Methods and compositions relating to PBK1

A method of identifying a PBK1 modulator, comprising one or more of:

• a) contacting a PBK1 protein with a test agent under conditions that promote kinase activity of said PBK1 protein, and detecting an increase in the kinase activity;
• and
• b) contacting a cell that expresses a PBK1 protein with a test agent under conditions that promote glucose-stimulated insulin secretion from said cell, and detecting an increase in the glucose-stimulated insulin secretion from the cell;
• wherein
• said increase in a) or b) each indicates that the test agent is a PBK1 modulator.

A method of screening for an agent that treats a metabolic disease, said method comprising one or more of:

• a) contacting a PBK1 protein with a test agent under conditions that promote binding of said test agent to said PBK1 protein, and detecting binding of said test agent to said PBK protein;
• b) contacting a PBK1 protein with a test agent under conditions that promote kinase activity of said PBK1 protein, and detecting an increase in the kinase activity;
• and
• c) contacting a cell that expresses a PBK protein with a test agent under conditions that promote glucose-stimulated insulin secretion from said cell, and detecting an increase in the glucose-stimulated insulin secretion from the cell;
• wherein
• said disorder is selected from diabetes, type 2 diabetes, obesity, and diabetic retinopathy.

A method for in vivo screening for an agent that treats diabetes, said method comprising:

• a) subjecting a mammal comprising a PBK1 knockout genome to a diet that promotes diabetes;
• b) treating said mammal with a test agent;
• c) determining blood glucose level of said mammal;
• and
• d) determining whether said mammal is glucose tolerant.