Biology subjects

Reichenbach, Z.

Publications and source records attributed to Reichenbach, Z..

2 recordsLinked to original sources

bioRxiv2026

NIX-associated mitochondrial remodeling contributes to esophageal epithelial differentiation

Mitochondria are increasingly recognized as regulators of cellular differentiation, but their role in esophageal epithelial homeostasis remains poorly understood. Here, we investigated mitochondrial remodeling during esophageal epithelial differentiation and whether mitochondrial depletion contributes to the acquisition of the differentiated phenotype. Mitochondrial abundance was assessed across normal human esophageal epithelium and in non-transformed immortalized human esophageal epithelial cells (EPC2-hTERT) using two differentiation models. Mitochondrial architecture was quantified, and the functional role of mitochondrial abundance was examined using doxycycline-inducible depletion of transcription factor A, mitochondrial (TFAM). Mitochondrial abundance progressively decreased from basal to superficial compartments of normal human esophageal epithelium and during in vitro differentiation, accompanied by fragmentation and remodeling of the mitochondrial network. TFAM depletion reduced mitochondrial abundance and increased squamous differentiation markers, indicating that mitochondrial depletion was sufficient to promote differentiation. Analysis of candidate mitochondrial clearance pathways identified Bcl2-interacting protein 3-like (BNIP3L)/NIX (NIP3-like protein X) as preferentially associated with differentiated epithelial cells and induced during differentiation. NIX was associated with mitochondria and increased as mitochondrial abundance declined. NIX depletion prevented differentiation-associated mitochondrial depletion and attenuated differentiation marker induction. In human esophageal epithelium, NIX expression increased across the basal-to-suprabasal compartment before declining superficially. BNIP3L expression was reduced in active eosinophilic esophagitis (EoE) and increased following corticosteroid-associated remission. Interleukin-13 similarly reduced BNIP3L expression and suppressed epithelial differentiation in EPC2-hTERT cells. These findings identify NIX-associated mitochondrial remodeling as an important component of esophageal epithelial differentiation and suggest that disruption of mitochondrial quality control may contribute to impaired epithelial differentiation in EoE.

cell biology↗

bioRxiv2026

Biofilm-Derived Curli and Z-DNA Shape Anti-DNA Antibody Responses During Salmonella Infections

Antibodies to Z-DNA, a non-canonical DNA conformation with a left-handed zigzag backbone, are abundant in the serum of patients with systemic lupus erythematosus (SLE), with levels increasing with disease activity and flares. As SLE is associated with bacterial infections, and as extracellular DNA (eDNA) within biofilms of several bacterial species has been shown to adopt the Z-DNA conformation, bacterial Z-DNA may represent a source of immunogenic Z-DNA in SLE and other related autoimmune conditions. In these studies, we investigated whether eDNA in Salmonella biofilms also contained Z-DNA and whether such Z-DNA could elicit an antibody response. Using antibody-based staining approaches, we observed abundant eDNA in Salmonella enterica serovar Typhimurium (STm) biofilms in both the Z- and canonical B-DNA configurations, consistent with the highly Z-prone nature of the GC-rich Salmonella genome. To assess the functional contribution of these DNA conformations to biofilm integrity, biofilms were treated with DNase I, which lacks enzymatic activity against Z-DNA, or with benzonase, a nonspecific nuclease that degrades both B- and Z-DNA. DNase I treatment applied after biofilm maturation was less effective at thinning biofilms than treatment during early biofilm formation, a pattern also observed with benzonase treatment. Purified curli:DNA complexes contained Z-DNA and, when administered intraperitoneally to mice, elicited robust anti-Z-DNA antibody responses. Similarly, infection with invasive STm induced the production of anti-Z-DNA antibodies in vivo. Moreover, STm infection in mice fed a diet that promotes biofilm development was associated with increased Z-DNA levels in the cecal lumen and elevated anti-DNA antibody responses. Collectively, these findings suggest that Z-DNA, likely formed by extruded Salmonella genomic DNA, and embedded within curli:DNA complexes of STm biofilms, triggers a host immune response and drives anti-Z-DNA antibody production. This work provides mechanistic insight into how bacterial infections and diet-dependent modulation of biofilm formation may contribute to anti-Z-DNA antibody responses in autoimmune diseases like SLE.

immunology↗