Jdp2-deficient granule cell progenitors in the cerebellum are resistant to ROS-mediated apoptosis through xCT/Slc7a11 activation

Chia-Chen Ku,Ying-Chu Lin,Kohsuke Kato,Richard Eckner,Kazunari K Yokoyama,Deng-Chyang Wu,Che-Jung Kuo,Yukio Nakamura,Michiya Noguchi,Kenly Wuputra,Shigeo Saito,Kyosuke Nagata,Kan-Hung Lee,Chang-Shen Lin,Shih-Chieh Tsai,Hiroyuki Miyoshi,Jia-Bin Pan,Yan-Liang Lee,Wen-Hsin Lin

doi:10.1038/s41598-020-61692-x

Abstract

The Jun dimerization protein 2 (Jdp2) is expressed predominantly in granule cell progenitors (GCPs) in the cerebellum, as was shown in Jdp2-promoter-Cre transgenic mice. Cerebellum of Jdp2-knockout (KO) mice contains lower number of Atoh-1 positive GCPs than WT. Primary cultures of GCPs from Jdp2-KO mice at postnatal day 5 were more resistant to apoptosis than GCPs from wild-type mice. In Jdp2-KO GCPs, the levels of both the glutamate‒cystine exchanger Sc7a11 and glutathione were increased; by contrast, the activity of reactive oxygen species (ROS) was decreased; these changes confer resistance to ROS-mediated apoptosis. In the absence of Jdp2, a complex of the cyclin-dependent kinase inhibitor 1 (p21Cip1) and Nrf2 bound to antioxidant response elements of the Slc7a11 promoter and provide redox control to block ROS-mediated apoptosis. These findings suggest that an interplay between Jdp2, Nrf2, and p21Cip1 regulates the GCP apoptosis, which is one of critical events for normal development of the cerebellum.

Highlights

The Jun dimerization protein 2 (Jdp2) is expressed predominantly in granule cell progenitors (GCPs) in the cerebellum, as was shown in Jdp2-promoter-Cre transgenic mice
Sibling breeding of double-transgenic mice of the Jpd[2] promoter-Cre/ZEG or Jdp[2] promoter-Cre/ROSA26R strains was confirmed by LacZ (β-Gal) staining, green fluorescent protein (GFP) signal detection, and polymerase chain reaction (PCR) genotyping
Atoh-1-stained cells were quantified according to the calculation presented in Materials and Methods. *p < 0.05. (d) Western blot analysis showed that the expression of Atoh-1 was about 87% lower in GCPs from Jdp2-KO mice than in those from WT mice

Summary

Introduction

The Jun dimerization protein 2 (Jdp2) is expressed predominantly in granule cell progenitors (GCPs) in the cerebellum, as was shown in Jdp2-promoter-Cre transgenic mice. In the absence of Jdp[2], a complex of the cyclin-dependent kinase inhibitor 1 (p21Cip1) and Nrf[2] bound to antioxidant response elements of the Slc7a11 promoter and provide redox control to block ROS-mediated apoptosis. These findings suggest that an interplay between Jdp[2], Nrf[2], and p21Cip[1] regulates the GCP apoptosis, which is one of critical events for normal development of the cerebellum. Inhibition of Slc7a11 leads to intracellular cysteine depletion and increases ROS levels, which activate non-apoptotic forms of cell death such as ferroptosis[18]. The level of GSH during cerebellar development is still debated

Methods

Results

Conclusion