LacdiNAc (GalNAcβ1-4GlcNAc) Contributes to Self-Renewal of Mouse Embryonic Stem Cells by Regulating Leukemia Inhibitory Factor/STAT3 Signaling

Abstract

Self-renewal of mouse embryonic stem cells (mESCs) is maintained by leukemia inhibitory factor (LIF)/signal transducer and activator of transcription (STAT3) signaling. However, this signaling control does not function in neither mouse epiblast stem cells (mEpiSCs) nor human ESCs (hESCs) or human induced pluripotent stem cells (hiPSCs). To date, the underlying molecular mechanisms that determine this differential LIF-responsiveness have not been clarified. Here, we show that the cell surface glycan LacdiNAc (GalNAcb1-4GlcNAc) is required for LIF/ STAT3 signaling. Undifferentiated state mESCs expressed LacdiNAc at a higher level than differentiated state cells. Knockdown of b4GalNAc-T3 reduced LacdiNAc expression and caused a decrease in LIF/STAT3 signaling that lessened the rate of self-renewal of mESCs. A biochemical analysis showed that LacdiNAc expression on LIF receptor (LIFR) and gp130 was required for the stable localization of the receptors with lipid raft/caveolar components, such as caveolin-1. This localization is required for transduction of a sufficiently strong LIF/STAT3 signal. In primed state pluripotent stem cells, such as hiPSCs and mEpiSC-like cells produced from mESCs, LacdiNAc expression on LIFR and gp130 was extremely weak and the level of localization of these receptors on rafts/caveolae was also low. Furthermore, knockdown of b4GalNAc-T3 decreased LacdiNAc expression and reduced the efficiency of reversion of primed state mEpiSC-like cells into naïve state mESCs. These findings show that the different LIF-responsiveness of naïve state (mESCs) and primed state (mEpiSCs, hESCs, and hiPSCs) cells is dependent on the expression of LacdiNAc on LIFR and gp130 and that this expression is required for the induction and maintenance of the naïve state. STEM CELLS 2011;29:641-650 Disclosure of potential conflicts of interest is found at the end of this article.

β1, 4-N-acetylgalactosaminyltransferase III modulates cancer stemness through EGFR signaling pathway in colon cancer cells

“…We found that B4GALNT3 knockdown decreased LacdiNAc expression of several glycoproteins by biotinylated WFA blotting (Figure 2A, lower penal). OCT4 and NANOG are stem cell associated markers and knockdown of B4GALNT3 suppressed its expression in mouse embryonic stem cells [13]. We therefore investigate whether the expression of OCT4 and NANOG alters in B4GALNT3 knockdown cells.…”

“…However, the underlying mechanisms are still unclear. A recent study showed increased LacdiNAc expression enhances self-renewal of mouse embryonic stem cells and B4GALNT3 knockdown decreases the expression of LacdiNAc [13]. We therefore hypothesized that B4GALNT3 could enhance the cancer stem-like cell property in colorectal cancer.…”

Lacto-N-biosidase Encoded by a Novel Gene of Bifidobacterium longum Subspecies longum Shows Unique Substrate Specificity and Requires a Designated Chaperone for Its Active Expression

“…GalNAc␤1-3GlcNAc is a linkage isomer of LacdiNAc (N,NЈ-diacetyllactosediamine, GalNAc␤1-4GlcNAc) found in the N-glycans of glycoproteins such as lutropin (a hormone produced by gonadotroph cells) and tenascin-R (an extracellular matrix exclusively expressed in the central nervous system) as well as in glycoproteins from parasites (40,41). The LacdiNAc structure in the leukemia inhibitory factor receptor is known to influence self-renewal maintenance of mouse embryonic stem cells (42). Considering that LnbX does not act on LacdiNAc␤-pNP and that GalNAc␤1-3GlcNAc␤-pNP hydrolysis is not inhibited by the presence of LacdiNAc␤-pNP, the enzyme may serve as a new tool for examining the glycan structures of glycoconjugates and for distinguishing between GalNAc␤1-3-GlcNAc and LacdiNAc structures.…”

Trefoil Factor Family Domains Represent Highly Efficient Conformational Determinants for N-Linked N,N′-di-N-acetyllactosediamine (LacdiNAc) Synthesis

“…Recent work has demonstrated the involvement of LacdiNAc in the self-renewal of mouse embryonic stem cells by regulating LIF/STAT3 signaling (42). Undifferentiated state mouse embryonic stem cells expressed LacdiNAc at higher levels than differentiated state cells, and expression of the glycan on the LIF receptor (gp130) was shown to be required for the stable colocalization of the receptor with lipid raft/caveolar proteins, such as caveolin-1, and for the transduction of a sufficiently strong LIF/STAT3 signal.…”