The role of protein structure in genomics Rui

The role of protein structure in genomics Rui Kuang

Why study protein structure? • Genome project provided tremendous amount of data. • Identify genes and determine the biological role of their protein product • Understand their interplay • Three dimensional molecular structure is important for understanding function

From sequence to structure • Significant sequence similarity (>30%) usually suggests strong resemblance in structure • Remote homologous protein can also share similar structure • Structure space can be represented by discrete groups of folds • Yet the boundaries between these classes are often difficult to define

From structure to function • Structure similarity implies evolutionary relationship and functional similarity • However functions can be associated with different structures, different superfamilies can have the same fold and homologous superfamilies can evolve into distinct functions. • 66% of proteins having similar fold also have a similar function

How to study protein structure? • To determine as many structures as possible (X-Ray crystallography and NMR) • Above 24, 000 known structures and functions in Protein Data Bank • Protein structure classification • Protein structure prediction • Protein ranking • Protein segmentation……