Multifunctional roles of the UDP-glycosyltransferase gene family in insects

UDP-glycosyltransferases (UGTs) are important conjugation enzymes found in all kingdoms of life, catalyzing a sugar conjugation with small lipophilic compounds and playing important roles in detoxification. It is also involved in pigment sequestration providing color to the cuticle, wings or cocoons in insects. Some UGTs are highly expressed in insect antennae, proposing a novel function in olfaction. Insect UGTs, therefore, show multifaceted roles in insect. UGTs have been identified in a number of insect genomes over the last decade and much progress has been achieved in characterizing their expression patterns and molecular functions. Here, we present an update of insect UGTs and their putative roles, including the Drosophila melanogaster UGT gene family. A total of 35 UGT genes are found in the D. melanogaster genome, localized to chromosomes 2 and 3 with a high degree of gene duplications on chromosome arm 3R. All D. melanogaster UGT genes have now been named following the unified nomenclature approved by the UGT nomenclature committee, thereby facilitating comparisons between species. Extended searches reveal that similar numbers of UGT genes are present in other Drosophila species, and comparative phylogenetic analyses suggest an overall high conservation as well as some species-specific gene duplications and losses. Research findings have included the demonstration of roles for specific Drosophila UGTs in detoxification, olfaction, and cold tolerance. Together, the updated genomic information and research overview provided herein will aid further research in this developing field.