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Biology subjects

Kessels, H.

Publications and source records attributed to Kessels, H..

2 recordsLinked to original sources

GFRAL neurons remodel intestinal structure and type 2 immunity

The brain has emerged as a key regulator of immune functions, but the underlying neural mechanisms remain poorly understood. Here we show that brainstem GFRAL-expressing neurons prime type 2 immunity and shape intestinal epithelial structure in mice. Type 2 inflammation results in activation of GFRAL neurons and potentiation of their excitatory synaptic inputs. Enhancing GFRAL neuron excitability is sufficient to remodel intestinal type 2 immunity through a polysynaptic vagal brain-gut circuit, expanding tuft and goblet cell populations and increasing intestinal type 2 cytokine expression; while inhibiting GFRAL neurons leads to largely opposite changes. Accordingly, manipulating GFRAL neuron function reshapes intestinal structure and pathophysiology in food allergy, helminth infection and colitis models. Thus, GFRAL neurons orchestrate type 2 immune responses to facilitate recovery from intestinal diseases.

neuroscience↗

β-amyloid-driven synaptic depression requires PDZ protein interaction at AMPA-receptor subunit GluA3

Soluble oligomeric amyloid-{beta} (A{beta}) is a prime suspect to cause cognitive deficits in Alzheimers disease and weakens synapses by removing AMPA-type glutamate receptors (AMPARs). We show that synapses of CA1 pyramidal neurons become vulnerable to A{beta} when they express AMPAR subunit GluA3. We found that A{beta}-oligomers reduce the levels of GluA3 immobilized at spines, indicating they deplete GluA3-containing AMPARs from synapses. These A{beta}-driven effects critically depended on the PDZ-binding motif of GluA3. When GluA3 was expressed with a single amino acid mutation in its PDZ-binding motif that prevents GRIP binding, it did not end up at spines and A{beta} failed to trigger synaptic depression. GluA3 with a different point mutation in the PDZ-motif that leaves GRIP-binding intact but prevents its endocytosis, was present at spines in normal amounts but was fully resistant to effects of A{beta}. Our data indicate that A{beta}-mediated synaptic depression requires the removal of GluA3 from synapses. We propose that GRIP-detachment from GluA3 is a critical early step in the cascade of events through which A{beta} accumulation causes a loss of synapse.

neuroscience↗