Human EHD2 blocking peptide

Endocytosis has been suggested to be crucial for the induction of plant immunity in several cases. We have previously shown that two Arabidopsis proteins, AtEHD1 and AtEHD2, are involved in endocytosis in plant systems. AtEHD2 has an inhibitory effect on endocytosis of transferrin, FM-4-64, and LeEix2. There are many works in mammalian systems detailing the importance of the various domains in EHDs but, to date, the domains of plant EHD2 that are required for its inhibitory activity on endocytosis remained unknown. In this work we demonstrate that the coiled-coil domain of EHD2 is crucial for the ability of EHD2 to inhibit endocytosis in plants, as mutant EHD2 forms lacking the coiled-coil lost the ability to inhibit endocytosis and signaling of LeEix2. The coiled-coil was also required for binding of EHD2 to the LeEix2 receptor. It is therefore probable that binding of EHD2 to the LeEix2 receptor is required for inhibition of LeEix2 internalization. We also show herein that the P-loop of EHD2 is important for EHD2 to function properly. The EH domain of AtEHD2 does not appear to be involved in inhibition of endocytosis. Moreover, AtEHD2 influences actin organization and may exert its inhibitory effect on endocytosis through actin re-distribution. The coiled-coil domain of EHD2 functions in inhibition of endocytosis, while the EH domain does not appear to be involved in inhibition of endocytosis.

Aim The activation of the TNFR2 receptor is beneficial in several pathologies of the central nervous system, and this study examines whether it can ameliorate the recovery process following spinal cord injury. Methods EHD2-sc-mTNF(R2), an agonist specific for TNFR2, was used to treat neurons exposed to high levels of glutamate in vitro. In vivo, it was infused directly to the spinal cord via osmotic pumps immediately after a contusion to the cord at the T9 level. Locomotion behavior was assessed for 6 weeks, and the tissue was analyzed (lesion size, RNA and protein expression, cell death) after injury. Somatosensory evoked potentials were also measured in response to hindlimb stimulation. Results The activation of TNFR2 protected neurons from glutamate-mediated excitotoxicity through the activation of phosphoinositide-3 kinase gamma in vitro and improved the locomotion of animals following spinal cord injury. The extent of the injury was not affected by infusing EHD2-sc-mTNF(R2), but higher levels of neurofilament H and 2 ', 3 '-cyclic-nucleotide 3 '-phosphodiesterase were observed 6 weeks after the injury. Finally, the activation of TNFR2 after injury increased the neural response recorded in the cortex following hindlimb stimulation. Conclusion The activation of TNFR2 in the spinal cord following contusive injury leads to enhanced locomotion and better cortical responses to hindlimb stimulation.