JUNO high purity nitrogen plant.

The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kt low level radioactivity liquid scintillator detector in a laboratory 650 m underground. An excellent energy resolution and a large volume offer exciting opportunities for addressing many important topics in neutrino physics. High purity nitrogen is an important factor to ensure the low background of the JUNO detector. High Purity Nitrogen (HPN) is used for detector purging, pipe cleaning, and scintillator purification, among other things in JUNO. According to JUNO's requirements, the radon concentration in HPN should be less than 10 µBq/m3. To meet this requirement, A high-purity nitrogen plant with 100 Nm3/h maximum rate was designed and constructed. Low-temperature adsorption technology is used to remove radioactive impurities in nitrogen. High purification efficiency was ensured by using an activated carbon column with high column height-to-diameter ratio. Electrostatic collection and low-temperature enrichment methods are combined to measure radon in nitrogen. After ten days of continuous operation at 50 Nm3/h flux rate, the plant can to reduce the radon concentration in nitrogen from 37.4±1.8µBq/m3 to less than 1.33 µBq/m3. After HPN with flow rate of 50 Nm3/h passing through low-background pipeline (About 1.3 km), the radon concentration of HPN is 5.6±0.6µBq/m3.

Expression of IZUMO1 and JUNO in the gonads of domestic cats (Felis catus).

Because of the time-consuming nature of surgical neutering and the rapid rate of reproduction among domestic cats, it is crucial to investigate alternative, nonsurgical methods of contraception for this species. Sperm protein IZUMO1 and its oocyte receptor JUNO have been proposed as potential targets for nonsurgical contraceptives. This study aimed to demonstrate (1) the protein coding sequence of feline IZUMO1 and JUNO, (2) gene expression in specific organs by measuring mRNA levels in different visceral tissues, and (3) the expression of IZUMO1 and JUNO during sperm maturation and folliculogenesis, respectively. Amplification for sequencing of feline IZUMO1 and JUNO was performed using the RT-PCR method. Levels of gene expression in different tissues were evaluated using real-time PCR. In situ hybridization was performed to localize JUNO mRNA in ovarian tissues. The complete coding sequences of IZUMO1 and JUNO were obtained and analyzed. A comparison between protein orthologs demonstrated the conservation of IZUMO1 and JUNO in Felidae. The real-time PCR results from various visceral organs indicated that IZUMO1 was significantly higher in the testis than in other organs, whereas JUNO was significantly higher in the ovary than in other organs. Expression of IZUMO1 was found to be higher in the testes than in the caput, corpus, and cauda of epididymides. In situ hybridization revealed that JUNO mRNA was in the ooplasm and nucleus of the primordial, primary, secondary, and antral follicles. Importantly, this was the first study to demonstrate the IZUMO1 and JUNO genes in the testis and ovary of cats. The results are useful for future research related to these genes and for developing contraceptives against these targets.

Positive selection in gamete interaction proteins in Carnivora.

The absence of robust interspecific isolation barriers among pantherines, including the iconic South American jaguar (Panthera onca), led us to study molecular evolution of typically rapidly evolving reproductive proteins within this subfamily and related groups. In this study, we delved into the evolutionary forces acting on the zona pellucida (ZP) gamete interaction protein family and the sperm-oocyte fusion protein pair IZUMO1-JUNO across the Carnivora order, distinguishing between Caniformia and Feliformia suborders and anticipating few significant diversifying changes in the Pantherinae subfamily. A chromosome-resolved jaguar genome assembly facilitated coding sequences, enabling the reconstruction of protein evolutionary histories. Examining sequence variability across more than 30 Carnivora species revealed that Feliformia exhibited significantly lower diversity compared to its sister taxa, Caniformia. Molecular evolution analyses of ZP2 and ZP3, subunits directly involved in sperm-recognition, unveiled diversifying positive selection in Feliformia, Caniformia and Pantherinae, although no significant changes were linked to sperm binding. Structural cross-linking ZP subunits, ZP4 and ZP1 exhibited lower levels or complete absence of positive selection. Notably, the fusion protein IZUMO1 displayed prominent positive selection signatures and sites in basal lineages of both Caniformia and Feliformia, extending along the Caniformia subtree but absent in Pantherinae. Conversely, JUNO did not exhibit any positive selection signatures across tested lineages and clades. Eight Caniformia-specific positive selected sites in IZUMO1 were detected within two JUNO-interaction clusters. Our findings provide for the first time insights into the evolutionary trajectories of ZP proteins and the IZUMO1-JUNO gamete interaction pair within the Carnivora order.

Sperm induction of somatic cell-cell fusion as a novel functional test.

The fusion of mammalian gametes requires the interaction between IZUMO1 on the sperm and JUNO on the oocyte. We have recently shown that ectopic expression of mouse IZUMO1 induces cell-cell fusion and that sperm can fuse to fibroblasts expressing JUNO. Here, we found that the incubation of mouse sperm with hamster fibroblasts or human epithelial cells in culture induces the fusion between these somatic cells and the formation of syncytia, a pattern previously observed with some animal viruses. This sperm-induced cell-cell fusion requires a species-matching JUNO on both fusing cells, can be blocked by an antibody against IZUMO1, and does not rely on the synthesis of new proteins. The fusion is dependent on the sperm's fusogenic capacity, making this a reliable, fast, and simple method for predicting sperm function during the diagnosis of male infertility.

Juno and CD9 protein network organization in oolemma of mouse oocyte.

Juno and CD9 protein, expressed in oolemma, are known to be essential for sperm-oocyte binding and fusion. Although evidence exists that these two proteins cooperate, their interaction has not yet been demonstrated. Here in, we present Juno and CD9 mutual localization over the surface of mouse metaphase II oocytes captured using the 3D STED super-resolution technique. The precise localization of examined proteins was identified in different compartments of oolemma such as the microvillar membrane, planar membrane between individual microvilli, and the membrane of microvilli-free region. Observed variance in localization of Juno and CD9 was confirmed by analysis of transmission and scanning electron microscopy images, which showed a significant difference in the presence of proteins between selected membrane compartments. Colocalization analysis of super-resolution images based on Pearson's correlation coefficient supported evidence of Juno and CD9 mutual position in the oolemma, which was identified by proximity ligation assay. Importantly, the interaction between Juno and CD9 was detected by co-immunoprecipitation and mass spectrometry in HEK293T/17 transfected cell line. For better understanding of experimental data, mouse Juno and CD9 3D structure were prepared by comparative homology modelling and several protein-protein flexible sidechain dockings were performed using the ClusPro server. The dynamic state of the proteins was studied in real-time at atomic level by molecular dynamics (MD) simulation. Docking and MD simulation predicted Juno-CD9 interactions and stability also suggesting an interactive mechanism. Using the multiscale approach, we detected close proximity of Juno and CD9 within microvillar oolemma however, not in the planar membrane or microvilli-free region. Our findings show yet unidentified Juno and CD9 interaction within the mouse oolemma protein network prior to sperm attachment. These results suggest that a Juno and CD9 interactive network could assist in primary Juno binding to sperm Izumo1 as a prerequisite to subsequent gamete membrane fusion.

Study on the expression patterns and function of JUNO and CD9 in bovine oocytes during in vitro maturation.

Fertilization proteins JUNO and CD9 play vital roles in sperm-egg fusion, but little is known about their expression patterns during in vitro maturation (IVM) and their function during in vitro fertilization (IVF) of bovine oocytes. In this study, qRT-PCR and immunofluorescence staining were used to detect the mRNA and protein expression levels of JUNO and CD9 genes in bovine oocytes and cumulus cells. Then, fertilization rate of MII oocytes treated with (i) JUNO antibody (1, 5 and 25 µg/ml) or (ii) CD9 antibody (1, 5 and 25 µg/ml) or (iii) CD9 antibody (5 µg/ml) + JUNO antibody (5 µg/ml) were recorded. Our results showed that the mRNA and protein expression levels of JUNO and CD9 genes significantly increased from bovine GV oocytes to MII oocytes, and similar mRNA expression patterns of JUNO and CD9 were also detected in cumulus cells. All groups of oocytes treated with CD9 antibody or JUNO antibody showed significantly decreased fertilization rates (p < .05). Particularly, the fertilization ability of oocytes treated with CD9 antibody (5 µg/ml) + JUNO antibody (5 µg/ml) sharply decreased to 3.48 ± 0.11%. In conclusion, our study revealed the expression levels of JUNO and CD9 genes in oocytes and cumulus cells increased during IVM of bovine oocytes, with JUNO protein playing a major role in the fertilization of bovine oocytes.

Jupiter's Low-Altitude Auroral Zones: Fields, Particles, Plasma Waves, and Density Depletions.

The Juno spacecraft's polar orbits have enabled direct sampling of Jupiter's low-altitude auroral field lines. While various data sets have identified unique features over Jupiter's main aurora, they are yet to be analyzed altogether to determine how they can be reconciled and fit into the bigger picture of Jupiter's auroral generation mechanisms. Jupiter's main aurora has been classified into distinct "zones", based on repeatable signatures found in energetic electron and proton spectra. We combine fields, particles, and plasma wave data sets to analyze Zone-I and Zone-II, which are suggested to carry upward and downward field-aligned currents, respectively. We find Zone-I to have well-defined boundaries across all data sets. H+ and/or H3 + cyclotron waves are commonly observed in Zone-I in the presence of energetic upward H+ beams and downward energetic electron beams. Zone-II, on the other hand, does not have a clear poleward boundary with the polar cap, and its signatures are more sporadic. Large-amplitude solitary waves, which are reminiscent of those ubiquitous in Earth's downward current region, are a key feature of Zone-II. Alfvénic fluctuations are most prominent in the diffuse aurora and are repeatedly found to diminish in Zone-I and Zone-II, likely due to dissipation, at higher altitudes, to energize auroral electrons. Finally, we identify significant electron density depletions, by up to 2 orders of magnitude, in Zone-I, and discuss their important implications for the development of parallel potentials, Alfvénic dissipation, and radio wave generation.

Properties of Ion-Inertial Scale Plasmoids Observed by the Juno Spacecraft in the Jovian Magnetotail.

We expand on previous observations of magnetic reconnection in Jupiter's magnetosphere by constructing a survey of ion-inertial scale plasmoids in the Jovian magnetotail. We developed an automated detection algorithm to identify reversals in the B θ component and performed the minimum variance analysis for each identified plasmoid to characterize its helical structure. The magnetic field observations were complemented by data collected using the Juno Waves instrument, which is used to estimate the total electron density, and the JEDI energetic particle detectors. We identified 87 plasmoids with "peak-to-peak" durations between 10 and 300 s. Thirty-one plasmoids possessed a core field and were classified as flux-ropes. The other 56 plasmoids had minimum field strength at their centers and were termed O-lines. Out of the 87 plasmoids, 58 had in situ signatures shorter than 60 s, despite the algorithm's upper limit being 300 s, suggesting that smaller plasmoids with shorter durations were more likely to be detected by Juno. We estimate the diameter of these plasmoids assuming a circular cross section and a travel speed equal to the Alfven speed in the surrounding lobes. Using the electron density inferred by Waves, we contend that these plasmoid diameters were within an order of the local ion-inertial length. Our results demonstrate that magnetic reconnection in the Jovian magnetotail occurs at ion scales like in other space environments. We show that ion-scale plasmoids would need to be released every 0.1 s or less to match the canonical 1 ton/s rate of plasma production due to Io.

In silico Docking Analysis for Blocking JUNO-IZUMO1 Interaction Identifies Two Small Molecules that Block in vitro Fertilization.

Combined hormone drugs are the basis for orally administered contraception. However, they are associated with severe side effects that are even more impactful for women in developing countries, where resources are limited. The risk of side effects may be reduced by non-hormonal small molecules which specifically target proteins involved in fertilization. In this study, we present a virtual docking experiment directed to discover molecules that target the crucial fertilization interactions of JUNO (oocyte) and IZUMO1 (sperm). We docked 913,000 molecules to two crystal structures of JUNO and ranked them on the basis of energy-related criteria. Of the 32 tested candidates, two molecules (i.e., Z786028994 and Z1290281203) demonstrated fertilization inhibitory effect in both an in vitro fertilization (IVF) assay in mice and an in vitro penetration of human sperm into hamster oocytes. Despite this clear effect on fertilization, these two molecules did not show JUNO-IZUMO1 interaction blocking activity as assessed by AVidity-based EXtracellular Interaction Screening (AVEXIS). Therefore, further research is required to determine the mechanism of action of these two fertilization inhibitors.

Molecular Epidemiology of Group B Streptococcus Colonization in Egyptian Women.

(1) Background: Streptococcus agalactiae or Group B Streptococcus (GBS) causes severe neonatal infections with a high burden of disease, especially in Africa. Maternal vaginal colonization and perinatal transmissions represent the common mode of acquiring the infection. Development of an effective maternal vaccine against GBS relies on molecular surveillance of the maternal GBS population to better understand the global distribution of GBS clones and serotypes. (2) Methods: Here, we present genomic data from a collection of colonizing GBS strains from Ismailia, Egypt that were sequenced and characterized within the global JUNO project. (3) Results: A large proportion of serotype VI, ST14 strains was discovered, a serotype which is rarely found in strain collections from the US and Europe and typically not included in the current vaccine formulations. (4) Conclusions: The molecular epidemiology of these strains clearly points to the African origin with the detection of several sequence types (STs) that have only been observed in Africa. Our data underline the importance of continuous molecular surveillance of the GBS population for future vaccine implementations.

Juno's Close Encounter With Ganymede-An Overview.

The Juno spacecraft has been in orbit around Jupiter since 2016. Two flybys of Ganymede were executed in 2021, opportunities realized by evolution of Juno's polar orbit over the intervening 5 years. The geometry of the close flyby just prior to the 34th perijove pass by Jupiter brought the spacecraft inside Ganymede's unique magnetosphere. Juno's payload, designed to study Jupiter's magnetosphere, had ample dynamic range to study Ganymede's magnetosphere. The Juno radio system was used both for gravity measurements and for study of Ganymede's ionosphere. Remote sensing of Ganymede returned new results on geology, surface composition, and thermal properties of the surface and subsurface.

Juno Plasma Wave Observations at Ganymede.

The Juno Waves instrument measured plasma waves associated with Ganymede's magnetosphere during its flyby on 7 June, day 158, 2021. Three distinct regions were identified including a wake, and nightside and dayside regions in the magnetosphere distinguished by their electron densities and associated variability. The magnetosphere includes electron cyclotron harmonic emissions including a band at the upper hybrid frequency, as well as whistler-mode chorus and hiss. These waves likely interact with energetic electrons in Ganymede's magnetosphere by pitch angle scattering and/or accelerating the electrons. The wake is accentuated by low-frequency turbulence and electrostatic solitary waves. Radio emissions observed before and after the flyby likely have their source in Ganymede's magnetosphere.

Ganymede Observations by JunoCam on Juno Perijove 34.

During the Juno Mission's encounter with Ganymede on 7 June 2021, the Juno camera (JunoCam) acquired four images of Ganymede in color. These images covered one-sixth of Ganymede at scales from 840 m to ∼4 km/pixel. Most of this area was only previously imaged by Voyager 1 in 1979, at lower spatial resolution and poorer image quality. No changes were observed over this area of Ganymede in the 42 years since Voyager. JunoCam provided overlapping coverage, from which we developed a digital elevation model of the best-resolved area. A 3 km high dome at the subjovian point was confirmed, 450 km by 750 km. We used the JunoCam images to refine the geologic map of Ganymede in eastern Perrine Regio.

Improvement of Fertilization Capacity and Developmental Ability of Vitrified Bovine Oocytes by JUNO mRNA Microinjection and Cholesterol-Loaded Methyl-ß-Cyclodextrin Treatment.

Vitrification of oocytes is crucial for embryo biotechnologies, germplasm cryopreservation of endangered and excellent female animals, and the fertility of humans. However, vitrification significantly impairs the fertilization ability of oocytes, which significantly limits its widely used application. JUNO protein, a receptor for Izumo1, is involved in sperm-oocyte fusion and is an indispensable protein for mammalian fertilization, and its abundance is susceptible to vitrification. However, it is still unclear how vitrification reduces the fertilization capacity of bovine oocytes by affecting JUNO protein. This study was designed to investigate the effect of vitrification on the abundance and post-translational modifications of JUNO protein in bovine oocytes. Our results showed that vitrification did not alter the amino acid sequence of JUNO protein in bovine oocytes. Furthermore, the liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis results showed that vitrification significantly reduced the number and changed the location of disulfide bonds, and increased the number of both phosphorylation and glycosylation sites of JUNO protein in bovine oocytes. Finally, the fertilization capacity and development ability of vitrified oocytes treated with 200 pg JUNO mRNA microinjection and cholesterol-loaded methyl-ß-cyclodextrin (CLC/MßCD) were similar to those of fresh oocytes. In conclusion, our results showed that vitrification of bovine oocytes did not alter the protein sequence of JUNO, but induced post-translational modifications and changed protein abundance. Moreover, the fertilization and development ability of vitrified bovine oocytes were improved by the combination treatment of JUNO mRNA microinjection and CLC/MßCD.

Oolemma Receptors in Mammalian Molecular Fertilization: Function and New Methods of Study.

Fertilization is a key process in biology to the extent that a new individual will be born from the fusion of two cells, one of which leaves the organism in which it was produced to exert its function within a different organism. The structure and function of gametes, and main aspects of fertilization are well known. However, we have limited knowledge about the specific molecules participating in each of the steps of the fertilization process due to the transient nature of gamete interaction. Moreover, if we specifically focus in the fusion of both gametes' membrane, we might say our molecular knowledge is practically null, despite that molecular mechanisms of cell-to-cell adhesion are well studied in somatic cells. Moreover, between both gametes, the molecular knowledge in the egg is even scarcer than in the spermatozoon for different reasons addressed in this review. Sperm-specific protein IZUMO1 and its oocyte partner, JUNO, are the first cell surface receptor pair essential for sperm-egg plasma membrane binding. Recently, thanks to gene editing tools and the development and validation of in vitro models, new oocyte molecules are being suggested in gamete fusion such as phosphatidylserine recognition receptors. Undoubtedly, we are in a new era for widening our comprehension on molecular fertilization. In this work, we comprehensively address the proposed molecules involved in gamete binding and fusion, from the oocyte perspective, and the new methods that are providing a better understanding of these crucial molecules.

2,4-DCP compromises the fertilization capacity of mouse oocytes.

2,4-DCP (2,4-dichlorophenol) is an environmental estrogen that is ubiquitously distributed in the environment and widely used to produce herbicides and pharmaceutical intermediates. Although 2,4-DCP is suspected to have endocrine disruption, the reproductive toxicity of 2,4-DCP in mammals has not been adequately assessed. In the present study, we examined the effect of 2,4-DCP on the fertility of mouse eggs. The data showed that oral administration of 2,4-DCP (180 mg/kg/day for 7 days) compromises the fertilization rate of mouse oocytes. To further analyze the mechanism by which 2,4-DCP decreases fertilization, the key regulators and events during fertilization of mouse eggs were investigated. We found that the dynamics of cortical granules (CGs) were disrupted by showing the redistribution of CG free domain in 2,4-DCP-administered oocytes. This abnormality perturbed the sperm binding site in the zona pellucida (ZP) and dramatically reduced the number of sperm binding to the ZP of 2,4-DCP-administered oocytes. In addition, the abundance of Juno, a sperm receptor on the egg membrane, was also decreased and its distribution was mislocated in 2,4-DCP-administered oocytes. Finally, we validated that the defects of fertilization participants and events caused by 2,4-DCP might be mediated by the increased level of reactive oxygen species-induced apoptosis of oocytes. Therefore, we demonstrate that 2,4-DCP compromises the fertilization ability of mouse oocytes via inducing oxidative stress.

Expression, structure and function analysis of the sperm-oocyte fusion genes Juno and Izumo1 in sheep (Ovis aries).

BACKGROUND: JUNO and IZUMO1 are the first receptor-ligand protein pairs discovered to be essential for sperm-oocyte fusion; their interaction is indispensable for fertilization. METHODS: PCR was used to clone the full-length DNA sequence of the Juno gene in sheep. The single nucleotide polymorphism (SNP) loci of Juno were genotyped by Sequenom MassARRAY®. PCR combined with rapid amplification of cDNA Ends were used to clone the full-length cDNA sequence of Juno and Izumo1. Reverse transcriptase-PCR (RT-PCR) and real time-quantitative-PCR (RT-qPCR) were used to analyze the genes' expression in tissues of sheep, and single cell RNA-seq was used to analyze the genes' expression in oocytes, granulosa cells and follicular theca of polytocous and monotocous Small Tail Han ewes. Bioinformatics was used to analyze advanced structure and phylogeny of JUNO and IZUMO1 proteins. RESULTS: The full-length DNA sequence of the Juno gene in sheep was cloned and nine SNPs were screened. We found a significant association between the g.848253 C > A locus of Juno and litter size of Small Tail Han sheep (P < 0.05). The full-length cDNA sequence of Juno and Izumo1 genes from Small Tail Han sheep were obtained. We found a new segment of the Izumo1 CDS consisting of 35 bp, and we confirmed the Izumo1 gene has 9 exons, not 8. RT-qPCR showed that Juno and Izumo1 genes were highly expressed in ovarian and testicular tissues, respectively (P < 0.01). Single cell RNA-seq showed Juno was specifically expressed in oocytes, but not in granulosa cells or follicular theca, while Izumo1 displayed little to no expression in all three cell types. There was no difference in expression of the Juno gene in oocyte and ovarian tissue in sheep with different litter sizes, indicating expression of Juno is not related to litter size traits. Bioinformatic analysis revealed the g.848253 C > A locus of Juno results in a nonconservative missense point mutation leading to a change from Phe to Leu at position 219 in the amino acid sequence. CONCLUSIONS: For the first time, this study systematically analyzed the expression, structure and function of Juno and Izumo1 genes and their encoded proteins in Small Tail Han sheep, providing the basis for future studies of the regulatory mechanisms of Juno and Izumo1 genes.

The combination treatment of cholesterol-loaded methyl-ß-cyclodextrin and methyl-ß-cyclodextrin significantly improves the fertilization capacity of vitrified bovine oocytes by protecting fertilization protein JUNO.

Many experiments show that vitrification significantly reduces the fertilization capacity of mammalian oocytes, restricting the application of vitrified oocytes. It has been proven that the JUNO protein plays a vital role in mammalian oocytes fertilization. However, little information is available about the effects of vitrification on the JUNO protein and the procedure to protect it in bovine oocytes. Here, the present study was designed to investigate the effect of vitrification on the JUNO protein level in bovine oocytes. In this study, MII oocytes were treated with cholesterol-loaded methyl-ß-cyclodextrin (CLC; 0, 10, 15, 20 mM) for 45 min before vitrification and methyl-ß-cyclodextrin (MßCD; 0, 2.25, 4.25, 6.25 mM) for 45 min after thawing (38-39°C). Then, the expression level and function of JUNO protein, cholesterol level in the membrane, the externalization of phosphatidylserine, sperm binding capacity and the developmental ability of vitrified bovine oocytes were examined. Our results showed that vitrification significantly decreased the JUNO protein level, cholesterol level, sperm binding capacity, development ability, and increased the promoter methylation level of the JUNO gene and apoptosis level of bovine oocytes. Furthermore, 15 mM CLC + 4.25 mM MßCD treatment significantly improved the cholesterol level and increased sperm binding and development ability of vitrified bovine oocytes. In conclusion, the combination treatment of cholesterol-loaded methyl-ß-cyclodextrin and methyl-ß-cyclodextrin significantly improves the fertilization capacity of vitrified bovine oocytes by protecting fertilization protein JUNO.

Sperm IZUMO1 Is Required for Binding Preceding Fusion With Oolemma in Mice and Rats.

Fertilization occurs as the culmination of multi-step complex processes. First, mammalian spermatozoa undergo the acrosome reaction to become fusion-competent. Then, the acrosome-reacted spermatozoa penetrate the zona pellucida and adhere to and finally fuse with the egg plasma membrane. IZUMO1 is the first sperm protein proven to be essential for sperm-egg fusion in mammals, as Izumo1 knockout mouse spermatozoa adhere to but fail to fuse with the oolemma. However, the IZUMO1 function in other species remains largely unknown. Here, we generated Izumo1 knockout rats by CRISPR/Cas9 and found the male rats were infertile. Unlike in mice, Izumo1 knockout rat spermatozoa failed to bind to the oolemma. Further investigation revealed that the acrosome-intact sperm binding conceals a decreased number of the acrosome-reacted sperm bound to the oolemma in Izumo1 knockout mice. Of note, we could not see any apparent defects in the binding of the acrosome-reacted sperm to the oolemma in the mice lacking recently found fusion-indispensable genes, Fimp, Sof1, Spaca6, or Tmem95. Collectively, our data suggest that IZUMO1 is required for the sperm-oolemma binding prior to fusion at least in rat.

A Preliminary Study of Magnetosphere-Ionosphere-Thermosphere Coupling at Jupiter: Juno Multi-Instrument Measurements and Modeling Tools.

The dynamics of the Jovian magnetosphere are controlled by the interplay of the planet's fast rotation, its main iogenic plasma source and its interaction with the solar wind. Magnetosphere-Ionosphere-Thermosphere (MIT) coupling processes controlling this interplay are significantly different from their Earth and Saturn counterparts. At the ionospheric level, they can be characterized by a set of key parameters: ionospheric conductances, electric currents and fields, exchanges of particles along field lines, Joule heating and particle energy deposition. From these parameters, one can determine (a) how magnetospheric currents close into the ionosphere, and (b) the net deposition/extraction of energy into/out of the upper atmosphere associated to MIT coupling. We present a new method combining Juno multi-instrument data (MAG, JADE, JEDI, UVS, JIRAM and Waves) and modeling tools to estimate these key parameters along Juno's trajectories. We first apply this method to two southern hemisphere main auroral oval crossings to illustrate how the coupling parameters are derived. We then present a preliminary statistical analysis of the morphology and amplitudes of these key parameters for eight among the first nine southern perijoves. We aim to extend our method to more Juno orbits to progressively build a comprehensive view of Jovian MIT coupling at the level of the main auroral oval.