CNR - Institute of Neuroscience CNR
Institute of Neuroscience
 

Project

New diagnostic tools for familial hemiplegic migraine: genetic and proteomic analysis of P/Q Ca2+ channels

Migraine is a very common neurobiological headache disorder that is caused by increased excitability of the CNS. It is a very disabling medical illness. The economic and societal effect of migraine is substantial: it affects patients' quality of life and impairs work, social activities, and family life. Diagnosis of migraine is based on the characteristics of the headache that it is often associated to neurological symptoms (Aura). It is known from many years that Migranies may have a genetic component but the search for genes involved is not simple and only recently it has ben identify on chromosome19.13 the first gene (CACNA1) involved in a genetic form of inheritable migraine (familial hemiplegic migraine - FHM).

 

This project is aimed to identify new mutations and characterised genetic variants located within the synprint (synaptic protein interaction) region of the CACNA1A gene the CACNA1A gene in order i) to achieve a better definition of the genotype-phenotype correlation in Migraine patients; ii) to better understand the role of mutation and the activity and physiology of the channels, focussing on alpha1A subunit domains involved in the interaction with pre-synaptic proteins (SNARE) (Fig.1); iii) to study variants of the CACNA1A gene associated to Migraine that might have an impact on channel sorting, transport, localization and function and iv) to develop new tools (biochips) for a better and rapid diagniosis of familial hemiplecic migraine.

 

In collaboration with Dr. Carrera (DIBIT, Milan) we are carrying on the search for new mutations and singular nucleotide Polymorphisms (SNPs) in the exonic and intronic region of the CACNA1A gene and we plan to evaluate any effect of these variants in the transport and function of alpha1A subunits after their expression in different cell types including neuroblastoma cell lines (Sy5Y) and neurons. In order to follow the expression, transport and localization of P/Q channels we have developped different tools including new antibodies against the human isoform of alpha1A and GFP-tagged form of alpha1A subunit. Furthermore, alpha1A has been mutagenized and the wild type (wt) and mutant forms have been trasfected in hippocampal neurons.

Preliminary data indicate that the wild type as well as the mutated form of alpha1A (Fig. 2), expressed in hippocampal neurons, are transported to the axon and the nerve terminals.

Prospects for the future

We plan to further investigate the transport of alpha1A subunits to the synapses. In particular we will investigate their stability in synaptic plasma membrane where are expected to associate with the exocytic machinery. This study may provide: A) new tools to study the effect of genetic variants on calcium channels function; B) a better definition of the genotype-phenotype correlation in Migraine patients; C) a basis for assessing the functional abnormalities underlying or predisposing to the disease, critical for the development of new pharmacological therapies; D) a contribution to a better differential diagnosis and prognostic evaluation of the disorder; E) the identification of new biomarkers F) new advanced tools to analyse gene variation; G) a better knowledge on the phisiological role of calcium channel isoforms.

Publications

  • Taverna E, Saba E, Linetti A, Longhi R, Jeromin A, Righi M, Clementi F, Rosa P (2007) Localization of synaptic proteins involved in neurosecretion in different membrane microdomains. J. Neurochem. 100:664-77.
  • Taverna E, Saba E, Rowe J, Francolini M, Clementi F, Rosa P (2004) Role of lipid microdomains in P/Q-type calcium channel (Cav2.1) clustering and function in presynaptic membranes. J. Biol. Chem. 279:5127-34.

Grants

Fondazione Cariplo, Milano

Collaborations

  • P. Carrera, DIBIT-HSR, Milan, Italy.

 

PI photo

Patrizia Rosa

Contact information

email  E-mail

email  +39 02 5031 6974

Participating staff
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