The ly49 gene family. A brief guide to the nomenclature, genetics, and role in intracellular infection

Abstract

Understanding the Ly49 gene family can be challenging in terms of nomenclature and genetic organization. The Ly49 gene family has two major gene nomenclature systems, Ly49 and Killer Cell Lectin-like Receptor subfamily A (klra). Mice from different strains have varying numbers of these genes with strain specific allelic variants, duplications, deletions, and pseudogene sequences. Some members activate NK lymphocytes, invariant NKT (iNKT) lymphocytes and γδ T lymphocytes while others inhibit killing activity. One family member, Ly49Q, is expressed only on myeloid cells and is not found on NK, iNKT, or γδ T cells. There is growing evidence that these receptors may regulate not just the immune response to viruses, but other intracellular pathogens as well. Thus, this review's primary goal is to provide a guide for researchers first encountering the Ly49 gene family and a foundation for future studies on the role that these gene products play in the immune response, particularly the response to intracellular viral and bacterial pathogens.

Keywords: Ly49; klra; myeloid cells; natural killer lymphocytes.

Figure 1

Genomic Organization in the four known mouse strains. Color coded to match Table 3 and Belanger et al. (2008). Uppercase gene is known to be expressed. Pseudogenes indicated with a psi symbol. Underlined sections indicate regions common in 129 and NOD mice that have also undergone duplication in NOD mice (Belanger et al., 2008).