KCNN4 as a Genomic Determinant of Cytosolic Delivery by the Attenuated Cationic Lytic Peptide L17E

Masashi Kuriyama; Hisaaki Hirose; Yoshimasa Kawaguchi; Junya Michibata; Masashi Maekawa; Shiroh Futaki

doi:10.1016/j.ymthe.2024.12.050

KCNN4 as a Genomic Determinant of Cytosolic Delivery by the Attenuated Cationic Lytic Peptide L17E

Mol Ther. 2025 Jan 1:S1525-0016(24)00850-5. doi: 10.1016/j.ymthe.2024.12.050. Online ahead of print.

Authors

Masashi Kuriyama¹, Hisaaki Hirose², Yoshimasa Kawaguchi¹, Junya Michibata¹, Masashi Maekawa³, Shiroh Futaki²

Affiliations

¹ Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
² Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan. Electronic address: [email protected].
³ Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Minato-ku, Tokyo 105-8512, Japan.

PMID: 39748507
DOI: 10.1016/j.ymthe.2024.12.050

Abstract

The development of a cytosolic delivery strategy for biopharmaceuticals is one of the central issues in drug development. Knowledge of the mechanisms underlying these processes may also pave the way for the discovery of novel delivery systems. L17E is a an attenuated cationic amphiphilic lytic (ACAL) peptide developed by our research group that shows promise for cytosolic antibody delivery. In this study, given the high efficacy of L17E in cytosolic delivery, we investigated the mechanism of action of L17E in detail. L17E was found to achieve cytosolic delivery predominantly by transient disruption of the plasma membrane without the need for endocytosis. Importantly, the cell line selectivity studies of L17E revealed a strong correlation between the efficiency of L17E-mediated delivery and the expression level of KCNN4, the gene encoding the calcium-activated potassium channel KCa3.1. Genetic and pharmacological regulation of KCNN4 expression and KCa3.1 activity, respectively, correlate closely with the efficiency of L17E-mediated cytosolic delivery, suggesting the importance of membrane potential regulation by extracellular Ca²⁺ influx. Therefore, the activity of the L17E is relevant to the calcium-activated potassium channel.