Characterisation of l(3)tb as a novel tumour suppressor allele of DCP2 in Drosophila melanogaster

Mutants provide an excellent platform for the discovery and characterization of gene functions. The present communication is a pioneering treatise on a hitherto undescribed function of the gene coding for the mRNA decapping protein 2 (DCP2) in Drosophila melanogaster. DCP2, the gene coding for the mRNA decapping enzyme, has been studied in various model organisms in the light of maintenance of transcript abundance and stability but has never been implicated in tumourigenesis. Herein, we describe the mapping and characterization of a novel tumour suppressor allele of DCP2 (CG6169), which we named as lethal(3)tumorous brain [l(3)tb]. The homozygous mutant individuals show prolonged larval life, develop larval brain tumors and are lethal in the larval/pupal stages. The tumour is characterized by the presence of increased number of superficial neuroblasts, abnormal chromosomal condensation and causes overgrowth in the wing and the eye-antennal discs of the homozygous mutant larvae, all of which are rescued by the introduction of a functional copy of DCP2 in the mutant background, thereby establishing the causal role of the mutation and providing a genetic validation of the allelism. Our findings therefore ascribe a novel role of tumor suppression to DCP2 besides its cognate function of mRNA decapping and thereby identify it as a potential candidate for future research on tumorigenesis.