Neuronal proteins are novel components of podocyte major processes and their expression in glomerular crescents supports their role in crescent formation.

The podocyte has a central role in the glomerular filtration barrier typified by a sophisticated morphology of highly organized primary (major) and secondary (foot) processes. The molecular makeup of foot processes is well characterized, but that of major processes is poorly known. Previously, we profiled the glomerular transcriptome through large-scale sequencing and microarray profiling.

Pdlim2 is a novel actin-regulating protein of podocyte foot processes.

The slit diaphragm and the apical and basal membrane domains of podocytes are connected to each other by an actin-based cytoskeleton critical to the maintenance of the glomerular filtration barrier. In an effort to discover novel regulatory proteins of the podocyte foot process, we identified and characterized pdlim2, a member of the actin-associated LIM protein subfamily of cytosolic proteins typified by an N-terminal PDZ domain and a C-terminal LIM domain. In the kidney, the pdlim2 protein is highly specific for the glomerulus and podocyte foot processes as shown by RT-PCR, western blotting, immunofluorescence, and immunoelectron microscopy.

Expression of novel podocyte-associated proteins sult1b1 and ankrd25.

Background/aims: Podocytes have a unique function in the renal ultrafiltration that is achieved by expressing proteins that are highly specific to podocytes. In this study, we identified two novel podocyte-associated proteins.

Methods: The expression of sult1b1 and ankrd25 in mouse tissues was studied by RT-PCR.