DYRK4, a member of the dual-specificity tyrosine phosphorylation-regulated kinase family, has been implicated in multiple biological processes. It is involved in antiviral innate immunity, and may also play roles in cancer-related processes such as lung cancer and breast cancer development [1,2,3]. DYRK4 is a testis-specific kinase in mice, though it is dispensable for male fertility [4]. Different splice variants of DYRK4 have distinct sub-cellular localizations and catalytic activities [5].

In antiviral innate immunity, DYRK4 acts as a scaffold protein. Knockout or knockdown of DYRK4 in cells impairs virus-induced activation of IRF3 and NF-κB, while overexpression enhances virus-triggered activation of IRF3 and type I IFN induction. Dyrk4-knockout mice are more susceptible to viral infection, indicating its importance in antiviral responses [1]. In lung cancer, hypomethylation of DYRK4 in peripheral blood is associated with an increased risk of lung cancer, suggesting its potential as a biomarker [2]. In aggressive breast cancers, a novel chimeric transcript RAD51AP1-DYRK4 is preferentially expressed in luminal B tumors, which endows increased sensitivity to the MEK inhibitor trametinib [3].

In conclusion, DYRK4 is a multifunctional gene. Its role in antiviral innate immunity is crucial as demonstrated by knockout mouse models. In cancer, DYRK4 shows promise as a biomarker in lung cancer and is involved in the molecular pathobiology of aggressive breast cancers, providing potential new therapeutic opportunities. The study of DYRK4 through gene knockout models has enhanced our understanding of its functions in these disease-related areas.

References:

1. Zeng, Xianhuang, Xu, Jiaqi, Liu, Jiaqi, Guo, Mingxiong, Sun, Guihong. 2024. DYRK4 upregulates antiviral innate immunity by promoting IRF3 activation. In EMBO reports, 26, 690-719. doi:10.1038/s44319-024-00352-x. https://pubmed.ncbi.nlm.nih.gov/39702801/

2. Qiao, Rong, Zhu, Qiang, Di, Feifei, Han, Baohui, Yang, Rongxi. 2023. Hypomethylation of DYRK4 in peripheral blood is associated with increased lung cancer risk. In Molecular carcinogenesis, 62, 1745-1754. doi:10.1002/mc.23612. https://pubmed.ncbi.nlm.nih.gov/37530470/

3. Liu, Chia-Chia, Veeraraghavan, Jamunarani, Tan, Ying, Hu, Yiheng, Wang, Xiao-Song. 2020. A Novel Neoplastic Fusion Transcript, RAD51AP1-DYRK4, Confers Sensitivity to the MEK Inhibitor Trametinib in Aggressive Breast Cancers. In Clinical cancer research : an official journal of the American Association for Cancer Research, 27, 785-798. doi:10.1158/1078-0432.CCR-20-2769. https://pubmed.ncbi.nlm.nih.gov/33172895/

4. Sacher, F, Möller, C, Bone, W, Gottwald, U, Fritsch, M. 2007. The expression of the testis-specific Dyrk4 kinase is highly restricted to step 8 spermatids but is not required for male fertility in mice. In Molecular and cellular endocrinology, 267, 80-8. doi:. https://pubmed.ncbi.nlm.nih.gov/17292540/

5. Papadopoulos, Chrisovalantis, Arato, Krisztina, Lilienthal, Eva, Becker, Walter, de la Luna, Susana. 2010. Splice variants of the dual specificity tyrosine phosphorylation-regulated kinase 4 (DYRK4) differ in their subcellular localization and catalytic activity. In The Journal of biological chemistry, 286, 5494-505. doi:10.1074/jbc.M110.157909. https://pubmed.ncbi.nlm.nih.gov/21127067/