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Histidine tracts in human transcription factors: insight into metal ion coordination ability.

ABSTRACT: Consecutive histidine repeats are chosen both by nature and by molecular biologists due to their high affinity towards metal ions. Screening of the human genome showed that transcription factors are extremely rich in His tracts. In this work, we examine two of such His-rich regions from forkhead box and MAFA proteins-MB3 (contains 18 His) and MB6 (with 21 His residues), focusing on the affinity and binding modes of Cu²⁺ and Zn²⁺ towards the two His-rich regions. In the case of Zn²⁺ species, the availability of imidazole nitrogen donors enhances metal complex stability. Interestingly, an opposite tendency is observed for Cu²⁺ complexes at above physiological pH, in which amide nitrogens participate in binding.

SUBMITTER: Hecel A

PROVIDER: S-EPMC5756558 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Histidine tracts in human transcription factors: insight into metal ion coordination ability.

Hecel Aleksandra A Wątły Joanna J Rowińska-Żyrek Magdalena M Świątek-Kozłowska Jolanta J Kozłowski Henryk H

Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry 20171207 1

Consecutive histidine repeats are chosen both by nature and by molecular biologists due to their high affinity towards metal ions. Screening of the human genome showed that transcription factors are extremely rich in His tracts. In this work, we examine two of such His-rich regions from forkhead box and MAFA proteins-MB3 (contains 18 His) and MB6 (with 21 His residues), focusing on the affinity and binding modes of Cu<sup>2+</sup> and Zn<sup>2+</sup> towards the two His-rich regions. In the case ...[more]

PMID: 29218639

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