Gene expression in mouse Lhx2 knock out embryo (E16.5) vs FVB controls

ABSTRACT: The Lhx2 transcription factor plays essential roles in morphogenesis and patterning of ectodermal derivatives, as well as in controlling stem cell activity. Lhx2 is expressed in the hair follicle (HF) buds, while in postnatal telogen HFs Lhx2+ cells reside in the stem cell-enriched epithelial compartments (bulge, secondary hair germ) and co-express selected stem cell markers (Sox9, Tcf4 and Lgr5). Lhx2+ cells represent the vast majority of cells in the bulge and secondary hair germ that proliferate in response to skin injury. This is functionally important, since the wound re-epithelialization is significantly retarded in heterozygous Lhx2 knockout (+/-) mice, while anagen onset in the HFs located closely to the wound is accelerated compared to wild-type mice. Cell proliferation in the bulge and the number of Sox9+ and Tcf4+ cells in the HFs closely adjacent to the wound in Lhx2+/- mice are decreased in comparison to wild-type controls, while expression of Lgr5 and cell proliferation in the secondary hair germ are increased. Furthermore, acceleration of wound-induced anagen development in Lhx2+/- mice is inhibited by administration of Lgr5 siRNA. In addition, Chip-on-chip/ChIP-qPCR and reporter assay analyses reveal Sox9, Tcf4 and Lgr5 as direct Lhx2 targets in keratinocytes. These data strongly suggest that Lhx2 positively regulates Sox9 and Tcf4 in the bulge cells and promotes wound re-epithelization, while it simultaneously negatively regulates Lgr5 in the secondary hair germ and inhibits HF cycling. Thus, Lhx2 operates as a regulator of epithelial stem cell activity during skin response to injury. Total RNA derived from Lhx2KO and WT embryos was subjected to a dual-color microarray analysis, in which the RNA from Lhx2KO embryo was labelled with Cy3 and that of WT embryo with Cy5 respectivly

ORGANISM(S): Mus musculus

SUBMITTER: Andrei Mardaryev 

PROVIDER: E-GEOD-32511 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress