Divergent evolution of arrested development in the dauer stage of Caenorhabditis elegans and the infective stage of Heterodera glycines.
BACKGROUND
The soybean cyst nematode Heterodera glycines is the most important parasite in soybean production worldwide. A comprehensive analysis of large-scale gene expression changes throughout the development of plant-parasitic nematodes has been lacking to date.


RESULTS
We report an extensive genomic analysis of H. glycines, beginning with the generation of 20,100 expressed sequence tags (ESTs). In-depth analysis of these ESTs plus approximately 1,900 previously published sequences predicted 6,860 unique H. glycines genes and allowed a classification by function using InterProScan. Expression profiling of all 6,860 genes throughout the H. glycines life cycle was undertaken using the Affymetrix Soybean Genome Array GeneChip. Our data sets and results represent a comprehensive resource for molecular studies of H. glycines. Demonstrating the power of this resource, we were able to address whether arrested development in the Caenorhabditis elegans dauer larva and the H. glycines infective second-stage juvenile (J2) exhibits shared gene expression profiles. We determined that the gene expression profiles associated with the C. elegans dauer pathway are not uniformly conserved in H. glycines and that the expression profiles of genes for metabolic enzymes of C. elegans dauer larvae and H. glycines infective J2 are dissimilar.


CONCLUSIONS
Our results indicate that hallmark gene expression patterns and metabolism features are not shared in the developmentally arrested life stages of C. elegans and H. glycines, suggesting that developmental arrest in these two nematode species has undergone more divergent evolution than previously thought and pointing to the need for detailed genomic analyses of individual parasite species.
Elling
Axel A
AA
Interdepartmental Genetics Program, Iowa State University, Ames, IA 50011, USA. elling@iastate.edu
Mitreva
Makedonka
M
Recknor
Justin
J
Gai
Xiaowu
X
Martin
John
J
Maier
Thomas R
TR
McDermott
Jeffrey P
JP
Hewezi
Tarek
T
McK Bird
David
D
Davis
Eric L
EL
Hussey
Richard S
RS
Nettleton
Dan
D
McCarter
James P
JP
Baum
Thomas J
TJ
D000818:Animals; D017173:Caenorhabditis elegans / Q000378:metabolism*; D019295:Computational Biology; D020224:Expressed Sequence Tags; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D007814:Larva / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013025:Glycine max / Q000469:parasitology*; D013045:Species Specificity; D014431:Tylenchoidea / Q000378:metabolism*