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Roe, J.-S.

Publications and source records attributed to Roe, J.-S..

3 recordsLinked to original sources

Targeting Noncanonical TEAD Axis to Overcome DNA Repair-Driven Chemoresistance

How transcription factors contribute to DNA damage repair (DDR) independent of canonical gene regulation remains poorly understood. Here, we show that DNA double-strand break (DSB) triggers a functional state transition in TEAD, disengaging it from YAP-dependent transcription and translocating it to DNA lesions as a chromatin-associated DDR factor. Upon genotoxic stress, TEAD is rapidly recruited to damaged chromatin through a biphasic mechanism involving early poly(ADP-ribose)-dependent recruitment followed by ATM-driven {gamma}H2AX-mediated retention. At DNA lesions, TEAD constrains chromatin over-relaxation, suppresses excessive end resection, and promotes non-homologous end joining (NHEJ) independent of its canonical function. Conserved residues within the TEA domain mediate this noncanonical chromatin engagement of TEAD and define a druggable N-terminal interface. Pharmacological targeting of this interface impaired TEAD-dependent DSB repair and sensitized tumors to chemotherapy. Together, these findings establish noncanonical TEAD as a critical DNA repair factor and a clinically actionable driver of chemoresistance, while providing a conceptual framework for understanding how broader families of transcription factors may be repurposed as targetable DNA damage regulators in cancer.

cancer biology↗

Mitochondrial thermogenesis regulates heat-shock response in the nucleus

Mitochondrial thermogenesis is a process in which heat is generated by mitochondrial respiration. In living organisms, the thermogenic mechanisms that maintain body temperature have been studied extensively in fat cells, with little knowledge on how mitochondrial heat may act beyond energy expenditure. Here, we highlighted exothermic oxygen reduction reaction ({Delta}Hf{degrees} = -285 kJ/mol) is the main source of the protonophore-induced mitochondrial thermogenesis and this heat was conducted to other cellular organelles, including the nuclei. As a result, mitochondrial heat that reached the nucleus initiated the classical heat shock response, including the formation of nuclear stress granules and localization of heat shock factor 1 to chromatin. Consequently, activated HSF1 increases gene expression associated with the response to thermal stress in mammalian cells. Our results illustrate heat generated within the cells as a potential source of mitochondrial-nucleus communication and expand our understanding of the biological functions of mitochondria in cell physiology.

cell biology↗

Partial in vivo reprogramming enables injury-free intestinal regeneration via autonomous Ptgs1 induction

Tissue regeneration after injury involves the dedifferentiation of somatic cells, a natural adaptive reprogramming process that leads to the emergence of injury-responsive cells with fetal-like characteristics in the intestinal epithelium. However, there is no direct evidence that adaptive reprogramming involves a shared molecular mechanism with direct cellular reprogramming. Here, we induced dedifferentiation of intestinal epithelial cells through forced partial reprogramming in vivo using "Yamanaka factors" (Oct4, Sox2, Klf4, and c-Myc: OSKM). The OSKM-induced dedifferentiation showed similar molecular features of intestinal regeneration, including a rapid transition from homeostatic cell types to injury-responsive-like cell types. These injury-responsive-like cells, sharing a gene signature of revival stem cells and atrophy-induced villus epithelial cells, actively assisted tissue regeneration following ionizing radiation-induced acute tissue damage. In contrast to normal intestinal regeneration, which involves epi-mesenchymal crosstalk through induction of Ptgs2 (encoding Cox2) upon injury, the OSKM expression promotes the autonomous production of prostaglandin E2 via epithelial Ptgs1 (encoding Cox1) expression. These results indicate that prostaglandin synthesis is a common mechanism for intestine epithelial regeneration but involves a different enzyme (Ptgs1 for Cox1) when partial reprogramming is directly applied to the intestinal epithelium.

cell biology↗