eur j biol European Journal of Biology 2602-2575 2618-6144 Istanbul University 10.26650/EurJBiol.2026.1756794 Signal Transduction Sinyal İletimi Ion Channels and Regulatory Signals of Heme https://orcid.org/0009-0002-8486-5695 Yusifov Taleh Ministry of Science and Education of the Republic of Azerbaijan https://orcid.org/0009-0005-2826-0335 Aliyeva Aysel Ministry of Science and Education of the Republic of Azerbaijan https://orcid.org/0009-0005-9597-5066 Gudratova Fidan Ministry of Science and Education of the Republic of Azerbaijan https://orcid.org/0009-0002-2416-3018 Aliyeva Nermin Ministry of Science and Education of the Republic of Azerbaijan 02 26 2026 85 1 57 65 08 02 2025 12 23 2025 Copyright © 1940, European Journal of Biology 1940 European Journal of Biology

Heme is vital for life and an indispensable factor in various physiological processes. Beyond its function as a key ligand, heme serves as a multifaceted biomodulator, actively regulating diverse protein functions and cellular pathways. One of its significant functions is modulating the activity of ion channels. Heme's regulation of cellular excitability is linked to vital physiological functions, including sensitivity to oxygen and blood pressure regulation through neural signals. Furthermore, heme's impact on ion channels' role in controlling vascular processes, such as strokes or bleeding. Given the functional importance of the heme-driven action of the ion channel, further exploration is warranted, as many aspects of this process remain understudied. This brief review aims to summarize the structural organization of heme-sensitive sites within ion channels and examines the functional consequences of heme action. We think this knowledge will enhance our understanding of heme-driven modulation in ion channels.

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