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Abstract Context Primary ovarian insufficiency (POI) is a frequently occurring disorder affecting approximately 1% of women under 40 years of age. POI, which is characterized by the premature depletion of ovarian follicles and elevated plasma levels of follicle-stimulating hormone, leads to infertility. Although various etiological factors have been described, including chromosomal abnormalities and gene mutations, most cases remain idiopathic. Objective To identify and to functionally validate new sequence variants in 2 genes that play a key role in mammalian ovarian function, BMPR1A and BMPR1B (encoding for bone morphogenic protein receptor), leading to POI. Methods The impact on bone morphogenic protein (BMP) signaling of BMPR1A and BMPR1B variants, previously identified by whole-exome sequencing on 69 women affected by isolated POI, was established by different in vitro functional experiments. Results We demonstrate that the BMPR1A-p.Arg442His and BMPR1B-p.Phe272Leu variants are correctly expressed and located but lead to an impairment of downstream BMP signaling. Conclusion In accordance with infertility observed in mice lacking Bmpr1a in the ovaries and in Bmpr1b-/- mice, our results unveil, for the first time, a link between BMPR1A and BMPR1B variants and the origin of POI. We show that BMP signaling impairment through specific BMPR1A and BMPR1B variants is a novel pathophysiological mechanism involved in human POI. We consider that BMPR1A and BMPR1B variants constitute genetic biomarkers of the origin of POI and have clinical utility.

Abstract Context Determination of steroid levels in the amniotic fluid gives some insight on fetal adrenal and gonadal functions. Objective Our objectives were to establish reference ranges of 12 steroid levels throughout pregnancy and to compare them with steroid levels from pregnancies with fetuses presenting with 21-hydroxylase deficiency (21OHD). Methods Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was applied to 145 “control” amniotic fluid samples from gynecology activity (12 + 6 to 32 + 4 gestational weeks, GW). The following steroids were analyzed according to gestational age and compared to 23 amniotic fluid samples from fetuses with classic 21OHD confirmed by molecular studies: delta-4-androstenedione (D4), dehydroepiandrosterone (DHEA), 17-hydroxyprogesterone (17OHP), 11-deoxycortisol (11OH), 21-deoxycortisol (21OH), corticosterone, deoxycorticosterone (DOC), testosterone, pregnenolone, 17-hydroxypregnenolone (17Pregn), cortisol, and cortisone. Chromosomal sex was determined by karyotype and gestational age by biometric measurements. Results Analysis of control samples showed a statistically significant difference for D4 and testosterone levels according to fetal sex. Cortisol, corticosterone, and DOC had lower concentrations before 20 GW than after 20 GW, whereas 17Pregn and pregnenolone had higher concentrations before 20 GW. This allowed us to establish age- and sex-dependent reference values. We observed higher 21OH, 17Pregn, D4, and testosterone levels in females with 21OHD than female controls. The ratios 17OHP/17Pregn, D4/DHEA, and 11OH/17OHP appeared discriminant for the diagnosis of 21OHD. Conclusion Our study provides information on fetal steroidogenesis and suggests reference values for 12 steroids during pregnancy. This allows a prenatal diagnosis of 21OHD within 24 hours and might be useful in the diagnosis of other variations of sex development.

Primary ovarian insufficiency (POI) is a major cause of infertility. This disease is characterized by amenorrhea with an increase in gonadotropin levels and affects 1% of women before the age of 40. POI may be the result of a broad spectrum of disorders caused by two main mechanisms: abnormal follicular development and follicle depletion due to a defect in their formation or an aberrantly rapid depletion of the stock. Although the majority of cases are idiopathic, POI can be trigged by autoimmune disease, infectious agents, iatrogenic effects, or genetic causes. It may also be part of syndromic diseases such as Turner, Fragile-X or Blepharophimosis Ptosis Epicanthus Inversus syndrome. However, in the majority of cases, the cause of POI is unknown suggesting that new causative genes are yet to be discovered. We conducted a Whole Exome Sequencing on 69 Caucasian women with sporadic POI and performed a bioinformatics analysis on a specific subset of 420 coherent candidate genes1. We identified variations in about fifty genes potentially linked to POI, including new genes never described to be associated with the diseases aetiology, such as AuTophagy related Genes (ATG)2, KHDRBS1 gene encoding an RNA-binding protein3, NOTCH2 gene4... We also found variants in genes encoding Bone Morphogenetic Protein Receptors (BMPR1A and BMPR1B) in three patients. These receptors bind ligands of TGFβ superfamily. Mutations of members of this family (e.g. BMP15, GDF9) are known to be involved in the etiology of POI. BMPR encode transmembrane receptors with serine-threonine kinase activity expressed in the granulosa cells of growing follicles. Missense variations, located in the kinase domain of both receptors 1A and 1B, are predicted to be deleterious in silico. We studied the signaling pathway of these receptors: SMAD proteins phosphorylation, measurement of their transcriptional activity and expression of specific target genes and showed that they are deleterious. Bmpr1a -/- and Bmpr1b-/- mouse models develop infertility due to a reduced spontaneous ovulation and compromised cumulus expansion respectively, indicating that both genes play a crucial role in fertility. Altogether, our study describes the first BMPR1A and 1B mutations associated with POI and increases the number of genes formally implicated as being responsible for this condition. 1Patiño LC, Beau I, Carlosama C, Buitrago JC, González R, Suárez CF, Patarroyo MA, Delemer B, Young J, Binart N, Laissue P. Hum Reprod. 2017; 32(7):1512-1520. 2Delcour C, Amazit L, Patino L, Magnin F, Fagart J, Delemer B, Young J, Laissue P, Binart N, Beau I. Genet Med. 2018 (in press) 3Carlosama C, Patiño L, Beau I, Morel A, Delemer B, Young J, Binart N, Laissue P. Clin Endocrinol (Oxf). 2018 (in press) 4Patiño LC, Beau I, Morel A, Delemer B, Young J, Binart N, Laissue P. Hum Mutat. 2018 (in press)

Lignin, one of the most abundant biopolymers on Earth, derives from the plant phenolic metabolism. It appeared upon terrestrialization and is thought critical for plant colonization of land. Early diverging land plants do not form lignin, but already have elements of its biosynthetic machinery. Here we delete in a moss the P450 oxygenase that defines the entry point in angiosperm lignin metabolism, and find that its pre-lignin pathway is essential for development. This pathway does not involve biochemical regulation via shikimate coupling, but instead is coupled with ascorbate catabolism, and controls the synthesis of the moss cuticle, which prevents desiccation and organ fusion. These cuticles share common features with lignin, cutin and suberin, and may represent the extant representative of a common ancestor. Our results demonstrate a critical role for the ancestral phenolic metabolism in moss erect growth and cuticle permeability, consistent with importance in plant adaptation to terrestrial conditions. The phenolic polymer lignin is thought to have contributed to adaptation of early land plants to terrestrial environments. Here Renault et al . show that moss, which does not produce lignin, contains an ancestral phenolic metabolism pathway that produces a phenol-enriched cuticle and prevents desiccation.

X-ray photoelectron spectroscopy of bovine serum albumin (BSA) in a liquid jet is used to investigate the electronic structure of a solvated protein, yielding insight into charge transfer mechanisms in biological systems in their natural environment. No structural damage was observed in BSA following X-ray photoelectron spectroscopy in a liquid jet sample environment. Carbon and nitrogen atoms in different chemical environments were resolved in the X-ray photoelectron spectra of both solid and solvated BSA. The calculations of charge distributions demonstrate the difficulty of assigning chemical contributions in complex systems in an aqueous environment. The high-resolution X-ray core electron spectra recorded are unchanged upon solvation. A comparison of the valence bands of BSA in both phases is also presented. These bands display a higher sensitivity to solvation effects. The ionization energy of the solvated BSA is determined at 5.7 ± 0.3 eV. Experimental results are compared with theoretical calculations to distinguish the contributions of various molecular components to the electronic structure. This comparison points towards the role of water in hole delocalization in proteins.

The bevacizumab (bev)/olaparib (ola) maintenance regimen was approved for BRCA1/2 -mutated (BRCAmut) and Homologous Recombination Deficient (HRD) high-grade Advanced Ovarian Cancer (AOC) first line setting, based on a significantly improved progression-free survival (PFS) compared to bev alone in the PAOLA-1/ENGOT-ov25 trial (NCT02477644), where HRD was detected by MyChoice CDx PLUS test. The academic shallowHRDv2 test was developed based on shallow whole-genome sequencing as an alternative to MyChoice. Analytical and clinical validities of shallowHRDv2 as compared to MyChoice on 449 PAOLA-1 tumor samples are presented. The overall agreement between shallowHRDv2 and MyChoice was 94% (369/394). Less non-contributive tests were observed with shallowHRDv2 (15/449; 3%) than with MyChoice (51/449; 11%). Patients with HRD tumors according to shallowHRDv2 (including BRCAmut) showed a significantly prolonged PFS with bev+ola versus bev (median PFS: 65.7 versus 20.3 months, hazard ratio (HR): 0.36 [95% CI: 0.24–0.53]). This benefit was significant also for BRCA1/2 wild-type tumors (40.8 versus 19.5 months, HR: 0.45 [95% CI: 0.26–0.76]). ShallowHRDv2 is a performant, clinically validated, and cost-effective test for HRD detection.

The growth hormone secretagogue receptor (GHSR) and dopamine receptor (D2R) have been shown to oligomerize in hypothalamic neurons with a significant effect on dopamine signaling, but the molecular processes underlying this effect are still obscure. We used here the purified GHSR and D2R to establish that these two receptors assemble in a lipid environment as a tetrameric complex composed of two each of the receptors. This complex further recruits G proteins to give rise to an assembly with only two G protein trimers bound to a receptor tetramer. We further demonstrate that receptor heteromerization directly impacts on dopamine-mediated Gi protein activation by modulating the conformation of its α-subunit. Indeed, association to the purified GHSR:D2R heteromer triggers a different active conformation of Gαi that is linked to a higher rate of GTP binding and a faster dissociation from the heteromeric receptor. This is an additional mechanism to expand the repertoire of GPCR signaling modulation that could have implications for the control of dopamine signaling in normal and physiopathological conditions.

We have developed a magnetic bottle time-of-flight electron-electron coincidence spectrometer to perform measurements on solvated molecules in a liquid micro-jet. We present here the first results obtained after ionization of the oxygen 1 s inner-shell of sodium benzoate molecules and show the possibilities to filter out the electron signal arising from the liquid phase from the signal of water molecules in the gas phase. Both photoelectrons and Auger electrons spectra (unfiltered and filtered) are presented.

Significance G protein-coupled receptors (GPCRs) are one of the largest cell surface receptor family that transmit their signal through coupling to intracellular partners, such as G proteins. Receptor oligomerization has been shown to be pivotal in this signaling process. To address how oligomerization can impact on signaling in a major physiological process, dopamine signaling, we used a purified GPCR heteromer composed of the ghrelin and dopamine receptors to which we applied a variety of state-of-the-art biochemical and biophysical approaches. By doing so, we provide a direct experimental evidence for a mechanism where receptor heteromerization affects the conformation of the associated G protein. This sheds light on the way a GPCR oligomer can affect G protein activation to modulate signaling.

The phenylpropanoid pathway is a plant metabolism intimately linked to the transition to terrestrial life. It produces phenolic compounds that play essential roles in stress mitigation and ecological interactions. The pathway also provides the building blocks for hydrophobic polymers that form apoplastic diffusion barriers and make up a significant fraction of the land plant biomass. Despite its significance in embryophytes (i.e., land plants), the origin and evolutionary history of the phenylpropanoid pathway remain poorly understood. In particular, little is known about the organization and function of the pathway in bryophytes, the non-vascular embryophytes. In this study, we conducted a multidisciplinary analysis of the CYP73 gene family that encodes t-cinnamic acid 4-hydroxylase (C4H), the first plant-specific enzyme in the pathway. Our results indicate that C4H activity originated with the emergence of the CYP73 gene family in an ancestor of land plants and was supported by an arginine residue that stabilizes its substrate in the active site. C4H deficiency in the moss Physcomitrium patens, the liverwort Marchantia polymorpha and the hornwort Anthoceros agrestis resulted in a shortage of phenylpropanoids and abnormal plant development. The latter could be rescued in the moss by the exogenous supply of p-coumaric acid, the product of C4H. Our findings establish the emergence of the CYP73 gene family as a foundational event for the development of the canonical plant phenylpropanoid pathway and underscores the deep-rooted conservation of the C4H enzyme function in embryophyte biology.