Send to

Choose Destination
See comment in PubMed Commons below
Biochim Biophys Acta. 2000 Jul 14;1480(1-2):235-44.

Phosphohexose isomerase/autocrine motility factor/neuroleukin/maturation factor is a multifunctional phosphoprotein.

Author information

  • 1Metastasis Research Program, Karmanos Cancer Institute, Detroit, MI 48201, USA.


Phosphohexose isomerase (PHI) is a member of the ectoenzyme/exoenzyme family and plays a key role in both glycolysis and gluconeogenesis pathways. Upon secretion PHI acts as a cytokine with tumor autocrine motility factor (AMF), neuroleukin (NLK) and maturation factor (MF) functions. Signaling is initiated by its binding to a cell surface 78 kDa glycoprotein (gp78). However, since PHI protein is a 'leaderless' secretory protein, released from cells via a non-classical route(s), we questioned whether the molecule undergoes post-translation modification while retaining proper folding and maintaining intact enzymatic and motogenic activities. To address this, we have generated, expressed and isolated a recombinant human AMF (rhAMF). The rhAMF retained the biological activities of the native AMF, i.e., catalyzes phosphohexose isomerization and stimulated cell motility. Additionally, we show here that human PHI is phosphorylated at serine 185 by casein kinase II (CK II) and we provide experimental evidence suggesting that this phosphorylation is associated with secretion, thus providing insights for elucidating the intracellular signal transmission of cell response to stimulation by AMF/NLK/MF.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center