Accelerated pseudogenization of trace amine-associated receptor genes in primates

Area of Science:

• Evolutionary biology
• Genomics
• Olfactory receptor research

Background:

• Trace amines (TAs) and their receptors (TAARs) are crucial for detecting odors, particularly carnivore scents.
• TAAR genes proliferated in terrestrial mammals, enabling adaptation to ground-dwelling and predator detection.
• Primate genomes exhibit a notably lower number of TAAR genes compared to other mammals.

Purpose of the Study:

• To investigate the evolutionary forces behind the reduced TAAR gene repertoire in primates.
• To analyze the pseudogenization process of TAAR genes across primate lineages.
• To understand the impact of arboreal life and morphological changes on TAAR evolution.

Main Methods:

• Exhaustive data mining of TAAR genes across 13 primate and 2 nonprimate euarchontan genomes.
• Identification and analysis of pseudogenes within primate TAAR repertoires.
• Comparative genomic analysis to trace evolutionary patterns.

Main Results:

• A significant number of TAAR pseudogenes were identified in primate genomes.
• The degeneration of TAARs correlates with arboreal lifestyles, reducing predator exposure.
• Changes in haplorhine nose shape accelerated TAAR pseudogenization after divergence from strepsirrhines.

Conclusions:

• The reduction in TAARs in primates is linked to a decreased reliance on olfactory predator detection due to arboreal adaptation.
• Evolutionary deterioration of TAARs was further influenced by changes in olfactory-related anatomy.
• Recent primate evolution shows evidence of selection pressure and functional diversification impacting TAAR subfamilies.