title: Imprinted genes that regulate early mammalian growth are coexpressed in somatic stem cells.
abstract: Lifelong, many somatic tissues are replenished by specialized adult stem cells. These stem cells are generally rare, infrequently dividing, occupy a unique niche, and can rapidly respond to injury to maintain a steady tissue size. Despite these commonalities, few shared regulatory mechanisms have been identified. Here, we scrutinized data comparing genes expressed in murine long-term hematopoietic stem cells with their differentiated counterparts and observed that a disproportionate number were members of the developmentally-important, monoallelically expressed imprinted genes. Studying a subset, which are members of a purported imprinted gene network (IGN), we found their expression in HSCs rapidly altered upon hematopoietic perturbations. These imprinted genes were also predominantly expressed in stem/progenitor cells of the adult epidermis and skeletal muscle in mice, relative to their differentiated counterparts. The parallel down-regulation of these genes postnatally in response to proliferation and differentiation suggests that the IGN could play a mechanistic role in both cell growth and tissue homeostasis.
authors: Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America.
authors: Jonathan S
authors: JS
authors: Berg
authors: Kuanyin K
authors: KK
authors: Lin
authors: Corinne
authors: C
authors: Sonnet
authors: Nathan C
authors: NC
authors: Boles
authors: David C
authors: DC
authors: Weksberg
authors: Hoang
authors: H
authors: Nguyen
authors: Lowenna J
authors: LJ
authors: Holt
authors: Danny
authors: D
authors: Rickwood
authors: Roger J
authors: RJ
authors: Daly
authors: Margaret A
authors: MA
authors: Goodell
mesh_terms: D000818:Animals; D018507:Gene Expression Regulation, Developmental; D020868:Gene Silencing; D018392:Genomic Imprinting; D006412:Hematopoietic Stem Cells / Q000378:metabolism; D006801:Humans; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction