Differential gene expression in mouse spermatogonial stem cells and embryonic stem cells
INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE
Authors: Bai, Yinshan; Feng, Meiying; Liu, Shanshan; Wei, Hengxi; Li, Li; Zhang, Xianwei; Shen, Chao; Zhang, Shouquan; Ma, Ningfang
Abstract
Mouse spermatogonial stem cells (mSSCs) may be reprogrammed to become pluripotent stem cells under in vitro culture conditions, due to epigenetic modifications, which are closely associated with the expression of transcription factors and epigenetic factors. Thus, this study was conducted to compare the gene expression of transcription factors and epigenetic factors in mSSCs and mouse embryonic stem cells (mESCs). Firstly, the freshly isolated mSSCs [mSSCs (f)] were enriched by magnetic-activated cell sorting with Thy1.2 (CD90.2) microbeads, and the typical morphological characteristics were maintained under in vitro culture conditions for over 5 months to form long-term propagated mSSCs [mSSCs (l)]. These mSSCs (l) expressed pluripotency-associated genes and were induced to differentiate into sperm. Our findings indicated that the mSSCs (l) expressed high levels of the transcription factors, Lin28 and Prmt5, and the epigenetic factors, Tet3, Parp1, Max, Tert and Trf1, in comparison with the mESCs, with the levels of Prmt5, Tet3, Parp1 and Tert significantly higher than those in the mESCs. There was no significant difference in Kdm2b expression between mSSCs (l) and mESCs. Furthermore, the gene expression of N-Myc, Dppa2, Tbx3, Nr5a2, Prmt5, Tet3, Parp1, Max, Tert and Trf1 in the mSSCs (l) was markedly higher in comparison to that in the mSSCs (f). Collectively, our results suggest that the mSSCs and the mESCs displayed differential gene expression profiles, and the mSSCs possessed the potential to acquire pluripotency based on the high expression of transcription factors and epigenetic factors. These data may provide novel insights into the reprogramming mechanism of mSSCs.
Quantitative Single-Cell Transcript Assessment of Biomarkers Supports Cellular Heterogeneity in the Bovine IVD
VETERINARY SCIENCES
Authors: Li, Kangning; Kapper, Devin; Mondal, Sumona; Lufkin, Thomas; Kraus, Petra
Abstract
Severe and chronic low back pain is often associated with intervertebral disc (IVD) degeneration. While imposing a considerable socio-economic burden worldwide, IVD degeneration is also severely impacting on the quality of life of affected individuals. Cell-based regenerative medicine approaches have moved into clinical trials, yet IVD cell identities in the mature disc remain to be fully elucidated and tissue heterogeneity exists, requiring a better characterization of IVD cells. The bovine coccygeal IVD is an accepted research model to study IVD mechano-biology and disc homeostasis. Recently, we identified novel IVD biomarkers in the outer annulus fibrosus (AF) and nucleus pulposus (NP) of the mature bovine coccygeal IVD through RNA in situ hybridization (AP-RISH) and z-proportion test. Here we follow up on Lam1, Thy1, Gli1, Gli3, Noto, Ptprc, Scx, Sox2 and Zscan10 with fluorescent RNA in situ hybridization (FL-RISH) and confocal microscopy. This permits sub-cellular transcript localization and the addition of quantitative single-cell derived values of mRNA expression levels to our previous analysis. Lastly, we used a Gaussian mixture modeling approach for the exploratory analysis of IVD cells. This work complements our earlier cell population proportion-based study, confirms the previously proposed biomarkers and indicates even further heterogeneity of cells in the outer AF and NP of a mature IVD.