Initial charactization of murine Lgr6+ Epidermal Stem Cells
- Authors
- Bastidas Torres, Armando Nicol?s
- Format
- MasterThesis
- Status
- publishedVersion
- Description
Adult stem cells (ASCs) are undifferentiated cells that replace damaged and dead cells in organs. ASCs have recently being hypothesized as initiators of cancer due to their long residence time in the body which might allow them to accumulate more mutations and epigenetic abnormalities than mature cells. In the murine skin, the 7-TM protein Lgr6 marks an ASC population residing in the hair follicle (HF) capable of producing all skin cell lineages in homeostasis and wound healing. Lgr proteins are characterized by a leucine-rich repeat containing N-terminal domain, and are known to enhance Wnt pathway activation. The role of Lgr6 in physiology remains unknown but its high homology with Lgr4 and 5 suggests it might be important in embryonic development. Remarkably, transgenic mice reported as null for Lgr6 due to the disruption of this locus with an EGFP-Ires-CreERT2 construct are viable and fertile. In this study, we assessed the presence of Lgr6 transcripts in frozen skin samples and sorted epidermal cell populations from homozygous and heterozygous Lgr6 knock-in mice by RT-qPCR. Additionally, Wnt pathway activation was evaluated in basal layer Lgr6- and Lgr6+ cells by detecting Wnt pathway target genes (Cyclin D1 and Myc) and Axin2, a signal transduction component of the pathway. Finally, the expression of three other epidermal stem cell markers (Gli1, Lrig1 and Plet1) was assessed in the basal layer Lgr6- and Lgr6+ keratinocytes. The results showed that unlike reported; Lgr6 is expressed in homozygous and heterozygous Lgr6 knock-in mice. However, the homozygous knock-in animals seem to express variant(s) of Lgr6 that lack exon 1. The Wnt pathway was shown to be slightly upregulated in the basal layer Lgr6+ cells compared to their negative counterparts based on Axin2 and Cyclin D1 expression. Finally, Gli1 expression was found to be higher in basal layer Lgr6+ cells compared to the Lgr6- population, suggesting this marker might be a suitable alternative for the identification of skin stem cells.
- Publication Year
- 2013
- Language
- eng
- Topic
- C?LULAS MADRE
FOL?CULO PILOSO
CIENCIAS DE LA VIDA
TECNOLOG?A
- Repository
- Repositorio SENESCYT
- Rights
- openAccess
- License
- openAccess