Complex expression patterns in parts of orangutan DNA that are important for the immune system

6 January 2016

BPRC - 1. Complex expression patterns in parts of orangutan DNA that are important for the immune system

The Major Histocompatibility Complex (MHC) is a highly complex system, which plays an important role in the recognition of pathogens. This system exhibits a high degree of variation in order to prevent elimination of an entire population by a single pathogen. A component of the MHC, the MHC class I, plays a central role in responses of the immune system against infections and cancer.

In different animal species the MHC class I consists of different numbers of building blocks, also known as genes. This may suggest that the system has adapted, during the evolution in the course of resisting and surviving a  spectrum of infections. BPRC researchers have characterized this system in orangutans.

To investigate this, frozen cell lines were used. With modern techniques, it is not only possible to study the DNA code, but also to investigate the level of expression of a functional protein. The BPRC researchers have applied these techniques to material of orangutans to characterize the MHC class I in this species.

They found that orangutans, compared to humans and other great apes, display diverse and complex expression patterns of the MHC class I. Some parts of the MHC class I that are present in human/great ape species, are lacking in some orangutans. However, the researchers revealed that orangutans have a different piece of DNA in the MHC class I that might be able to compensate this. Because it is expressed on the cell surface as a protein, this part may specifically play an important role in the activation of the immune system. This work was published in the Journal of Immunology (http://www.ncbi.nlm.nih.gov/pubmed/26685209).