Multiple roles of the polycistronic genetarsaless/mille-pattes/polished-riceduring embryogenesis of the kissing bugRhodnius prolixus

Abstract

Genes encoding small open-reading frames (smORFs) have been characterized as essential players of developmental processes. The smORF tarsaless/millepattes/polished-rice has been thoroughly investigated in holometabolous insects, such as the fruit fly Drosophila melanogaster and the red flour beetle Tribolium castaneum, while its function in hemimetabolous insects remains unknown. Thus, we analyzed the function of the tal/pri/mlpt ortholog in a hemimetabolous insect, the kissing bug Rhodnius prolixus (Rp). First, sequence analysis shows that Rp-tal/pri/mlpt polycistronic mRNA encodes two small peptides (11 to 14 amino acids) containing a LDPTG motif. Interestingly, a new hemipteran-specific conserved peptide of approximately 80 amino acids was also identified by in silico analysis. In silico docking analysis supports the high-affinity binding of the small LDPTG peptides to the transcription factor Shavenbaby. Rptal/pri/mlpt in situ hybridization and knockdown via RNA interference showed a conserved role of Rp-tal/pri/mlpt during embryogenesis, with a major role in the regulation of thoracic versus abdominal segmentation, leg development and head formation. Altogether, our study shows that tal/pri/mlpt segmentation role is conserved in the common ancestor of Paraneoptera and suggests that polycistronic genes might generate order specific smORFs.

The smORF-containing genemille-pattesis required for moulting andTrypanosoma cruzimetacyclogenesis in the Chagas disease vectorRhodnius prolixus

“…mille-pattes (mlpt) was the first polycistronic gene containing smORFs identified in the beetle Tribolium castaneum [14]. mlpt and its homologs polished rice (pri) or tarsalless(tal) play major roles during the embryogenesis of beetles, fruit flies, wasps and bugs [15][16][17]. An important role of mlpt/pri/tal in the differentiation of epithelia such as trichomes, gut precursors and tarsus was also described [16,18,19].…”

“…Mechanistically, the conserved peptides of 10-13 amino acids encoded by the smORFs in the mlpt gene are involved in the control of N-terminal processing of the Shavenbaby transcription factor [19][20][21][22]. Recently, multiple roles of the single ortholog of mlpt in R. prolixus during embryogenesis and the emergence of a new hemiptera-specific peptide were described [17], although other functions of this gene in the kissing remain unknown.…”

“…4368814), following manufacturer's instructions. Primers sequences of the constitutive geneRp-eEF-1, Rp-mlpt and Rp-EcR have been previously described[17,25]. The Green Fluorescent Protein (GFP) cDNA sequence was used as a template for the synthesis of an…”