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Murine serpin 2A is a redox-sensitive intracellular protein.

ABSTRACT: Murine serpin 2A is expressed at high levels in haemopoietic progenitors and down-regulated on differentiation. When it is constitutively expressed in the multipotent haemopoietic cell line, FDCP-Mix, it causes a delay in differentiation and increased clonogenic potential. The serpin is also dramatically up-regulated on T-cell activation. It has an unusual reactive site Cys-Cys sequence, a unique C-terminal extension and lacks a typical cleavable N-terminal signal sequence. In spite of these features, the protein is not a member of the ovalbumin-serpin family, but is instead most closely related to human antichymotrypsin. We have shown that the serpin is intracellular with prominent nuclear localization. Transverse urea gradient gels and CD studies show that the protein undergoes the stressed-relaxed conformational change typical of inhibitory serpins. However, we have not detected complex-forming activity with a set of proteases. Thermal denaturation studies also show that the protein has decreased structural stability under reducing conditions, although it lacks disulphide bonds within the core of the molecule. Our results show that serpin 2A is an intracellular protein with the potential to mediate its biological effects via interaction with non-protease intracellular targets. Furthermore, the results presented suggest a model whereby the serpin interactions could be modulated by redox conditions or conformational change induced by cleavage of the reactive-site loop.

SUBMITTER: Morris EC

PROVIDER: S-EPMC1223254 | biostudies-other | 2003 Apr

REPOSITORIES: biostudies-other

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Bomapin is a redox-sensitive nuclear serpin that affects responsiveness of myeloid progenitor cells to growth environment.

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The redox-sensitive transcription factor, Nrf2, regulates murine hematopoietic stem cell survival

2011-10-22 | GSE33139 | GEO

The redox-sensitive transcription factor, Nrf2, regulates murine hematopoietic stem cell survival

Project description:To better understand the differentiation and survival defect of Nrf2-/- HSPC, we performed gene expression studies on KSL cells isolated by FACS from Nrf2+/+ and Nrf2-/- mice. Gene expression data suggests that loss of Nrf2 leads to global defects in cytokine signaling, and the administration of the exogenous granulocyte colony-stimulating factor (G-CSF) improved HSPC survival despite increasing intracellular ROS. Bone marrow cells from young healthy Nrf2+/+ and Nrf2-/- mice (n=5 per genotype ) were pooled, stained with KSL cell marker and FACS. Total RNA was isolated from the pooled KSL cells, quantified, amplified and profiled. One pooled RNA sample from each genotype (Nrf2+/+ and Nrf2-/-) was profiled using Affymetrix GeneChip Mouse Gene ST 1.0 chips.

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