Genome-wide expression profiling of Drosophila adult heart organogenesis

ABSTRACT: The abstract of the manuscript titled "Signalling pathways involved in adult heart formation revealed by gene expression profiling in Drosophila" is given below: "Drosophila provides a powerful system for defining the complex genetic programs that drive organogenesis. Under control of the steroid hormone ecdysone, the adult heart in Drosophila forms during metamorphosis by a remodelling of the larval cardiac organ. Here, we evaluated the extent to which transcriptional signatures revealed by genomic approaches can provide new insights into the molecular pathways that underlie heart organogenesis. Whole-genome expression profiling at 8 successive time-points covering adult heart formation revealed a highly dynamic temporal map of gene expression through 13 transcript clusters with distinct expression kinetics. A functional atlas of the transcriptome profile strikingly points to the genomic transcriptional response of the ecdysone cascade, and a sharp regulation of key components belonging to a few evolutionary conserved signalling pathways. A reverse genetic analysis provided evidence that these specific signalling pathways are involved in discrete steps of adult heart formation. In particular, the Wnt signalling pathway is shown to participate in inflow tract and cardiomyocyte differentiation, while activation of the PDGF-VEGF pathway is required for cardiac valve formation. Thus, a detailed temporal map of gene expression can reveal signalling pathways responsible for specific developmental programs and provides here substantial grasp into heart formation." Keywords: Time-course analysis Total RNAs were prepared from dissected cardiac tubes of Drosophila staged pupae at 8 successive time-points 21, 24, 27, 30, 33, 36, 42 and 48 hours after puparium formation covering adult heart organogenesis. For each time-point sample, 5 cardiac tubes were hand dissected from staged individuals. Four independent biological replicates were analyzed to confer a high reproducibility and statistical significance of the expression data. PolyA+ RNAs were linearly amplified (32 amplifications), labelled (32 with Cy3 and 32 with Cy5), and used for hybridization on Drosophila high-density oligonucleotide (INDAC) dual-channel microarrays (32 arrays) according to a loop-design dedicated to time-course experiments. Given the same number of arrays (8), a simple loop design is more efficient than a reference design: direct comparisons, smallest variance for log ratios, balancing varieties with dye-swapping (including technical replicates) and no reference sample needed (which has no intrinsic interest in our study). A graphical representation of the loop design used on this study is showed in the associated manuscript.

ORGANISM(S): Drosophila melanogaster

SUBMITTER: Bruno ZEITOUNI 

PROVIDER: E-GEOD-7689 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress