
17487686
Nucleic Acids Res. 2005 Jul 1;33(Web Server issue):W677-80
15980561
BMC Genomics. 2006 Apr 11;7:79
16608516
Science. 2002 Oct 4;298(5591):179-81
12364796
Nature. 2006 Oct 26;443(7114):931-49
17073008
Science. 2002 Oct 4;298(5591):129-49
12364791
PLoS Genet. 2010 Jun 24;6(6):e1000999
20585623
BMC Genomics. 2010 Jun 24;11:400
20573269
Insect Biochem Mol Biol. 2009 May-Jun;39(5-6):403-13
19364528
Proc Natl Acad Sci U S A. 2005 Jun 14;102(24):8420-5
15937112
Insect Biochem Mol Biol. 2008 Jun;38(6):634-44
18510975
Science. 2000 Mar 24;287(5461):2185-95
10731132
Bioinformatics. 2006 Aug 15;22(16):2020-7
16787968
Pest Manag Sci. 2010 Nov;66(11):1186-90
20632380
PLoS Biol. 2010 Feb 23;8(2):e1000313
20186266
Nucleic Acids Res. 2008 Jan;36(Database issue):D582-7
17933781
BMC Bioinformatics. 2009 Dec 24;10:447
20034392