Podoplanin, Soluble (PDPN) Rat Active Protein

Function: May be involved in cell migration and/or actin cytoskeleton organization. When expressed in keratinocytes, induces changes in cell morphology with transfected cells showing an elongated shape, numerous membrane protrusions, major reorganization of the actin cytoskeleton, increased motility and decreased cell adhesion. Required for normal lung cell proliferation and alveolus formation at birth. Induces platelet aggregation. Does not have any effect on folic acid or amino acid transport. Does not function as a water channel or as a regulator of aquaporin-type water channels

By similarity.

Subcellular location: Membrane; Single-pass type I membrane protein. Cell projection › lamellipodium membrane; Single-pass type I membrane protein. Cell projection › filopodium membrane; Single-pass type I membrane protein. Cell projection › microvillus membrane; Single-pass type I membrane protein. Cell projection › ruffle membrane; Single-pass type I membrane protein. Note: Localized to actin-rich microvilli and plasma membrane projections such as filopodia, lamellipodia and ruffles. Ref.3

Tissue specificity: In adult kidney, expressed on the urinary surface and foot processes of podocytes and in parietal epithelial cells of Bowman's capsule where it is localized to luminal surfaces. In lung, expressed exclusively on luminal surfaces of type I alveolar epithelial cells and pleural mesothelial cells. Not expressed in type II alveolar cells. In bone, expressed in osteocytes and osteoblasts. In spleen, liver, stomach and intestine, expressed in mesoepithelium. Also expressed in thymic epithelial cells, choroid plexus and leptomeninges. Ref.3 Ref.4

Developmental stage: In newborn kidney, not detected at the vesicle stage. First detected in S-shaped bodies. Ref.3

Post-translational modification: Extensively O-glycosylated. Contains sialic acid residues. O-glycosylation is necessary for platelet aggregation activity. Ref.6The N-terminus is blocked.

Miscellaneous: Down-regulated in puromycin aminonucleoside nephrosis (PAN).

Sequence similarities: Belongs to the podoplanin family.