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Biology subjects

Eibl, C.

Publications and source records attributed to Eibl, C..

2 recordsLinked to original sources

Alterations of redox and iron metabolism accompany development of HIV latency.

Metabolic alterations, such as oxidative stress, are hallmarks of HIV-1 infection. However, their influence on the development of viral latency, and thus on HIV-1 persistence during antiretroviral therapy (ART), have just begun to be explored. We analyzed omics profiles of in-vitro and in-vivo models of infection by HIV-1 and its simian homolog SIVmac. We found that cells survive retroviral replication by upregulating antioxidant pathways and intertwined iron import pathways. These changes are associated with remodeling of the redox sensitive promyelocytic leukemia protein nuclear bodies (PML NBs), an important constituent of nuclear architecture and a marker of HIV-1 latency. We found that PML is depleted in productively infected cells and restored by ART. Moreover, we identified intracellular iron as a key link between oxidative stress and PML depletion, thus supporting iron metabolism modulators as pharmacological tools to impair latency establishment.

molecular biology↗

Control Of AMPA Receptor Activity By The Extracellular Loops Of Auxiliary Proteins

At synapses throughout the mammalian brain, AMPA receptors form complexes with auxiliary proteins, including TARPs. However, how TARPs modulate AMPA receptor gating remains poorly understood. We built structural models of TARP-AMPA receptor complexes for TARPs {gamma}2 and {gamma}8, combining recent structural studies and de novo structure predictions. These models, combined with peptide binding assays, provide evidence for multiple interactions between GluA2 and variable extracellular loops of TARPs. Substitutions and deletions of these loops had surprisingly rich effects on the kinetics of glutamate-activated currents, without any effect on assembly. Critically, by altering the two interacting loops of {gamma}2 and {gamma}8, we could entirely remove all allosteric modulation of GluA2, without affecting formation of AMPA receptor-TARP complexes. Likewise, substitutions in the linker domains of GluA2 completely removed any effect of Y2 on receptor kinetics, indicating a dominant role for this previously overlooked site proximal to the AMPA receptor channel gate.

biophysics↗