Focal adhesion kinase PTK2 autophosphorylation is not required for the activation of sodium–hydrogen exchange by decreased cell volume in the preimplantation mouse embryo
Autor: | Jane C Fenelon, Jay M. Baltz, Baozeng Xu |
---|---|
Rok vydání: | 2019 |
Předmět: |
Indoles
Cell PTK2 Embryonic Development Focal adhesion Mice 03 medical and health sciences 0302 clinical medicine medicine Animals Phosphorylation Cell Size 030304 developmental biology Sulfonamides 0303 health sciences Sodium-Hydrogen Exchanger 1 030219 obstetrics & reproductive medicine Chemistry Kinase Sodium Autophosphorylation Cell Biology Cell biology Blastocyst medicine.anatomical_structure Focal Adhesion Kinase 1 Tyrosine Female Signal transduction Intracellular Hydrogen Signal Transduction Developmental Biology |
Zdroj: | Zygote. 27:173-179 |
ISSN: | 1469-8730 0967-1994 |
DOI: | 10.1017/s0967199419000212 |
Popis: | SummaryRecovery from decreased cell volume is accomplished by a regulated increase of intracellular osmolarity. The acute response is activation of inorganic ion transport into the cell, the main effector of which is the Na+/H+ exchanger NHE1. NHE1 is rapidly activated by a cell volume decrease in early embryos, but how this occurs is incompletely understood. Elucidating cell volume-regulatory mechanisms in early embryos is important, as it has been shown that their dysregulation results in preimplantation developmental arrest. The kinase JAK2 has a role in volume-mediated NHE1 activation in at least some cells, including 2-cell stage mouse embryos. However, while 2-cell embryos show partial inhibition of NHE1 when JAK2 activity is blocked, NHE1 activation in 1-cell embryos is JAK2-independent, implying a requirement for additional signalling mechanisms. As focal adhesion kinase (FAK aka PTK2) becomes phosphorylated and activated in some cell types in response to decreased cell volume, we sought to determine whether it was involved in NHE1 activation in the early mouse embryo. FAK activity requires initial autophosphorylation of a tyrosine residue, Y397. However, FAK Y397 phosphorylation levels were not increased in either 1- or 2-cell embryos after cell volume was decreased. Furthermore, the selective FAK inhibitor PF-562271 did not affect NHE1 activation at concentrations that essentially eliminated Y397 phosphorylation. Thus, autophosphorylation of FAK Y397 does not appear to be required for NHE1 activation induced by a decrease in cell volume in early mouse embryos. |
Databáze: | OpenAIRE |
Externí odkaz: |