DNA damage modulates interactions between microRNAs and the 26S proteasome.

26S proteasomes are known as major non-lysosomal cellular machines for coordinated and specific destruction of ubiquitinylated proteins. The proteolytic activities of proteasomes are controlled by various post-translational modifications in response to environmental cues, including DNA damage. Besides proteolysis, proteasomes also associate with RNA hydrolysis and splicing.

Peroxiredoxin V contributes to antioxidant defense of lung epithelial cells.

The aim of this study was to determine the functional significance of peroxiredoxin V (PRXV) in defense against oxidative stress and changes of its expression in human lung inflammation. We used in vitro cell cultures and retrospective analyses of human sputum samples to perform the study. We found that stable clones of lung epithelial cell lines A549 and U1810 with reduced expression of PRXV were prone to oxidative damage.

Migrating leukocytes are the source of peroxiredoxin V during inflammation in the airways.

Background: We characterized changes in expression of the antioxidant protein Peroxiredoxin V (PRXV) during airway inflammation.

Methods: Studies in anesthetized rats and mice; PRXV expression determined by Western blot analyses and immunohistochemistry; PRXV m-RNA expression determined by Taq-Man RT-PCR.

Results: Bacterial lung inflammation did not change expression of PRXV in murine epithelia but produced massive influx of leukocytes highly expressing PRXV.

Downregulation of peroxiredoxin V stimulates formation of etoposide-induced double-strand DNA breaks.

Antioxidant protein Peroxiredoxin V (PrxV) is located in mitochondria and peroxisomes but is also present in the nucleus. Here, we show that nuclear PrxV associates with coilin-containing bodies suggesting possible interaction of this protein with transcription complexes. We also studied etoposide-induced phosphorylation of histone H2AX (gamma-H2AX) in human cells in which PrxV activity was downregulated (knockdown, KD-clones) or compromised by overexpression of redox-negative (RD) protein.