A Protein-Based Biosensor for Detecting Calcium by Magnetic Resonance Imaging.

ABSTRACT: Calcium-responsive contrast agents for magnetic resonance imaging (MRI) offer a promising approach for noninvasive brain-wide monitoring of neural activity at any arbitrary depth. Current examples of MRI-based calcium probes involve synthetic molecules and nanoparticles, which cannot be used to examine calcium signaling in a genetically encoded form. Here, we describe a new MRI sensor for calcium, based entirely on a naturally occurring calcium-binding protein known as calprotectin. Calcium-binding causes calprotectin to sequester manganese ions, thereby limiting Mn²⁺ enhanced paramagnetic relaxation of nearby water molecules. We demonstrate that this mechanism allows calprotectin to alter T₁ and T₂ based MRI signals in response to biologically relevant cal

SUBMITTER: Ozbakir HF 

PROVIDER: S-EPMC9188784 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature