Faculty Opinions recommendation of Sterical hindrance promotes selectivity of the autophagy cargo receptor NDP52 for the danger receptor galectin-8 in antibacterial autophagy.

Author(s):  
Vojo Deretic
2013 ◽  
Vol 6 (261) ◽  
pp. ra9-ra9 ◽  
Author(s):  
S. Li ◽  
M. P. Wandel ◽  
F. Li ◽  
Z. Liu ◽  
C. He ◽  
...  

1979 ◽  
Author(s):  
H. P. Muller ◽  
N. H. van Tilburg ◽  
R. M. Bertina ◽  
J. J. Veltkamp

FVIII was separated into low molecular weight FVIII (LMW FVIII) and high molecular weight FVIII (HMW FVIII) by gel chromatography in the presence of high salt concentration or by high salt elution of LMW FVIII from FVIII bound to anti HMW FVII-Sepharose. Specific antibodies were raised in rabbits against HMW FVIII and LMW FVIII. After removal of the contaminating anti HMW activities the rabbit anti LMW FVIII was still able to neutralize the FVIII coagulant activity of normal plasma and of IMW FVIII with canparable efficiency and it had no effect on the VIIIR:WF of FVIII in normal plasma or in HMW FVIII. Anti LMW FVIII does not bind to HMW FVIII and does not precipitate FVIII as tested by counter immunoelectrophoresis. Rabbit anti HMW FVIII precipitates FVIII in normal plasma, inhibits VIIIR:WF activity, while it has no effect on the FVIII coagulant activity of LMW FVIII. The coagulant activity of FVIII in normal plasma is slightly inhibited by anti HMW FVIII presumably by non-specific effects (sterical hindrance). It is concluded that inhibitory antibodies against VIII:C raised in rabbits recognize antigenic structures only present on LMW FVIII. Antibodies against HMW FVIII raised in rabbits appears to recognize structures only present on HMW FVIII.


2021 ◽  
pp. 100091
Author(s):  
Bingxiang Wang ◽  
Yishi Shen ◽  
Lei Zhai ◽  
Xiaodan Xia ◽  
Hong-mei Gu ◽  
...  

2020 ◽  
Author(s):  
Seth D. Merkley ◽  
Samuel M. Goodfellow ◽  
Yan Guo ◽  
Zoe E.R. Wilton ◽  
Janie R. Byrum ◽  
...  

ABSTRACTIntestinal myeloid cells play a critical role in balancing intestinal homeostasis and inflammation. Here, we report that expression of the autophagy related 5 (Atg5) protein in myeloid cells prevents dysbiosis and excessive intestinal inflammation by limiting IL-12 production. Mice with a selective genetic deletion of Atg5 in myeloid cells (Atg5ΔMye) showed signs of dysbiosis prior to colitis and exhibited severe intestinal inflammation upon colitis induction that was characterized by increased IFNγ production. This increase in IFNγ was due to excess IL-12 secretion from Atg5-deficient myeloid cells. Atg5 functions to limit IL-12 secretion through modulation of late endosome (LE) acidity. Additionally, the autophagy cargo receptor NBR1, which accumulates in Atg5-deficient cells, played a role by delivering IL-12 to LE. Restoration of the intestinal microbiota and alleviation of intestinal inflammation was achieved by genetic deletion of IL-12 in Atg5ΔMye mice. In summary, Atg5 expression in intestinal myeloid cells acts as an anti-inflammatory brake to regulate IL-12 thus preventing dysbiosis and uncontrolled IFNγ-driven intestinal inflammation.


2020 ◽  
Author(s):  
Adriana Savova ◽  
Julia Romanov ◽  
Sascha Martens

SummarySelective autophagy removes harmful intracellular structures such as ubiquitinated, aggregated proteins ensuring cellular homeostasis. This is achieved by the encapsulation of this cargo material within autophagosomes. The cargo receptor p62/SQSTM1 mediates the phase separation of ubiquitinated proteins into condensates, which subsequently become targets for the autophagy machinery. NBR1, another cargo receptor, is a crucial regulator of condensate formation. The mechanisms of the interplay between p62 and NBR1 are not well understood. Employing a fully reconstituted system we show that two domains of NBR1, the PB1 domain which binds to p62 and the UBA domain which binds to ubiquitin, are required to promote p62-ubiquitin condensate formation. In cells, acute depletion of endogenous NBR1 reduces formation of p62 condensates, a phenotype that can be rescued by re-expression of wild-type NBR1, but not PB1 or UBA domain mutants. Our results provide mechanistic insights into the role of NBR1 in selective autophagy.


2021 ◽  
Vol 12 ◽  
Author(s):  
Shady Estfanous ◽  
Kylene P. Daily ◽  
Mostafa Eltobgy ◽  
Nicholas P. Deems ◽  
Midhun N. K. Anne ◽  
...  

Autophagy is a proposed route of amyloid-β (Aβ) clearance by microglia that is halted in Alzheimer’s Disease (AD), though mechanisms underlying this dysfunction remain elusive. Here, primary microglia from adult AD (5xFAD) mice were utilized to demonstrate that 5xFAD microglia fail to degrade Aβ and express low levels of autophagy cargo receptor NBR1. In 5xFAD mouse brains, we show for the first time that AD microglia express elevated levels of microRNA cluster Mirc1/Mir17-92a, which is known to downregulate autophagy proteins. By in situ hybridization in post-mortem AD human tissue sections, we observed that the Mirc1/Mir17-92a cluster member miR-17 is also elevated in human AD microglia, specifically in the vicinity of Aβ deposits, compared to non-disease controls. We show that NBR1 expression is negatively correlated with expression of miR-17 in human AD microglia via immunohistopathologic staining in human AD brain tissue sections. We demonstrate in healthy microglia that autophagy cargo receptor NBR1 is required for Aβ degradation. Inhibiting elevated miR-17 in 5xFAD mouse microglia improves Aβ degradation, autophagy, and NBR1 puncta formation in vitro and improves NBR1 expression in vivo. These findings offer a mechanism behind dysfunctional autophagy in AD microglia which may be useful for therapeutic interventions aiming to improve autophagy function in AD.


2018 ◽  
Author(s):  
Brian T Emmer ◽  
Geoffrey G Hesketh ◽  
Emilee Kotnik ◽  
Vi T Tang ◽  
Paul J Lascuna ◽  
...  

1999 ◽  
Vol 54 (9) ◽  
pp. 1133-1137
Author(s):  
Astrid Knieß ◽  
Margit Gruner ◽  
Roland Mayer

ß-Oxo-1 and 9-anthracenepropionate (6 and 7) reacts with DMF-acetale to enaminones 10 and 11. The reaction of 2-(dimethylamino)methylen-substituted ß-oxo-1 -anthracenepropionate (10) with hydrazines yields 5-(l-anthracenyl)-pyrazol-4-carboxylates (13). In contrast, the cyclocondensation of 3-(9-anthracenyl)-2-(dimethylamino)methylen-3-oxo-propionate (11) with hydrazine hydrochlorides gives 4-(9-anthracenoyl)-5-hydroxy-pyrazoles (14). This is caused by the sterical hindrance of the carbonyl group of the anthracene derivatives in position 9; thus, the cyclocondensation proceeds via reaction of the ester group of the enaminone 11.


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