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Carrion-Vazquez, M.

Publications and source records attributed to Carrion-Vazquez, M..

2 recordsLinked to original sources

An Anti-amyloidogenic treatment to specifically block the consolidation of traumatic events in mouse

Post-traumatic stress disorder (PTSD) is a mental health disorder triggered by the exposure to a traumatic event that manifests with anguish, intrusive memories and negative mood changes. So far, there is no efficient treatment for PTSD other than symptomatic palliative care. Based on the implication of the functional amyloid cytoplasmic polyadenylation element binding protein-3 (CPEB3) in the consolidation of memory, we propose its active amyloid state as a possible therapeutic target by blocking the consolidation of traumatic memories through polyglutamine binding peptide 1 (QBP1), an inhibitor of the amyloid oligomerization previously investigated in Drosophila. To test this idea in mammals, here we have developed a transgenic mouse that constitutively expresses QBP1 peptide. We first assessed the innocuousness of this peptide for the normal development of the animal, which also showed normal locomotor activity and anxiety. By performing a battery of standard memory paradigms, we then showed that hippocampal-dependent and aversive memories were impaired in the QBP1 mice. Furthermore, protein expression in the hippocampi of experienced mice showed that QBP1 mice do not increase their levels of amyloid oligomerization, evincing the blockade of the CPEB3 protein in its inactive state. The ability of QBP1 to block aversive memories in mice represents the proof of concept of a novel pharmacological approach for prophylaxis and therapy of acute stress and post-traumatic stress disorders.

animal behavior and cognition

smFRET Detects Dual Binding Modes Modulated by Proline Isomerization in a Mega-Dalton Multi-Enzyme Complex

Cellulose is the most abundant organic molecule on Earth and represents a renewable and practically everlasting feedstock for the production of biofuels and chemicals. Self-assembled owing to the high-affinity cohesin-dockerin interaction, cellulosomes are huge multi-enzyme complexes with unmatched efficiency in the degradation of recalcitrant lignocellulosic substrates. The recruitment of diverse dockerin-borne enzymes into a multicohesin protein scaffold dictates the three-dimensional layout of the complex, and interestingly two alternative binding modes have been proposed. Using single-molecule Fluorescence Resonance Energy Transfer, molecular dynamics simulations and NMR measurements on a range of cohesin-dockerin pairs, we directly detect varying distributions between these binding modes that follow a built-in cohesin-dockerin code. Surprisingly, we uncover a prolyl isomerase-modulated allosteric control mechanism, mediated by the isomerization state of a single proline residue, which regulates the distribution and kinetics of binding modes. Overall, our data provide a novel mechanistic understanding of the structural plasticity and dynamics of cellulosomes.Competing Interest StatementThe authors have declared no competing interest.View Full Text

biophysics