I-TASSER is a bioinformatics method for predicting three-dimensional structure model of protein molecules from amino acid sequences. It detects structure templates from the Protein Data Bank by a technique called fold recognition. The full-length structure models are constructed by reassembling structural fragments from threading templates using replica exchangeMonte Carlo simulations. I-TASSER is one of the most successful protein structure prediction methods in the community-wide CASP experiments. I-TASSER has been extended for structure-based protein function predictions, which provides annotations on ligandbinding site, gene ontology and enzyme commission by structurally matching structural models of the target protein to the known proteins in protein function databases. It has an on-line server built in the at the University of Michigan, Ann Arbor, allowing users to submit sequences and obtain structure and function predictions. A standalone package of I-TASSER is available for download at the .
Ranking in CASP
I-TASSER has been consistently ranked as the top method in CASP, a community-wide experiment to benchmark the best structure prediction methods in the field of protein folding and protein structure prediction. CASP takes place every two years since 1994.
No 1 in CASP7
No 1 in CASP8 :
No 2 in CASP9 :
No 1 in CASP10 :
No 1 in CASP11 :
No 1 in CASP12 :
Method and pipeline
I-TASSER is a template-based method for protein structure and function prediction. The pipeline consists of six consecutive steps:
The I-TASSER Suite is a downloadable package of standalone computer programs, developed by the Yang Zhang Lab for protein structure prediction and refinement, and structure-based protein function annotations. Through the I-TASSER License, researchers have access to the following standalone programs:
I-TASSER: A standalone I-TASSER package for protein 3D structure prediction and refinement.
COACH: A function annotation program based on COFACTOR, TM-SITE and S-SITE.
COFACTOR: A program for ligand-binding site, EC number & GO term prediction.
TM-SITE: A structure-based approach for ligand-binding site prediction.
S-SITE: A sequence-based approach for ligand-binding site prediction.
LOMETS: A set of locally installed threading programs for meta-server protein fold-recognition.
MUSTER: A threading program to identify templates from a non-redundant protein structure library.
SPICKER: A clustering program to identify near-native protein model from structure decoys.
HAAD: A program for quickly adding hydrogen atoms to protein heavy-atom structures.
EDTSurf: A program to construct triangulated surfaces of protein molecules.
ModRefiner: A program to construct and refine atomic-level protein models from C-alpha traces.