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Powell AM, Edwards NA, Hunter H, Kiser P, Watson AJ, Cumming RC, Betts DH. Deletion of p66Shc Dysregulates ERK and STAT3 Activity in Mouse Embryonic Stem Cells, Enhancing Their Naive-Like Self-Renewal in the Presence of Leukemia Inhibitory Factor. Stem Cells Dev 2023; 32:434-449. [PMID: 37183401 DOI: 10.1089/scd.2022.0283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
The ShcA adapter protein is necessary for early embryonic development. The role of ShcA in development is primarily attributed to its 52 and 46 kDa isoforms that transduce receptor tyrosine kinase signaling through the extracellular signal regulated kinase (ERK). During embryogenesis, ERK acts as the primary signaling effector, driving fate acquisition and germ layer specification. P66Shc, the largest of the ShcA isoforms, has been observed to antagonize ERK in several contexts; however, its role during embryonic development remains poorly understood. We hypothesized that p66Shc could act as a negative regulator of ERK activity during embryonic development, antagonizing early lineage commitment. To explore the role of p66Shc in stem cell self-renewal and differentiation, we created a p66Shc knockout murine embryonic stem cell (mESC) line. Deletion of p66Shc enhanced basal ERK activity, but surprisingly, instead of inducing mESC differentiation, loss of p66Shc enhanced the expression of core and naive pluripotency markers. Using pharmacologic inhibitors to interrogate potential signaling mechanisms, we discovered that p66Shc deletion permits the self-renewal of naive mESCs in the absence of conventional growth factors, by increasing their responsiveness to leukemia inhibitory factor (LIF). We discovered that loss of p66Shc enhanced not only increased ERK phosphorylation but also increased phosphorylation of Signal transducer and activator of transcription in mESCs, which may be acting to stabilize their naive-like identity, desensitizing them to ERK-mediated differentiation cues. These findings identify p66Shc as a regulator of both LIF-mediated ESC pluripotency and of signaling cascades that initiate postimplantation embryonic development and ESC commitment.
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Affiliation(s)
- Andrew M Powell
- Department of Biology, The University of Western Ontario, London, Canada
| | - Nicole A Edwards
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Hailey Hunter
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Patti Kiser
- Department of Pathology and Laboratory Medicine, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Andrew J Watson
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
- Department of Obstetrics and Gynaecology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
- Genetics and Development Division, The Children's Health Research Institute, Lawson Health Research Institute, London, Canada
| | - Robert C Cumming
- Department of Biology, The University of Western Ontario, London, Canada
- Genetics and Development Division, The Children's Health Research Institute, Lawson Health Research Institute, London, Canada
| | - Dean H Betts
- Department of Biology, The University of Western Ontario, London, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
- Department of Obstetrics and Gynaecology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
- Genetics and Development Division, The Children's Health Research Institute, Lawson Health Research Institute, London, Canada
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p66Shc-mediated hydrogen peroxide production impairs nephrogenesis causing reduction of number of glomeruli. Life Sci 2021; 279:119661. [PMID: 34087282 DOI: 10.1016/j.lfs.2021.119661] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 05/14/2021] [Accepted: 05/24/2021] [Indexed: 01/15/2023]
Abstract
AIMS Adaptor protein p66Shc, encoded by Shc1 gene, contributes to the pathogenesis of oxidative stress-related diseases. p66Shc ability to promote oxidative stress-related diseases requires phosphorylation of serine 36 residue (Ser36) and depends on translocation of p66Shc to the mitochondria. We tested the hypothesis that abnormal p66Shc-mediated reactive oxygen species (ROS) production could be critically involved in nephrons development during nephrogenesis. MAIN METHODS We have generated unique mutant rats (termed p66Shc-Del), which express endogenous p66Shc with a 9-amino acid deletion, and lack regulatory Ser36. H2O2 renal production was measured by enzymatic microelectrode biosensors. Nephron numbers in 3-5 weeks old p66Shc-Del rats were quantified using the acid maceration method. KEY FINDINGS p66Shc-Del rats, as wild type salt sensitive rats, display increased mean arterial blood pressure following chronic exposure to a high salt diet. In contrast to wild type rats, p66Shc-Del rats display increased H2O2 renal production and are characterized by a reduction in renal function. The number of glomeruli is significantly reduced in adult p66Shc-Del rats. SIGNIFICANCE Since low nephron number is an established risk factor for kidney disease and hypertension in humans and rodents, our data suggest that H2O2 renal production, caused by irregular signaling of p66Shc, could be critical in regulating nephrogenesis and that abnormal p66Shc signaling negatively impacts kidney development and renal function by increasing susceptibility to diabetic nephropathy and hypertension-induced nephropathy.
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