Colloquia - Dr. Yang Zhang/University of Michigan, "Genome-wide protein structure prediction and structure-based function annotation", ACES 6.304

Contact Name: 
Jenna Whitney
Date: 
Mar 8, 2012 3:30pm - 4:30pm

Type of Talk: Colloquia

Speaker/Affiliation: Dr. Yang Zhan

g/University of Michigan

Talk Audience: UTCS Faculty and Graduate Stud

ents

Date/Time: Thursday, March 8, 2012, 3:30 pm

Location: ACE

S 6.304

Host: Dr. Chandrajit Bajaj

Talk Title: Genome-wide protei

n structure prediction and structure-based function annotation

Abstrac

t:
The biological function of protein molecules is determined by the shap

e of their three-dimensional structures. Is it possible to predict protein

structure and function from the amino acid sequence? We developed a new alg

orithm, I-TASSER, which assembles atomic structure of proteins using frag

ments excised from unrelated experiment structures. Functional insights(e.g

. ligand-binding affinity, enzyme classification and gene ontology) are th

en deduced by matching the predicted structure models with the known protei

ns in protein function libraries. The I-TASSER algorithm was ranked as the

best for automated protein structure prediction in the community wide CASP

experiments of 2006, 2008 and 2010 it was also ranked at the top for prote

in function annotation in CASP9 in 2010.

In this talk, we first revie

w the recent progress in computer-based protein structure prediction includ

ing the new developments in ab initio folding and atomic structure refineme

nts since the CASP9 experiment, and show that the protein structure predic

tion problem can in principle be solved using the current PDB library. Next

, we discuss the application of the developed methods to the structural an

d functional modeling of a number of genomes, including all G-protein coup

led receptors (GPCRs) in the human genome, yielding models 90% of which ar

e shown to have correct topology, and Marekā€šs disease virus, the first

success of the computational modeling of a complete viral genome. Finally,
we demonstrate how the predicted I-TASSER structure models can be used to

annotate the biological function of the proteins and screening drug candida

tes by matching their global topology and functional sites against the exis

ting structure/function/binding databases.