Mucin proteins are highly glycosylated molecules critical for mucus generation, cellular signaling, and microbial interactions on epithelial surfaces. Functionally, mucins share proline-, serine-, and threonine-rich (PTS) repeats that serve as O-glycosylation sites. However, unlike several other homologous gene families, several mucin subfamilies have evolved independently. The mechanisms through which these mucins evolved remain mostly unknown. In this on-going study we did a genome-wide analysis to find how conserved mucins are in other mammalian species. We identified that the secretory calcium-binding phosphoprotein (SCPP) gene locus is a hotspot for de novo mucin evolution in mammals. Further bioinformatic analysis of this locus documented 27 hitherto undescribed mucins, highlighting 15 instances of independent mucin evolution. We confirmed the expression of a subset of these mucins in saliva using gel electrophoresis and subsequent mass-spectrometric analysis. We constructed a plausible model arguing that the secretory and proline-rich nature of proteins encoded by genes in the SCPP locus provides fodder for recurrent mucinization. Our results have broad implications for understanding the evolution of gene families coding for O-glycosylated secreted multiple-repeat-domain proteins.
Collectively, in a world where communication between medical doctors, scientists, and the general public is often inefficient, I aim to bridge this gap as a scientist in medical and evolutionary genetics and make it mutually understandable across fields. With current treatments being tailored to individuals in things like precision medicine and gene therapy, my hope is to one day generate basic research-based breakthroughs that may lead to foundational treatments.