Sodium-N-butyrate induces secretion and substrate accumulation of p52 in kirsten sarcoma virus-transformed rat kidney fibroblasts

Abstract 1. 1. A group of five transformation-responsive secreted proteins, ranging in molecular mass from 31 to 70 kDa, were identified in cultured normal rat kidney (NRK) fibroblasts. 2. 2. One such protein (p52) was found to be a major secreted and substrate-attached component of NRK cells. 3. 3. Kirsten sarcoma virus-transformed NRK cells failed to accumulate p52 in either the secreted or substrate-associated protein compartments; this protein was inducible, however, in transformed cells by culture in 2mM sodium- n -butyrate. 4. 4. Kinetics of p52 induction in transformed NRK cells, relative to the time course of increased cell spreading, and its enrichment in the substrate-associated protein fraction suggest that p52 might function in cell-substrate attachment.