Are clustered genes in the genomes of Arabidopsis and Drosophila regulated differently?

In the eukaryotic genome, genes with similar functions tend to co-localize in close proximity. Such gene clusters together with non-clustered genes constitute a chromatin domain which is a higher order regulatory unit. On a lower level co-expressed genes are regulated by differential activity of transcription factors (TF). We compared genome-wide distributions of TF in gene clusters in the genomes of Drosophila melanogaster and Arabidopsis thaliana. This revealed a significant excess of TF genes in gene clusters of the Arabidopsis genome, whereas in the genome of Drosophila distribution of TF in gene clusters did not differ from stochastic. We speculate that these alternatives could lead to different pathways of regulation of clustered genes in two species and to evolutionary-progressive changes in architecture of regulatory networks, governing the activity of clustered genes in the animal kingdom.

► The genomes of Arabidopsis and Drosophila.
► Clusters of functionally relative genes.
► Transcription factors (TF) in gene clusters.
► No TF in Drosophila clusters comparative to Arabidopsis clusters.
► It suggests different regulatory mechanisms of clustered genes.