FcεRIα, encoded by the FCER1A gene, is the α -subunit of the high-affinity receptor for the Fc portion of immunoglobulin E (IgE). It plays a central role in IgE-mediated allergic disorders, as well as in the immunity and immunopathology of some parasitic infections. It is specifically expressed on basophils and mast cells, and its expression is regulated in part by the IL-3-GATA-2 pathway during cell differentiation [1].

A study found that the natural antisense transcript (NAT) of FCER1A (FCER1A-AS) is co-expressed with the sense transcript (FCER1A-S). When FCER1A-AS is selectively knocked down in MC/9 cells using the CRISPR/RfxCas13d (CasRx) approach, the expression of both FCER1A-S mRNA and proteins is markedly decreased. Homozygous mice deficient in FCER1A-AS demonstrated a similar phenotype to FCER1A knockout mice in Schistosoma japonicum infection and in IgE-FcεRIα-mediated cutaneous anaphylaxis, indicating that FCER1A-AS is essential for maintaining FCER1A-S expression in mast cells and basophils [1].

In summary, FCER1A is crucial for IgE-dependent immune responses. The discovery of the role of FCER1A-AS in regulating FCER1A expression through in vivo studies using gene-deficient mouse models provides new insights into the mechanisms of IgE-mediated allergic diseases and anti-parasite immunity.

References:

1. Tang, Ruo-Yu, Yin, Lan, Yao, Liang, Zhang, Qing-Feng, Chen, Xiao-Ping. 2023. A Co-Expressed Natural Antisense RNA FCER1A-AS Controls IgE-Dependent Immunity by Promoting Expression of FcεRIα. In Microbiology spectrum, 11, e0073323. doi:10.1128/spectrum.00733-23. https://pubmed.ncbi.nlm.nih.gov/37154775/