Skip to content

Critical roles for the phosphatidylinositide 3-kinase isoforms p110β and p110γ in thrombopoietin-mediated priming of platelet function

Research output: Contribution to journalArticle

Original languageEnglish
Article number1468
Number of pages13
JournalScientific Reports
Volume9
DOIs
DateAccepted/In press - 27 Oct 2018
DatePublished (current) - 6 Feb 2019

Abstract

Thrombopoietin (TPO) enhances platelet activation through activation of the tyrosine kinase; JAK2 and the lipid kinase phosphatidylinositide 3-kinase (PI3K). The aim of our study was to identify the PI3K isoforms involved in mediating the effect of TPO on platelet function and elucidate the underlying mechanism. We found that p110β plays an essential role in TPO-mediated (i) priming of protease-activated receptor (PAR)-mediated integrin αIIbβ3 activation and α-granule secretion, (ii) synergistic enhancement of PAR-mediated activation of the small GTPase RAP1, a regulator of integrin activation and (iii) phosphorylation of the PI3K effector Akt. More importantly, the synergistic effect of TPO on phosphorylation of extracellular-regulated kinase (ERK1/2) and thromboxane (TxA2) synthesis was dependent on both p110β and p110γ. p110β inhibition/deletion, or inhibition of p110γ, resulted in a partial reduction, whereas inhibiting both p110β and p110γ completely prevented the synergistic effect of TPO on ERK1/2 phosphorylation and TxA2 synthesis. The latter was ablated by inhibition of MEK, but not p38, confirming a role for ERK1/2 in regulating TPO-mediated increases in TxA2 synthesis. In conclusion, the synergistic effect of TPO on RAP1 and integrin activation is largely mediated by p110β, whereas p110β and p110γ contribute to the effect of TPO on ERK1/2 phosphorylation and TxA2 formation.

Download statistics

No data available

Documents

Documents

  • Full-text PDF (final published version)

    Rights statement: This is the final published version of the article (version of record). It first appeared online via Springer Nature at https://www.nature.com/articles/s41598-018-37012-9. Please refer to any applicable terms of use of the publisher.

    Final published version, 2 MB, PDF document

    Licence: CC BY

DOI

View research connections

Related faculties, schools or groups