Analysis of lyn core signaling machinery in neuroacanthocytosis

Neuroacanthocytosis syndromes include the autosomal recessive chorea-acanthocytosis (ChAc) and the X-linked McLeod Syndrome. The common neurological manifestations are dyskinesias, cognitive deterioration and progressive neurodegeneration associated with the presence in peripheral circulation of red blood cells characterized by thorn or spur-like protrusion, known as acanthocytosis. Although different molecular defects are associated with the four neuroacanthocytosis phenotypes (VPS13A, XK, JPH3 and PANK2 genes), the pathophysiology of these disorders and the related abnormalities in red cells is still under investigation. In ChAc, we have recently shown increased Tyrosine-phosphorylation state of several RBC membrane and cytoskeleton, which is associated with independent and strong activation of Lyn, a tyrosine kinase of the Src family. The Src family kinases (SFK), a group of non-receptoral Tyr-kinases, play key regulatory roles in signal transduction pathways in various cellular processes. The activities of SFKs are integrated in a complex and dynamic scenario characterized by interactions with other kinases and/or phosphatases regulating cellular events. The present project has the following aims: Aim 1. Analysis of Lyn kinases signaling network: regulation and identification of new Lyn related pathways in erythroid cells from NA patients. Task 1.1 Analysis of Lyn regulation pathway in NA red cells. Task 1.2. Analysis of expression and activity of SFKs involved in Lyn signaling machinery in NA red cells. Task 1.3. Characterization of Lyn target sites on cytoskelton key protein beta-spectrin in red cells from NA patients. Task 1.4. Analysis of VPS13A expression during erythropoiesis and of Lyn kinase pathways in both ChAc erythropoiesis and VSP13A silenced erythroid precursors Aim 2. Functional analysis of Lyn kinase network in mouse model for Chorea-acanthocytosis Task 2.1 Generation of mouse model for Chorea-acanthocytosis Task 2.2 Phenotypic characterization of mouse model for Chorea-acanthocytosis Task 2.3 In vivo and ex vivo studies on Lyn kinase inhibitors in mouse model for Chorea-acanthocytosis The present project will offer the possibility to progress understanding of the disease, to identify new signaling pathways and to develop new therapeutic tools possibly useful in clinical management of ChAc patients.