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de The, H.

Publications and source records attributed to de The, H..

3 recordsLinked to original sources

ALS driven by mutant NEK1 aggregation is accelerated by Pml loss, but clinically reversed through pharmacologic induction of Pml-mediated degradation

Germinal mono-allelic loss-of-function mutations of NEK1 drive Amyotrophic Lateral Sclerosis (ALS) at variable penetrance, presumably through haploinsufficiency. Modeling the ALS-associated Arg812Ter mutation in mice revealed that the resulting truncated Nek1 (Nek1t) is aggregation-prone, particularly in alpha-motoneurons (MNs), and drives canonical ALS symptoms when bi-allelically expressed (Nek1t/t). Promyelocytic leukemia (Pml) ablation allows for ALS symptoms to occur even in heterozygote Nek1wt/t animals, mimicking the human situation. Pml precludes disease occurrence by promoting SUMO-facilitated degradation of Nek1t proteins through PML nuclear bodies (NBs). Conversely, Pml induction, achieved by activating the interferon pathway via poly(I:C) treatment, clears Nek1t aggregates in MNs, dramatically reducing ALS-associated symptoms and extending survival by 5 months. Our studies highlight the role of NEK1 aggregates in ALS pathogenesis and identifies activation of interferon pathways as a candidate therapeutic strategy that not only promotes Pml-triggered SUMOylation/degradation of toxic misfolded proteins in vivo, but also facilitates the clearance of protein aggregates, yielding dramatic clinical improvement. These observations validate PML as a relevant therapeutic target in neurodegenerative conditions associated with protein aggregation.

pathology↗

Zbtb14 regulates monocyte and macrophage development through inhibiting pu.1 expression in zebrafish

Macrophages and their precursor cells, monocytes, are the first line of defense of the body against foreign pathogens and tissue damage. Although the origins of macrophages are diverse, some common transcription factors (such as PU.1) are required to ensure proper development of monocytes/macrophages. Here we report that the deficiency of zbtb14, a transcription repressor gene belonging to ZBTB family, leads to an aberrant expansion of monocyte/macrophage population in zebrafish. Mechanistically, Zbtb14 functions as a negative regulator of pu.1, and SUMOylation on a conserved lysine is essential for the repression activity of Zbtb14. Moreover, a serine to phenylalanine mutation found in an acute myeloid leukemia (AML) patient could target ZBTB14 protein to autophagic degradation. Hence, ZBTB14 is a newly identified gene implicated in both normal and malignant myelopoiesis.

developmental biology↗

Unbiased in vivo exploration of nuclear bodies-enhanced sumoylation reveals that PML orchestrates embryonic stem cell fate

Membrane-less organelles are condensates formed by phase separation whose functions often remain enigmatic. Upon oxidative stress, PML scaffolds Nuclear Bodies (NBs) to regulate senescence or metabolic adaptation, but their role in pluripotency remains elusive. Here we establish that PML is required for basal SUMO2/3 conjugation in mESCs and oxidative stress-driven sumoylation in mESCs or in vivo. PML NBs create an oxidation-protective environment for UBC9-driven SUMO2/3 conjugation of PML partners, often followed by their poly-ubiquitination and degradation. Differential in vivo proteomics identified several members of the KAP1 complex as PML NB-dependent SUMO2-targets. The latter drives functional activation of this key epigenetic repressor. Accordingly, Pml-/- mESCs re-express transposable elements and display features of totipotent-like cells, a process further enforced by PML-controlled SUMO2-conjugation of DPPA2. Finally, PML is required for adaptive stress responses in mESCs. Collectively, PML orchestrates mESC fate through SUMO2-conjugation of key transcriptional or epigenetic regulators, raising new mechanistic hypotheses about PML roles in normal or cancer stem cells.

cell biology↗