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bioRxiv · 10.64898/2026.03.10.710832

Trans-acting Determinants of Gene Expression: Effects of Transcription Factor Affinity, Abundance, and Localization

Lopez-Malo, M.·Maerkl, S. J.
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Abstract

Transcription factors (TFs) regulate gene expression by binding cis-regulatory DNA elements, yet how trans-regulatory characteristics such as TF affinity, concentration, and localization interact with cis-regulatory elements remains largely unclear. We systematically analyzed TF affinity mutants across abundance, and localization states and found that promoter binding-site strength most readily modulated expression levels, followed by TF localization and concentration, while affinity variations were mainly buffered. We further uncover performance trade-offs between TF abundance, localization, and affinity. Together, these results reveal how trans and cis factors collectively shape gene-regulatory output.

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Lopez-Malo, M., Maerkl, S. J.. 2026-03-11. Trans-acting Determinants of Gene Expression: Effects of Transcription Factor Affinity, Abundance, and Localization. https://doi.org/10.64898/2026.03.10.710832

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