I-TASSER server is an Internet service for full-length protein 3D structure prediction. When users submit an amino acid sequence, the server will try to retrieve similar folds and super-secondary structures from PDB by the profile-profile alignment (PPA) threading technique. In the next step, I-TASSER will build full-length models by reassembling the continuous fragments excised from the PDB templates with unaligned loop regions constructed by ab initio folding. A second round reassembly simulation is then followed with the purpose of refining the global and local structures. The models of the lowest free-energy are finally returned to the users with the modeling accuracy estimated. The I-TASSER server (as 'Zhang-Server') was ranked as the No 1 server in the recent CASP7 experiment. The structural assembly simulations take serveral hours to days depends on our job queue. If you need a quicker response, we recommend you to use our LOMETS (meta-server) or MUSTER (single-server fold-recognition).

• Click here to take a look at the I-TASSER models predicted in CASP7.
• Click here to view the overall rank of all groups in the CASP7 server section.
• Click here to download the general I-TASSER potentials.
• Click here to download the I-TASSER structure decoys.
• Click here to submit a sequence to the I-TASSER server.
• Click here to check out the pending and finished jobs in the I-TASSER server.
• Click here if you want to remove the models of your target from the I-TASSER server.

The output of the I-TASSER server includes (other features are in development, all models are kept on our server for 365 days):

• Up to five full-length models (ranked by cluster density)
• Estimated accuracy of the first model (including a confidence score, predicted TM-score and RMSD)
• Images of the top five models

Contact
The I-TASSER server is in active development with the goal to provide accurate protein structure models using the state-of-the-art methodologies. Please send us your questions and comments by email: zhanglab@ku.edu.