Leucine-aminopeptidase A (LAP-A) Encoding Gene in Apoidea: from Genomic Identification to Functional Insights Based on Gene Expression

Aminopeptidases are enzymes that cleave the N-terminal region of proteins and show structural conservation in prokaryotes and eukaryotes. We aimed to identify leucine-aminopeptidase A (LAP-A) orthologs in the genome of bee species with different levels of social organization, and to explore the putative roles of this enzyme based on gene expression data. We identified a single gene for LAP-A on chromosome 15 of Apis mellifera L. and predicted orthologs in genomes of 11 bee species. We found evidence of LAP-A expression in more than 50 bee species. In honeybee and other bees, LAP-A transcripts were expressed in diverse tissues, including: brains, fat bodies, ovaries, testicles, integuments, and glands, on different developmental stages that spanned from embryogenesis to adult life. Our findings on the transcriptional activity of LAP-A are consistent with previously published data on enzymatic activity of LAP-A in bees throughout the development in different tissues and in both sexes. The presence of LAP-A gene in the Apoidea genomes and its ubiquitous expression support housekeeping roles of this enzyme and broad-spectrum functions in bees, independent of their life styles.