Abstract
Background: While changes in chromosome number that result in aneuploidy are associated with phenotypic consequences such as Down syndrome and cancer, the molecular causes of specific phenotypes and genome-wide expression changes that occur in aneuploids are still being elucidated. Results: We employed a segmental aneuploid condition in maize to study phenotypic and gene expression changes associated with aneuploidy. Maize plants that are trisomic for 90% of the short arm of chromosome 5 and monosomic for a small distal portion of the short arm of chromosome 6 exhibited a phenotypic syndrome that includes reduced stature, tassel morphology changes and the presence of knots on the leaves. The knotted-like homeobox gene knox10, which is located on the short arm of chromosome 5, was shown to be ectopically expressed in developing leaves of the aneuploid plants. Expression profiling revealed that ∼40% of the expressed genes in the trisomic region exhibited the expected 1.5 fold increased transcript levels while the remaining 60% of genes did not show altered expression even with increased gene dosage. Conclusion: We found that the majority of genes with altered expression levels were located within the chromosomal regions affected by the segmental aneuploidy and exhibits dosage-dependent expression changes. A small number of genes exhibit higher levels of expression change not predicted by the dosage, or display altered expression even though they are not located in the aneuploid regions.
| Original language | English (US) |
|---|---|
| Article number | 7 |
| Journal | BMC Genomics |
| Volume | 9 |
| DOIs | |
| State | Published - Jan 10 2008 |
Bibliographical note
Funding Information:The authors gratefully acknowledge the assistance of Peter Hermanson in helping with plant growth, nucleic acid isolations, and validation PCRs. Shawn Kaeppler provided field space and invaluable feedback regarding this work. We are grateful to Sarah Hake and James Birchler who provided valuable feedback and suggestions regarding this project. We appreciate the suggestions of several anonymous reviewers whom have greatly strengthened this manuscript. This work was supported by the University of Minnesota Graduate School. The Minnesota Supercomputing Institute provided access to software packages used for data analysis.
