The long term focus of this project is to clarify the role of growth factors in mesangial cell proliferation and the eventual sclerosis of the glomerular microvascular bed. The objective is to investigate the role of the serine/threonine protein kinase, Akt in the biologic response of glomerular mesangial cells. This proposal will determine the role of Akt in this response, by assessing the role that Akt plays in glomerular cell proliferation and migration, identifying what substance(s) produced by the mesangial cell regulate(s) the activity of Akt as well as identifying mesangial cell substrates for the enzyme. The effect of PDGF on Akt activity in glomerular mesangial cells will be determined. Key experiments will determine the effect of altered Akt activity on proliferation and migration using transfected dominant negative and constitutively active constructs. The yeast two hybrid system will be utilized to identify protein sequences that interact with either the Akt homology domain or with the kinase domain. Additionally the effect of regulatory protein(s) identified in the yeast two hybrid screen will be investigated by the use of either dominant negative constructs or antisense probes.
