Examining the ZAP70 sequence with InterProScan
In this scenario we will use InterPro to compare the sheep ZAP70 protein sequence with all the sequences in InterPro, a resource that provides functional analysis of protein sequences by classifying them into families and predicting the presence of domains and important sites.
>tr|W5PW03|W5PW03_SHEEP Non-specific protein-tyrosine kinase (Fragment) OS=Ovis aries GN=ZAP70 PE=4 SV=1
PRPAAHLPFFYGSISRAEAEEHLKLAGMADGLFLLRQCLRSLGGYVLSLVHEVRFHHFPIERQLNGTYA
IAGGKAHCGPAELCEFYSRDPDGLPCNLRKPCNRPSGLEPQPGVFDNLRDAMVRDYVRQTWKLEGEALE
QAIISQAPQVEKLIATTAHERMPWYHSSLTREEAERKLYSGSQTDGKFLLRPRKEPGTYALSLIYGKTV
YHYLISQDKAGKYCIPEGTKFDTLWQLVEYLKLKADGLIYCLKEACPNSSASSGAAAPTLPAHPSTFTQ
PQRRIDTLNSDGYTPEPVRLVSSEKPRTMPMDTSVYESPYSDPEELKNKKLFLKRENLLMADIELGCGN
FGSVRQGVYRMRKKQIDVAIKVLKQSTEKGDKDEMMREAQIMHQLDNPYIVRLIGVCQAEALMLVMEMA
GGGPLHKFLVGKKEEIPVSNVAELLHQVSMGMKYLEEKNFVHRDLAARNVLLVNRHYAKISDFGLSKAL
GADDSYYTARSAGKWPLKWYAPECINFRKFSSRSDVWSYGVTMWEAFSYGQKPYKKMKGPEVMAFIEQG
KRMECPPEC
First, let’s go to InterPro, then copy and paste the sequence into the InterPro search box, as shown below, and click on the search button. Your search will take some time to run; be patient.

At the top of the results, you will see the reassuring news that the sheep ZAP70 isoform is indeed a member of the tyrosine protein kinase family. Scrolling down you will see that it has two SH2 domains and a protein tyrosine kinase domain (see the video below about the results). One thing to check is whether our sequence matches the patterns for the active site and ATP binding site, since any mutations in this area may make the protein enzymatically inactive. In this case, however, we can see that sheep ZAP70 isoform contains the protein profile for both the ATP-binding site and the active site (towards the bottom of the page).
Melissa should be safe to use sheep cells in her assay to test tyrosine protein kinase inhibitors!