Experimental Evidence That Prenatal and Postnatal Developmental Stress Affects the Adult Seminal Fluid Proteome in a Precocial Bird.

Seminal fluid proteins are important modulators of male fertility and reproductive success, yet little is known about how their abundance responds to early-life developmental stress. Japanese quail Coturnix japonica) males produce a unique seminal foam that enhances fertilisation success. We characterised the proteome of the seminal foam for the first time and assessed how its composition is influenced by prenatal and postnatal developmental stress. Proteomic identification using liquid chromatography-tandem mass spectrometry and subsequent gene ontology (GO) analysis of chicken (Gallus gallus domesticus) orthologs suggested roles for the foam proteome in sperm maturation and DNA protection, semen liquefaction, sperm plasma membrane homeostasis and energy production for sperm motility. Males that experienced prenatal stress exhibited increased abundance of proteins involved in lipid metabolic processes, inflammation and oxidative stress, including proteolytic enzymes, interleukin receptors and avidin-like proteins. Similarly, males that exhibited postnatal stress exhibited increased abundance of proteins involved in chromatin organisation, carbon metabolism and oxidative stress. Nine proteins involved in metabolic processes and antioxidant processes were consistently more abundant across developmentally stressed males from both experiments, suggesting convergent responses to early-life stress. These results demonstrate that early development environments can alter the seminal foam proteome of adult males, with potential implications for ejaculate quality and fertilisation ability.