The Ni(II)-Binding Activity of the Intrinsically Disordered Region of Human NDRG1, a Protein Involved in Cancer Development

Abstract

Nickel exposition is associated with tumors of the respiratory tract such as lung and nasal cancers, acting through still-uncharacterized mechanisms. Understanding the molecular basis of nickel-induced carcinogenesis requires unraveling the mode and the effects of Ni(II) binding to its intracellular targets. A possible Ni(II)-binding protein and a potential focus for cancer treatment is hNDRG1, a protein induced by Ni(II) through the hypoxia response pathway, whose expression correlates with higher cancer aggressiveness and resistance to chemotherapy in lung tissue. The protein sequence contains a unique C-terminal sequence of 83 residues (hNDRG1*C), featuring a three-times-repeated decapeptide, involved in metal binding, lipid interaction and post-translational phosphorylation. In the present work, the biochemical and biophysical characterization of unmodified hNDRG1*C was performed. Bioinformatic analysis assigned it to the family of the intrinsically disordered regions and the absence of secondary and tertiary structure was experimentally proven by circular dichroism and NMR. Isothermal titration calorimetry revealed the occurrence of a Ni(II)-binding event with micromolar affinity. Detailed information on the Ni(II)-binding site and on the residues involved was obtained in an extensive NMR study, revealing an octahedral paramagnetic metal coordination that does not cause any major change of the protein backbone, which is coherent with CD analysis. hNDRG1*C was found in a monomeric form by light-scattering experiments, while the full-length hNDRG1 monomer was found in equilibrium between the dimer and tetramer, both in solution and in human cell lines. The results are the first essential step for understanding the cellular function of hNDRG1*C at the molecular level, with potential future applications to clarify its role and the role of Ni(II) in cancer development.

Per Aspera ad Chaos: Vladimir Uversky’s Odyssey through the Strange World of Intrinsically Disordered Proteins

“…The collection of papers and reviews in this section embodies this philosophy to study IDPs. This appears as one of the most intense fields of study, with 6 scientific articles and one review [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ] ( Table 1 ).…”

Paramagnetic NMR to study iron sulfur proteins: 13C detected experiments illuminate the vicinity of the metal center

“…Within this frame, we considered the behaviour of two different paramagnetic metalloproteins: CISD3 and PioC, both containing iron-sulfur clusters. At variance with other metalloproteins, in which the electron relaxation is driven by the coordination number of the metal ion (Spronk et al 2018 ; Ravera et al 2021 ; Beniamino et al 2022 ; Trindade et al 2021b ), the electronic correlation times in iron-sulfur proteins are determined by the magnetic coupling among the iron ions. Therefore, different FeS clusters affect their protein environments at different extent (Blondin and Girerd 1990 ; Banci et al 2018 , 1990 ; close to the molecular mechanism understanding 2018 ; Bennett et al 2022 ; Azam et al 2020 ; Gervason et al 2019 ; Stegmaier et al 2019 ; Mulliez et al 1999 ; Trindade et al 2023 ).…”

Synthesis of NaAlSiO4 Hollow Microspheres as Absorbents for the Removal of Heavy Metal ions in Environmental Remediation

“…Ni(II) and Cd(II) are two of the most common heavy metal ions found in e uents from a wide range of industries [8][9][10][11], which have been identi ed as the most dangerous heavy metals. Both are nonbiodegradable and easily enriched in organisms and can cause various serious diseases, such as kidney damage, bone degeneration, hypertension, emphysema, nervous system damage, and even cancer [12,13]. In recent years, many effective methods for removing heavy metal ions have been developed, including chemical precipitation [14,15], ion exchange [16], adsorption [6], membrane ltration [3], oxidation-reduction [17], and biological and photocatalytic methods [18,19].…”