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Biology subjects

Chen, C. P.

Publications and source records attributed to Chen, C. P..

3 recordsLinked to original sources

Dynamic polyadenylation safeguards developmental trajectories during paused embryogenesis

Embryonic pausing, including forms of diapause, enables development to be reversibly suspended during adverse conditions, but how paused embryos preserve cell fate patterning remains unclear. Using zebrafish, we show that developmental pausing results in the temporary collapse of Wnt, BMP, FGF, and Nodal signaling gradients, despite broad preservation of cell identity at the transcriptional level. In parallel, pausing induces a dormancy-enriched gene expression program (DEEP), which includes the non-canonical poly(A) polymerase tent5ba. Tent5ba promotes survival through pausing, sustains DEEP expression, and is required for robust reestablishment of axial patterning upon developmental re-entry. Poly(A)-tail and transcriptional profiling further link tent5ba to the stabilization of mRNA targets associated with robust developmental outcomes, supporting a model in which transcript polyadenylation safeguards patterning fidelity through suspended embryogenesis.

developmental biology↗

Age-linked lung pathology is reduced by immunotherapeutic targeting of isoDGR protein damage

Advancing age is the primary risk factor for pulmonary diseases. Our investigation revealed an 8-fold increase in aging induced isoDGR-damaged proteins in lung tissue from human pulmonary fibrosis patients compared to healthy tissues, accompanied by elevated frequencies of CD68+/CD11b+ macrophages, indicating lung tissue is susceptible to time-dependent accumulation of isoDGR-proteins. To elucidate the mechanisms through which isoDGR-proteins may exacerbate aging lung disorders for potential therapeutic targeting, we assessed the functional role of this isoDGR-motif in naturally-aged mice and mice lacking the corresponding isoDGR repair enzyme (Pcmt1-/-). IsoDGR-protein accumulation in mouse lung tissue and blood vessels correlated with chronic low-grade inflammation, pulmonary edema, and hypoxemia. IsoDGR accretion induced mitochondrial and ribosomal dysfunctions, cellular senescence, and apoptosis, contributing to progressive lung damage over time. Treatment with anti-isoDGR antibodies suppressed TLR pathway activity, mitigated cytokine-driven inflammation, restored mtDNA expression, and significantly reduced lung pathology in-vivo. Similarly, exposure of lung endothelial cells to isoDGR-modified fibronectin impaired oxygen consumption, increased reactive oxygen species levels, and disrupted acidification, but these effects were efficiently reversed by target-specific antibody therapy. Collectively, our findings underscore the significant contribution of isoDGR-damaged proteins to age-linked lung pathology. IsoDGR-specific therapy emerges as a promising treatment approach for pulmonary disorders in older patients.

pathology↗

Antibody targeting of aging damaged isoDGR-protein doubles lifespan in a mouse model of chronic inflammation

Aging is the result of the accumulation of molecular damages that impair normal biochemical activities. We previously reported that aging-damaged amino acid sequence NGR (Asn-Gly-Arg) results in a gain-of-function conformational switching to isoDGR (isoAsp-Gly-Arg) motif. This integrin-binding motif activates leukocytes to induce chronic inflammation, which are characteristic features of age-linked cardiovascular disorders. We now report that anti-isoDGR immunotherapy doubles lifespan in mouse model of chronic inflammation. We observed extensive accumulation of isoDGR and inflammatory cytokine expression in multiple tissues from Pcmt1-KO and old WT animals, which could also be induced via injection of isoDGR-modified plasma proteins or synthetic peptides into young WT animals. However, weekly injection of anti-isoDGR mAb (1mg/kg) was sufficient to significantly reduce isoDGR-modified proteins and pro-inflammatory cytokine expression, improve behaviour and coordination, and double the average lifespan of Pcmt1-KO mice. Mechanistically, isoDGR-mAb mediated the immune clearance of damaged isoDGR-proteins by antibody-dependent cellular phagocytosis. These results indicate that immunotherapy targeting aging-damaged proteins may represent effective interventions for a range of age-linked degenerative disorders. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/532237v1_ufig1.gif" ALT="Figure 1"> View larger version (12K): org.highwire.dtl.DTLVardef@81610borg.highwire.dtl.DTLVardef@a22aaorg.highwire.dtl.DTLVardef@169fe50org.highwire.dtl.DTLVardef@1b73d11_HPS_FORMAT_FIGEXP M_FIG Anti-isoDGR immunotherapy induces immune clearance of aging damaged isoDGR-proteins to reduce chronic inflammation, improve behaviour and coordination, and double lifespan in PCMT-/- mice. C_FIG

biochemistry↗