If I understood your question correct then may be this links would help you:

1) http://www.ncbi.nlm.nih.gov/guide/howto/obtain-genomic-sequence/

2) https://www.google.nl/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CDgQFjAB&url=http%3A%2F%2Fmyweb.brooklyn.liu.edu%2Flmarsh%2Fvina.ppt&ei=0V1WU4P_KpOW0QWPioHwDw&usg=AFQjCNGYAMXK1h5IMfRS1TuyKBo_ZBzDRg&sig2=-mKmrdfAoEzv-NXpKIf3hg&bvm=bv.65177938,d.d2k

or If not then ask me a specific one.

Goodluck

Thank you Sir for your valuable reply.I just had a glance,but surely I'l find a solution in that.

Will get you if any further queries

Use the following steps:

1) Go to NCBI website at http://www.ncbi.nlm.nih.gov/

2) Change the search query data base into : Nucleotide

3) Use the following keyword to search your gene: P2X receptors

4) Click SEARCH

5) You will be presented with a number of P2X receptors nucleotide accessions

6) You can select ones that are suitable with what you are looking for...

Here is link to the result of step 5:

http://www.ncbi.nlm.nih.gov/nuccore/?term=P2X+receptors

Here is link to one data base accession obtained from the search:

http://www.ncbi.nlm.nih.gov/nuccore/NM_008771.3

You can use the sequence to analyze what you want, such as ligand binding site, etc.

Good luck...