Zinc finger protein Helios (Helios (IKZF2))

Zinc finger protein Helios, encoded by the IKZF2 gene, is a member of the Ikaros family of transcription factors, which directs gene expression in hematopoietic cells and is crucial for lymphoid and T cell development[5][6]. Like other Ikaros family members, Helios contains 4 N-terminal zinc finger domains for DNA binding and C-terminal zinc fingers necessary for dimerization and interactions with other proteins[5][6]. Helios forms homo- and heterodimers with other family members, participating in the regulation of immune responses and the establishment and maintenance of regulatory T cells (Tregs)[5]. Alterations or defects in Helios can disrupt lymphocyte development and function, contributing to disease states ranging from immune deficiencies to cancers such as leukemia and lymphoma[4][5][6][7]. Helios is used as a biomarker to distinguish thymic-derived Tregs from peripherally induced Tregs and plays a key role in immune system homeostasis. While drugs such as lenalidomide and pomalidomide target related family members via the cereblon E3 ubiquitin ligase for degradation, specific targeting of Helios is much less defined but is considered likely due to its structural and functional similarity within the family[4].

Other names

HeliosIKZF2IKAROS family zinc finger protein 2Zinc finger protein IKZF2

Targeted degradation via cereblon E3 ubiquitin ligase complex (established for other Ikaros family members, especially Ikaros (IKZF1) and Aiolos (IKZF3); inferred possible for Helios due to family similarity)