Distinct O-Acetylation Patterns of Serum Glycoproteins among Humans, Mice, and Rats

Area of Science:

• Glycomics
• Biochemistry
• Animal Models

Background:

• O-acetylation of sialic acids on glycoproteins is a key post-translational modification with diverse biological roles.
• Mice and rats are commonly used animal models in biomedical research, but their glycosylation profiles may differ.
• Sialic acid O-acetylation patterns in serum glycoproteins are not well-characterized across different species.

Purpose of the Study:

• To investigate and compare the sialic acid O-acetylation patterns of serum glycoproteins in humans, rats, and mice.
• To highlight the differences in glycosylation profiles that may influence the choice of animal models for biomedical studies.

Main Methods:

• Intact N-glycopeptide analysis was employed to characterize sialic acid types and O-acetylation.
• Quantification of sialic acid modifications (Neu5Ac, Neu5Gc) and O-acetylation levels was performed.
• Comparison of glycan structures, including hybrid, core-fucosylated, and antenna types, was conducted.

Main Results:

• Human sera contained Neu5Ac without O-acetylation.
• Rat sera predominantly featured Neu5Ac with significant O-acetylation (>60%), alongside hybrid glycans.
• Mouse sera primarily contained Neu5Gc with lower O-acetylation (12%), and higher proportions of core-fucosylated and multi-antenna glycans compared to rats.

Conclusions:

• Significant differences exist in serum glycoprotein sialic acid O-acetylation patterns between rats and mice.
• These distinct glycosylation profiles underscore the importance of considering species-specific glycan variations when selecting animal models for research.
• The findings enhance understanding of O-acetylated sialoglycan diversity and its implications in comparative biomedical studies.