Example:

If you have a gene such as this one Os08g41580 with the sequence below, you can copy and paste the sequence into the blast search window, and hit the search button.
The output from this search can be seen on this page. Blast Output

ubiquitin carboxyl-terminal hydrolase 1, putative, expressed PASA (rice_release4_08302005) AUTOUPDATE: Updated structure of 11978.m08136 (update, updateIDs: 175846, (gene: 11978.t03887, model: 11978.m08136));

LOCN Exon

COOR C/26133646-26134941

Seq to be blasted

 Os08g41580 1296 chr08 C/26133646-26134941