Comparing the use of alternative splicing between human and mouse immune cells

Mouse is the most common model organism in biology in general and in immunology in particular. The genomes of the human and the mouse share a lot of similarities and orthologous genes between the human and the mouse have been defined. However, orthology at the level of exons, transcripts and junctions is not well defined, and the use of alternative splicing events in similar cell types has not been compared between the species.

A mapping of one-to-one orthologous exons and junctions was done between human and mouse. Based on this mapping, the ratio of the use of orthologous alternative splicing events was compared between human and mouse immune cells.

Of the 5,756 human-mouse orthologous alternative splicing events, ~560 events are expressed in human and mouse immune cells. Interestingly, many of these events showed a marked difference in transcript usage between humans and mice.

Mapping alternative splicing events between humans and mice and analyzing differences in the usage ratios of these events in immune cells across both species enables us to identify species-specific changes in protein functionality.