Nitric Oxide Affects ERK Signaling through Down-Regulation of MAP Kinase Phosphatase Levels during Larval Development of the Ascidian Ciona intestinalis

Abstract

In the ascidian Ciona intestinalis larval development and metamorphosis require a complex interplay of events, including nitric oxide (NO) production, MAP kinases (ERK, JNK) and caspase-3 activation. We have previously shown that NO levels affect the rate of metamorphosis, regulate caspase activity and promote an oxidative stress pathway, resulting in protein nitration. Here, we report that NO down-regulates MAP kinase phosphatases (mkps) expression affecting positively ERK signaling. By pharmacological approach, we observed that the reduction of endogenous NO levels caused a decrease of ERK phosphorylation, whereas increasing levels of NO induced ERK activation. We have also identified the ERK gene network affected by NO, including mpk1, mpk3 and some key developmental genes by quantitative gene expression analysis. We demonstrate that NO induces an ERK-independent down-regulation of mkp1 and mkp3, responsible for maintaining the ERK phosphorylation levels necessary for transcription of key metamorphic genes, such as the hormone receptor rev-erb and the van willebrand protein vwa1c. These results add new insights into the role played by NO during larval development and metamorphosis in Ciona, highlighting the cross-talk between different signaling pathways.

An ancient role for nitric oxide in regulating the animal pelagobenthic life cycle: evidence from a marine sponge

“…We find that NO appears to induce, rather than represses, settlement and metamorphosis as has been observed in some ascidians and molluscs313233. As has been documented in the ascidian Ciona 334464, NO signalling appears to work via – or in concert with – the ERK signalling pathway in A. queenslandica .…”

“…The phylogenetic diversity of taxa in which this has been experimentally observed has led to the proposition that NO maintains larvae in a prepared state for metamorphosis25 and that this role for NO may be a highly conserved feature of marine invertebrate settlement and metamorphosis2930. However, there are documented cases in ascidians and a gastropod of NO playing a positive role in regulating the initiation and rate of metamorphosis31323334, raising the possibility that differing roles of NO may be associated with different animal life histories and ecologies30.…”

Melatonin Contributes to the Seasonality of Multiple Sclerosis Relapses

“…S4h,i). Of note, Erk1/2 inhibition has been previously shown to enhance Th17 cell differentiation (Tan and Lam, 2010) and Erk1/2 phosphorylation has been linked to the reduced expression of REV-ERB proteins (Castellano et al, 2014; Kojetin and Burris, 2014), but the mechanism involved and its relevance for T cells has not been characterized yet. Through a bioinformatic analysis of the nr1d1 promoter we identified a binding site for the CAAT/enhancer-binding protein α (C/EBPα), a leucine zipper transcription factor involved in the regulation of cellular differentiation (Lekstrom-Himes and Xanthopoulos, 1998).…”

From Nitric Oxide Toward S-Nitrosylation: Expanding Roles in Gametes and Embryos

“…Further works had been undertaken in C. intestinalis to unravel the role of NO during larval development. Mitogen-activated Nitric Oxide Synthase -Simple Enzyme-Complex Roles 156 protein kinase (MAPK) and extracellular-regulated kinase (ERK) phosphorylations levels appeared closely related to NO levels [11].…”