scholarly journals Radical and lunatic fringes modulate notch ligands to support mammalian intestinal homeostasis

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Preetish Kadur Lakshminarasimha Murthy ◽  
Tara Srinivasan ◽  
Matthew S Bochter ◽  
Rui Xi ◽  
Anastasia Kristine Varanko ◽  
...  

Notch signalling maintains stem cell regeneration at the mouse intestinal crypt base and balances the absorptive and secretory lineages in the upper crypt and villus. Here we report the role of Fringe family of glycosyltransferases in modulating Notch activity in the two compartments. At the crypt base, RFNG is enriched in the Paneth cells and increases cell surface expression of DLL1 and DLL4. This promotes Notch activity in the neighbouring Lgr5+ stem cells assisting their self-renewal. Expressed by various secretory cells in the upper crypt and villus, LFNG promotes DLL surface expression and suppresses the secretory lineage . Hence, in the intestinal epithelium, Fringes are present in the ligand-presenting ‘sender’ secretory cells and promote Notch activity in the neighbouring ‘receiver’ cells. Fringes thereby provide for targeted modulation of Notch activity and thus the cell fate in the stem cell zone, or the upper crypt and villus.

2012 ◽  
Vol 72 (7) ◽  
pp. 1068-1084 ◽  
Author(s):  
Allison M. Bond ◽  
Oneil G. Bhalala ◽  
John A. Kessler

Author(s):  
Raymond Rowland ◽  
Alberto Brandariz-Nuñez

Understanding the role of glycosylation in the virus-receptor interaction is important for developing approaches that disrupt infection. In this study, we showed that deglycosylation of both ACE2 and S had a minimal effect on the spike-ACE2 interaction.


2019 ◽  
Vol 106 ◽  
pp. 49-56 ◽  
Author(s):  
Natalia Sánchez-Romero ◽  
Pilar Sainz-Arnal ◽  
Iris Pla-Palacín ◽  
Pablo Royo Dachary ◽  
Helen Almeida ◽  
...  

2005 ◽  
Vol 14 (2) ◽  
pp. 140-152 ◽  
Author(s):  
Gurudutta U. Gangenahalli ◽  
Pallavi Gupta ◽  
Daman Saluja ◽  
Yogesh K. Verma ◽  
Vimal Kishore ◽  
...  

2020 ◽  
Vol 21 (17) ◽  
pp. 6181
Author(s):  
Sara Cruciani ◽  
Giuseppe Garroni ◽  
Francesca Balzano ◽  
Renzo Pala ◽  
Emanuela Bellu ◽  
...  

Fat tissue represents an important source of adipose-derived stem cells (ADSCs), which can differentiate towards several phenotypes under certain stimuli. Definite molecules as vitamin D are able to influence stem cell fate, acting on the expression of specific genes. In addition, miRNAs are important modulating factors in obesity and numerous diseases. We previously identified specific conditioned media able to commit stem cells towards defined cellular phenotypes. In the present paper, we aimed at evaluating the role of metformin on ADSCs differentiation. In particular, ADSCs were cultured in a specific adipogenic conditioned medium (MD), in the presence of metformin, alone or in combination with vitamin D. Our results showed that the combination of the two compounds is able to counteract the appearance of an adipogenic phenotype, indicating a feedforward regulation on vitamin D metabolism by metformin, acting on CYP27B1 and CYP3A4. We then evaluated the role of specific epigenetic modulating genes and miRNAs in controlling stem cell adipogenesis. The combination of the two molecules was able to influence stem cell fate, by modulating the adipogenic phenotype, suggesting their possible application in clinical practice in counteracting uncontrolled lipogenesis and obesity-related diseases.


2000 ◽  
Vol 279 (6) ◽  
pp. L1129-L1136 ◽  
Author(s):  
Darren D. Browning ◽  
Wade C. Diehl ◽  
Matthew H. Hsu ◽  
Ingrid U. Schraufstatter ◽  
Richard D. Ye

Interleukin (IL)-8 is a C-X-C chemokine that plays an important role in acute inflammation through its G protein-coupled receptors CXCR1 and CXCR2. In this study, we investigated the role of IL-8 as an autocrine regulator of IL-8 production and the signaling mechanisms involved in human peripheral blood mononuclear cells (MNCs). Sepharose-immobilized IL-8 stimulated a sevenfold increase in IL-8 production within 2 h. IL-8 induced the expression of its own message, and IL-8 biosynthesis was inhibited by cycloheximide and actinomycin D, indicating de novo RNA and protein synthesis. In contrast to MNCs, polymorphonuclear neutrophils did not respond to the immobilized IL-8 with IL-8 production despite cell surface expression of CXCR1 and CXCR2. Melanoma growth-stimulatory activity/growth-related protein-α (MGSA/GROα), which binds CXCR2 but not CXCR1, was unable to either stimulate IL-8 secretion in MNCs or desensitize these cells to respond to immobilized IL-8. The involvement of mitogen-activated protein kinase (MAPK) in IL-8-induced IL-8 biosynthesis was suggested by the ability of PD-98059, an inhibitor of MAPK kinase, to block this function. Furthermore, IL-8 induced a significant increase in extracellular signal-regulated kinase 2 phosphorylation, whereas MGSA/GROα was much less effective. These findings support the role of IL-8 as an autocrine regulator of IL-8 production and suggest that this function is mediated by CXCR1 through activation of MAPK.


Nature ◽  
2002 ◽  
Vol 416 (6883) ◽  
pp. 854-860 ◽  
Author(s):  
Emi K. Nishimura ◽  
Siobhán A. Jordan ◽  
Hideo Oshima ◽  
Hisahiro Yoshida ◽  
Masatake Osawa ◽  
...  

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