GlycoEggshell · Glycoprotein (Glyco+protein) of the biomineralized eggshell in birds

Bird eggshell is a remarkable specimen for proteins analysis in archaeology and palaeontology as it can be used to understand how biominerals form and how they survive into deep time and elucidate phylogeny of the extinct birds. Proteins are known to survive best in association with minerals and proteins can persist in >6 million years old eggshell. Protective shell of eggs serves a crucial role for birds terrestrial adaptation as eggshell provides physical barrier to protect embryo, prevents desiccation during embryonic development, allows gas diffusion and provide calcium source for embryonic bone development. Organic matrix of eggshells is mainly made up of glycoproteins (glycan (sugar) + protein). The glycan study in archaeology and palaeontology is scarce and the application of glycoproteomics and glycomics in ancient eggshells will be a milestone in science, opening a new avenue to analyse sugar. The glycoprotein role in eggshell remains elusive and the GlycoEggshell project intends to describe and investigate specific roles of glycosylation on eggshell proteins across birds and evolutionary time, using modern and sub-fossil samples. GlycoEggshell project has three research objectives: characterise the glycosylated proteins in eggshells, identify the compositions and structures of the glycosaminoglycan (GAG), and determine the GAG-protein interactions. The modern eggshell from diverse bird clades will be used for glycoproteomics analysis to assess the glycosylation status among birds. Glycomics approach will be used to identify the GAG structures and compositions across modern and sub-fossil eggshells while the novel cell-based glycosaminoglycan array developed by my supervisor team in Copenhagen Center for Glycomics will be used to elucidate the interactions of protein and GAG. GlycoEggshell project will enhance our understanding of the glycosylated proteins role in the formation of the eggshell, the fastest biogenic calcification process known in nature.