title: O-fucose modulates Notch-controlled blood lineage commitment.
abstract: Notch receptors are cell surface molecules essential for cell fate determination. Notch signaling is subject to tight regulation at multiple levels, including the posttranslational modification of Notch receptors by O-linked fucosylation, a reaction that is catalyzed by protein O-fucosyltransferase-1 (Pofut1). Our previous studies identified a myeloproliferative phenotype in mice conditionally deficient in cellular fucosylation that is attributable to a loss of Notch-dependent suppression of myelopoiesis. Here, we report that hematopoietic stem cells deficient in cellular fucosylation display decreased frequency and defective repopulating ability as well as decreased lymphoid but increased myeloid developmental potential. This phenotype may be attributed to suppressed Notch ligand binding and reduced downstream signaling of Notch activity in hematopoietic stem cells. Consistent with this finding, we further demonstrate that mouse embryonic stem cells deficient in Notch1 (Notch1(-/-)) or Pofut1 (Pofut1(-/-)) fail to generate T lymphocytes but differentiate into myeloid cells while coculturing with Notch ligand-expressing bone marrow stromal cells in vitro. Moreover, in vivo hematopoietic reconstitution of CD34(+) progenitor cells derived from either Notch1(-/-) or Pofut1(-/-) embryonic stem cells show enhanced granulopoiesis with depressed lymphoid lineage development. Together, these results indicate that Notch signaling maintains hematopoietic lineage homeostasis by promoting lymphoid development and suppressing overt myelopoiesis, in part through processes controlled by O-linked fucosylation of Notch receptors.
authors.affiliation: Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA.
authors.forename: Quanjian
authors.initials: Q
authors.lastname: Yan
authors.forename: David
authors.initials: D
authors.lastname: Yao
authors.forename: Lebing L
authors.initials: LL
authors.lastname: Wei
authors.forename: Yuanshuai
authors.initials: Y
authors.lastname: Huang
authors.forename: Jay
authors.initials: J
authors.lastname: Myers
authors.forename: Lihua
authors.initials: L
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Xin
authors.forename: Jeongsup
authors.initials: J
authors.lastname: Shim
authors.forename: Yunfang
authors.initials: Y
authors.lastname: Man
authors.forename: Bronislawa
authors.initials: B
authors.lastname: Petryniak
authors.forename: Stanton
authors.initials: S
authors.lastname: Gerson
authors.forename: John B
authors.initials: JB
authors.lastname: Lowe
authors.forename: Lan
authors.initials: L
authors.lastname: Zhou
mesh_terms: D000818:Animals; D016026:Bone Marrow Transplantation; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D019070:Cell Lineage; D005643:Fucose / Q000737:chemistry / Q000378:metabolism*; D005647:Fucosyltransferases / Q000235:genetics / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D051881:Receptor, Notch1 / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology
chemical_list: D051881:Receptor, Notch1; D005643:Fucose; D005647:Fucosyltransferases; C539426:Pofut1 protein, mouse