Ankib1, ankyrin repeat and IBR domain containing 1, is an E3 ligase. It plays a role in regulating immune responses, especially in the retinoic acid-inducible gene-I-like receptor (RLR) signaling pathway. By binding to mitochondrial antiviral signaling proteins (MAVS), ANKIB1 promotes K48-linked polyubiquitination with K311R, leading to MAVS proteasomal degradation and attenuation of antiviral immune responses [1].

ANKIB1 deficiency in vivo significantly increases RLR-mediated production of type I interferon (IFN) along with pro-inflammatory factors, enhancing antiviral immunity and decreasing viral replication [1]. In addition, circular RNA_ANKIB1 has been found to be involved in multiple disease processes. For example, in osteosarcoma, it accelerates chemo-resistance by binding microRNA-26b-5p and modulating enhancer of zeste homolog 2 [2]. It also promotes osteosarcoma cell growth and invasion by stabilizing the regulation of miR-19b on the SOCS3/STAT3 pathway [3]. In cardiomyocytes, circANKIB1 alleviates hypoxia-induced injury by modulating the miR-452-5p/SLC7A11 axis [4].

In conclusion, Ankib1 and its circular RNA form play crucial roles in immune regulation and disease development, especially in viral infections and certain cancers. The study of Ankib1 knockout or conditional knockout models has provided valuable insights into its functions in these biological processes and disease conditions, offering potential therapeutic targets for related diseases.

References:

1. Liu, Wei, Yuan, Cui, Fu, Buwen, Ma, Zhenling, Jiao, Pengtao. 2024. E3 ubiquitin ligase ANKIB1 attenuates antiviral immune responses by promoting K48-linked polyubiquitination of MAVS. In Cell reports, 43, 114687. doi:10.1016/j.celrep.2024.114687. https://pubmed.ncbi.nlm.nih.gov/39213157/

2. Tang, JinShan, Duan, Gang, Wang, YunQing, Li, WenBo, Zhu, ZiQiang. . Circular RNA_ANKIB1 accelerates chemo-resistance of osteosarcoma via binding microRNA-26b-5p and modulating enhancer of zeste homolog 2. In Bioengineered, 13, 7351-7366. doi:10.1080/21655979.2022.2037869. https://pubmed.ncbi.nlm.nih.gov/35264070/

3. Du, Yi-Xin, Guo, Lin-Xin, Pan, Han-Song, Liang, Yi-Min, Li, Xiang. 2019. Circ_ANKIB1 stabilizes the regulation of miR-19b on SOCS3/STAT3 pathway to promote osteosarcoma cell growth and invasion. In Human cell, 33, 252-260. doi:10.1007/s13577-019-00298-6. https://pubmed.ncbi.nlm.nih.gov/31667786/

4. Li, Gang, Tang, Xiaolei, Tang, Huaping. . Circular RNA ANKIB1 alleviates hypoxia-induced cardiomyocyte injury by modulating miR-452-5p/SLC7A11 axis. In Advances in clinical and experimental medicine : official organ Wroclaw Medical University, 33, 261-272. doi:10.17219/acem/168242. https://pubmed.ncbi.nlm.nih.gov/37549012/