Dataset Information

P38-MAPK mediated rRNA processing and translation regulation enables PrE differentiation during mouse blastocyst maturation

ABSTRACT: p38-MAPKs are stress activated kinases necessary for placental development and nutrient and oxygen transfer during murine post-implantation development. In preimplantation development, p38-MAPK activity is required for blastocyst formation. Additionally, we have previously reported its role in regulating specification of inner cell mass (ICM) towards primitive endoderm (PrE), although a comprehensive mechanistic understanding is currently limited. Adopting live embryo imaging, proteomic and transcriptomic approaches, we report experimental data that directly address this deficit. Chemical inhibition of p38-MAPK activity during blastocyst maturation causes impaired blastocyst cavity expansion, most evident between the third and tenth hours post inhibition onset. We identify an overlapping minimal early blastocyst maturation window of p38-MAPKi inhibition (p38-MAPKi) sensitivity, that is sufficient to impair PrE cell fate by the late blastocyst (E4.5) stage. Comparative proteomic analyses reveal substantial downregulation of ribosomal proteins, the mRNA transcripts of which are also significantly upregulated. Ontological analysis of the differentially expressed transcriptome during this developmental period reveals “translation” related gene transcripts as being most significantly, yet transiently, affected by p38-MAPKi. Moreover, combined assays consistently report concomitant reductions in de novo translation that are associated with accumulation of unprocessed rRNA precursors. Using a phospho-proteomic approach, ± p38-MAPKi, to potentially identify p38-MAPK effectors, we report that clonal siRNA mediated knockdown of Mybpp1a, an rRNA transcription and processing regulator gene, is associated with significantly diminished PrE contribution. Lastly, we show that defective PrE specification caused by p38-MAPKi (but not MEK/ERK signalling inhibition) can be partially rescued by activating the archetypal mTOR mediated translation regulatory pathway. Activated p38-MAPK controls blastocyst maturation in an early and distinctly transient developmental window by regulating gene functionalities related to translation, that creates a permissive environment for appropriate specification of ICM cell fate.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Embryo

SUBMITTER: David Potesil

LAB HEAD: Zbynek Zdrahal

PROVIDER: PXD025711 | Pride | 2021-06-28

REPOSITORIES: Pride

ACCESS DATA

Publications

p38-MAPK-mediated translation regulation during early blastocyst development is required for primitive endoderm differentiation in mice.

Bora Pablo P Gahurova Lenka L Mašek Tomáš T Hauserova Andrea A Potěšil David D Jansova Denisa D Susor Andrej A Zdráhal Zbyněk Z Ajduk Anna A Pospíšek Martin M Bruce Alexander W AW

Communications biology 20210625 1

Successful specification of the two mouse blastocyst inner cell mass (ICM) lineages (the primitive endoderm (PrE) and epiblast) is a prerequisite for continued development and requires active fibroblast growth factor 4 (FGF4) signaling. Previously, we identified a role for p38 mitogen-activated protein kinases (p38-MAPKs) during PrE differentiation, but the underlying mechanisms have remained unresolved. Here, we report an early blastocyst window of p38-MAPK activity that is required to regulate ...[more]

PMID: 34172827

Similar Datasets

Project description:p38-MAPKs are stress activated kinases necessary for placental development and nutrient and oxygen transfer during murine post-implantation development. In preimplantation development, p38-MAPK activity is required for blastocyst formation. Additionally, we have previously reported its role in regulating specification of inner cell mass (ICM) towards primitive endoderm (PrE), although a comprehensive mechanistic understanding is currently limited. Adopting live embryo imaging, proteomic and transcriptomic approaches, we report experimental data that directly address this deficit. Chemical inhibition of p38-MAPK activity during blastocyst maturation causes impaired blastocyst cavity expansion, most evident between the third and tenth hours post inhibition onset. We identify an overlapping minimal early blastocyst maturation window of p38-MAPKi inhibition (p38-MAPKi) sensitivity, that is sufficient to impair PrE cell fate by the late blastocyst (E4.5) stage. Comparative proteomic analyses reveal substantial downregulation of ribosomal proteins, the mRNA transcripts of which are also significantly upregulated. Ontological analysis of the differentially expressed transcriptome during this developmental period reveals “translation” related gene transcripts as being most significantly, yet transiently, affected by p38-MAPKi. Moreover, combined assays consistently report concomitant reductions in de novo translation that are associated with accumulation of unprocessed rRNA precursors. Using a phospho-proteomic approach, ± p38-MAPKi, to potentially identify p38-MAPK effectors, we report that clonal siRNA mediated knockdown of Mybpp1a, an rRNA transcription and processing regulator gene, is associated with significantly diminished PrE contribution. Lastly, we show that defective PrE specification caused by p38-MAPKi (but not MEK/ERK signalling inhibition) can be partially rescued by activating the archetypal mTOR mediated translation regulatory pathway.

Project description:2-cell (E1.5) stage embryos were cultured in normal KSOM+AA conditions until E3.5 +2h and thereafter 100 embryos each were moved to control or p38-MAPKi conditions and cultured for another 7 hours (E3.5 +9h). The embryos were then washed through pre-warmed (37˚C) Hank’s balanced salt solution (HBSS, Sigma-Aldrich; Cat. No. H9269) and lysed by moving to a 1.5ml centrifuge tube containing about 15µl of SDT-lysis buffer (4% (w/v) SDS, 100 mM Tris-HCl pH 7.6, 0.1 M DTT). Cell lysis was performed by incubating the tubes in a 95˚C thermoblock for 12 minutes, brief centrifugation at 750 rpm, cooling to room temperature and storage at -80˚C. Individual protein solutions were processed by filter-aided sample preparation (FASP) method with some modifications (see the associated publication for more details). Resulting peptides were cleaned by liquid-liquid extraction (3 iterations) using water saturated ethyl acetate. 1/10th of the FASP eluate was taken out for direct LC-MS measurements, evaporated completely in SpeedVac concentrator (Thermo Fisher Scientific). Peptides were further transferred into LC-MS vials using 50μL of 2.5% formic acid (FA) in 50% acetonitrile (ACN) and 100μL of pure ACN and with addition of polyethylene glycol (final concentration 0.001%) and concentrated in a SpeedVac concentrator. Phosphopeptides were enriched from the remaining 9/10th of the cleaned FASP eluate after complete solvent evaporation (SpeedVac concentrator) using High-Select™ TiO2 Phosphopeptide Enrichment Kit (Thermo Fisher Scientific) according to manufacturer protocol. Phosphopeptide standards (0.1 pmol of MS PhosphoMix 1, 2, 3 Light; Sigma-Aldrich, St. Louis, Missouri, USA) was added to suspended sample in binding/equilibration buffer. Flow-through fraction was dried and used for second enrichment step using High-Select™ Fe-NTA Phosphopeptide Enrichment Kit (Thermo Fisher Scientific, Waltham, Massachusetts, USA) according to manufacturer protocol. Resulting phosphopeptides were extracted into LC-MS vials by 2.5% FA in 50% ACN and 100% ACN with addition of polyethylene glycol (final concentration 0.001%) and concentrated in a SpeedVac concentrator). LC-MS/MS analyses of all peptide mixtures (2 peptide solutions for each sample – 1) not enriched; 2) enriched on phosphopeptides using TiO2 enrichment kit) were done using RSLCnano system connected to Orbitrap Fusion Lumos mass spectrometer (Thermo Fisher Scientific). Prior to LC separation, tryptic digests were online concentrated and desalted using trapping column (100 μm × 30 mm, column compartment temperature of 40˚C) filled with 3.5-μm X-Bridge BEH 130 C18 sorbent (Waters). After washing of trapping column with 0.1% FA, the peptides were eluted (flow rate - 300nl/min) from the trapping column onto an analytical column (Acclaim Pepmap100 C18, 3 µm particles, 75 μm × 500 mm; column compartment temperature of 40˚C, Thermo Fisher Scientific) by using 50 or 100 minutes long nonlinear gradient program (1-56% of mobile phase B; mobile phase A: 0.1% FA in water; mobile phase B: 0.1% FA in 80% ACN) for analysis of phosphopeptide enriched fractions or not enriched peptide mixtures, respectively. Equilibration of the trapping column and the analytical column was done prior to sample injection to sample loop. The analytical column outlet was directly connected to the Digital PicoView 550 (New Objective) ion source with sheath gas option and SilicaTip emitter (New Objective; FS360-20-15-N-20-C12) utilization. ABIRD (ESI Source Solutions) was installed. MS data were acquired in a data-dependent strategy with cycle time for 3 seconds and with survey scan (350-2000 m/z). The resolution of the survey scan was 60000 (200 m/z) with a target value of 4×105 ions and maximum injection time of 50ms. HCD MS/MS (30% relative fragmentation energy, normal mass range) spectra were acquired with a target value of 5.0x104. The MS/MS spectra were recorded in Orbitrap at resolving power of 30,000 or 15,000 (200 m/z) and the maximum injection time for MS/MS was 500 or 22 ms for analysis of phosphopeptides enriched fraction or non-enriched peptide mixture, respectively. Dynamic exclusion was enabled for 60 seconds after one MS/MS spectra acquisition. The isolation window for MS/MS fragmentation was set to 1.6 m/z.

Dataset Information

P38-MAPK mediated rRNA processing and translation regulation enables PrE differentiation during mouse blastocyst maturation

Publications

p38-MAPK-mediated translation regulation during early blastocyst development is required for primitive endoderm differentiation in mice.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure