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bioRxiv · 10.1101/2025.02.02.635915

AKAP12 variant 1 knockout enhances vascular endothelial cell motility

Ali, A.·Roy, B.·Schott, M.·Grove, B.
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Abstract

In this study, we examined the role of AKAP12, in endothelial cell motility, with a specific focus on AKAP12 variants AKAP12v1 and AKAP12v2. Previous work has shown that AKAP12, a multivalent A-kinase anchoring protein that binds to PKA and several other proteins regulating protein phosphorylation, is expressed at low levels in most endothelia in vivo but at higher levels in cells in vitro. Here, we found that AKAP12 expression in endothelial cell (HUVEC) cultures was cell density-dependent, with the expression being highest in subconfluent cultures and lowest in confluent cultures. AKAP12 expression was also elevated in cells at the wound edge of wounded endothelial cell monolayers. Knockdown of variants 1 and 2 inhibited cell migration, whereas CRISPR/Cas9 knockout of AKAP12v1 enhanced migration, indicating that the absence of this variant and the presence of AKAP12v2 may shift the signaling pathways. Further analysis using bulk RNA sequencing revealed that the loss of AKAP12v1 affects genes associated with cell migration and intercellular junctions. We propose that AKAP12v1 and AKAP12v2 work together to modulate endothelial cell migration, providing insights into their distinct yet complementary roles in endothelial function and potential implications for cardiovascular health.

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Ali, A., Roy, B., Schott, M., Grove, B.. 2025-02-03. AKAP12 variant 1 knockout enhances vascular endothelial cell motility. https://doi.org/10.1101/2025.02.02.635915

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