title: Developmentally acquired PKA localisation in mouse oocytes and embryos.
abstract: Localisation of Protein Kinase A (PKA) by A-Kinase Anchoring Proteins (AKAPs) is known to coordinate localised signalling complexes that target cAMP-mediated signalling to specific cellular sub-domains. The cAMP PKA signalling pathway is implicated in both meiotic arrest and meiotic resumption, thus spatio-temporal changes in PKA localisation during development may determine the oocytes response to changes in cAMP. In this study we aim to establish whether changes in PKA localisation occur during oocyte and early embryo development. Using fluorescently-labelled PKA constructs we show that in meiotically incompetent oocytes PKA is distributed throughout the cytoplasm and shows no punctuate localisation. As meiotic competence is acquired, PKA associates with mitochondria. Immature germinal vesicle (GV) stage oocytes show an aggregation of PKA around the GV and PKA remains co-localised with mitochondria throughout oocyte maturation. After fertilisation, the punctuate, mitochondrial distribution was lost, such that by the 2-cell stage there was no evidence of PKA localisation. RT-PCR and Western blotting revealed two candidate AKAPs that are known to be targeted to mitochondria, AKAP1 and D-AKAP2. In summary these data show a dynamic regulation of PKA localisation during oocyte and early embryo development.
authors: Department of Physiology, University College London, Gower Street, London, WC1E 6BT, UK. r.webb@sgul.ac.uk
authors: Rachel J
authors: RJ
authors: Webb
authors: Lorna
authors: L
authors: Tinworth
authors: Geraint M H
authors: GM
authors: Thomas
authors: Manuela
authors: M
authors: Zaccolo
authors: John
authors: J
authors: Carroll
mesh_terms: D054758:A Kinase Anchor Proteins / Q000032:analysis / Q000378:metabolism; D000818:Animals; D017868:Cyclic AMP-Dependent Protein Kinases / Q000032:analysis* / Q000378:metabolism; D004622:Embryo, Mammalian / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D005260:Female; D005306:Fertilization; D008540:Meiosis; D051379:Mice; D008928:Mitochondria / Q000737:chemistry; D009865:Oocytes / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D011247:Pregnancy
chemical_list: D054758:A Kinase Anchor Proteins; D017868:Cyclic AMP-Dependent Protein Kinases