Hepatocyte growth factor activates phosphoinositide 3-kinase C2 beta in renal brush-border plasma membranes

The Biochemical Journal
Vladiana CrljenH Banfić

Abstract

Upon stimulation of renal cortical slices with hepatocyte growth factor (HGF), inositol lipid metabolism was studied in basal-lateral plasma membranes (BLM) and brush-border plasma membranes (BBM). Whereas in BLM rapid increases in 1,2-diacylglycerol, PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2) were observed, suggesting that in BLM HGF activates both phospholipase C (PLC) and phosphoinositide 3-kinase (PI3K), in BBM only HGF-induced transient accumulation of PtdIns3P was seen, which was temporarily delayed from signalling events in BLM and could be blocked by the PtdIns-specific-PLC inhibitor ET-18-OCH(3) and the calpain inhibitor calpeptin, suggesting that 3-kinase activation in BBM lies downstream of PLC activation in BLM and is a calpain-mediated event. Moreover, the increase in immunoprecipitable PI3K-C2 beta activity, which is sensitive to wortmannin (10 nM) and shows strong preference for PtdIns over PtdIns4P as a substrate, was observed only in BBM upon stimulation of renal cortical slices with HGF and could be mimicked by the Ca(2+) ionophore A23187 and blocked by the cell-penetrant Ca(2+) chelator BAPTA-AM [1,2-bis-(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid tetrakis(acetoxymethyl ester)]. On Western blots PI3K-C2 bet...Continue Reading

Citations

Nov 30, 2005·Molecular and Cellular Biology·Kazutoshi HaradaPaul A Khavari
Oct 16, 2015·Journal of Receptor and Signal Transduction Research·Song Mao, Jianhua Zhang
Jul 22, 2006·Advances in Enzyme Regulation·Aleksandra SindićHrvoje Banfić
Sep 1, 2004·Experimental Biology and Medicine·Vladimir TrkuljaZdravko Lackovic

❮ Previous
Next ❯

Related Concepts

Related Feeds

Autophagosome

An autophagosome is the formation of double-membrane vesicles that involve numerous proteins and cytoplasmic components. These double-membrane vesicles are then terminated at the lysosome where they are degraded. Discover the latest research on autophagosomes here.

AKT Pathway

This feed focuses on the AKT serine/threonine kinase, which is an important signaling pathway involved in processes such as glucose metabolism and cell survival.

Autophagosome

An autophagosome is the formation of double-membrane vesicles that involve numerous proteins and cytoplasmic components. These double-membrane vesicles are then terminated at the lysosome where they are degraded. Discover the latest research on autophagosomes here.