title: RNAi screen identifies Jarid1b as a major regulator of mouse HSC activity.
abstract: Histone methylation is a dynamic and reversible process proposed to directly impact on stem cell fate. The Jumonji (JmjC) domain-containing family of demethylases comprises 27 members that target mono-, di-, and trimethylated lysine residues of histone (or nonhistone) proteins. To evaluate their role in regulation of hematopoietic stem cell (HSC) behavior, we performed an in vivo RNAi-based functional screen and demonstrated that Jarid1b and Jhdm1f play opposing roles in regulation of HSC activity. Decrease in Jarid1b levels correlated with an in vitro expansion of HSCs with preserved long-term in vivo lymphomyeloid differentiation potential. Through RNA sequencing analysis, Jarid1b knockdown was associated with increased expression levels of several HSC regulators (Hoxa7, Hoxa9, Hoxa10, Hes1, Gata2) and reduced levels of differentiation-associated genes. shRNA against Jhdmlf, in contrast, impaired hematopoietic reconstitution of bone marrow cells. Together, our studies identified Jarid1b as a negative regulator of HSC activity and Jhdmlf as a positive regulator of HSC activity.
authors.affiliation: Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada.
authors.forename: Sonia
authors.initials: S
authors.lastname: Cellot
authors.forename: Kristin J
authors.initials: KJ
authors.lastname: Hope
authors.forename: Jalila
authors.initials: J
authors.lastname: Chagraoui
authors.forename: Martin
authors.initials: M
authors.lastname: Sauvageau
authors.forename: Éric
authors.initials: É
authors.lastname: Deneault
authors.forename: Tara
authors.initials: T
authors.lastname: MacRae
authors.forename: Nadine
authors.initials: N
authors.lastname: Mayotte
authors.forename: Brian T
authors.initials: BT
authors.lastname: Wilhelm
authors.forename: Josette R
authors.initials: JR
authors.lastname: Landry
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Ting
authors.forename: Jana
authors.initials: J
authors.lastname: Krosl
authors.forename: Keith
authors.initials: K
authors.lastname: Humphries
authors.forename: Alexander
authors.initials: A
authors.lastname: Thompson
authors.forename: Guy
authors.initials: G
authors.lastname: Sauvageau
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects; D055785:Gene Knockdown Techniques; D006410:Hematopoiesis / Q000187:drug effects / Q000235:genetics*; D006412:Hematopoietic Stem Cells / Q000378:metabolism / Q000502:physiology*; D057166:High-Throughput Screening Assays / Q000379:methods*; D056466:Histone Demethylases / Q000235:genetics / Q000502:physiology; D056484:Jumonji Domain-Containing Histone Demethylases / Q000235:genetics / Q000502:physiology*; D051379:Mice; D020297:Mice, Congenic; D008810:Mice, Inbred C57BL; D034622:RNA Interference / Q000502:physiology*; D034741:RNA, Small Interfering / Q000235:genetics / Q000494:pharmacology; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology; D054928:Validation Studies as Topic
chemical_list: D004268:DNA-Binding Proteins; D034741:RNA, Small Interfering; D014157:Transcription Factors; D056466:Histone Demethylases; D056484:Jumonji Domain-Containing Histone Demethylases; C485614:Kdm5b protein, mouse; C553256:PHF8 protein, mouse