Molecular Phylogenetic Analysis of the AIG Family in Vertebrates

Abstract

Androgen-inducible genes (AIGs), which can be regulated by androgen level, constitute a group of genes characterized by the presence of the AIG/FAR-17a domain in its protein sequence. Previous studies on AIGs demonstrated that one member of the gene family, AIG1, is involved in many biological processes in cancer cell lines and that ADTRP is associated with cardiovascular diseases. It has been shown that the numbers of AIG paralogs in humans, mice, and zebrafish are 2, 2, and 3, respectively, indicating possible gene duplication events during vertebrate evolution. Therefore, classifying subgroups of AIGs and identifying the homologs of each AIG member are important to characterize this novel gene family further. In this study, vertebrate AIGs were phylogenetically grouped into three major clades, ADTRP, AIG1, and AIG-L, with AIG-L also evident in an outgroup consisting of invertebrsate species. In this case, AIG-L, as the ancestral AIG, gave rise to ADTRP and AIG1 after two rounds of whole-genome duplications during vertebrate evolution. Then, the AIG family, which was exposed to purifying forces during evolution, lost or gained some of its members in some species. For example, in eutherians, Neognathae, and Percomorphaceae, AIG-L was lost; in contrast, Salmonidae and Cyprinidae acquired additional AIG copies. In conclusion, this study provides a comprehensive molecular phylogenetic analysis of vertebrate AIGs, which can be employed for future functional characterization of AIGs.

Genome of tropical bed bugCimex hemipterus(Cimicidae, Hemiptera) reveals tetraspanin expanded in bed bug ancestor

“…The difference was contributed by tandem gene duplicates in C. hemipterus , including a cluster of 9 FAR-17a/AIG1-like protein coding genes on chromosome 16 (Supplementary Figure 6A). Although all annotated FAR-17a/AIG1-like proteins were expressed in C. hemipterus (Supplementary Figure 6B), little is known about their function in insects as FAR-17a/AIG1-like proteins were mainly characterized in vertebrate models as an androgen-responsive gene and a role player in cancer-related processes (Huang et al 2021). On the other hand, in addition to known insect tetraspanin orthologous families (Huang et al 2005), the expansion in tetraspanin was contributed by a newly identified family termed “N-3”, which was also found in hemipteran Orius laevigatus (Supplementary Figure 7 and 8).…”

Developing a bioinformatics pipeline for comparative protein classification analysis

“…6 A ). To verify the syntenic relationships I only suggest to run a Multiple Sequence Alignments (MSA) scanning algorithm if necessary [ 79 , 80 ].…”