SMC2 ablation impairs bovine embryo development shortly after blastocyst hatching.

In Brief: Bovine embryos lacking SMC2 (a core component of condensins I and II) are unable to survive maternal recognition of pregnancy. SMC2 KO embryos are able to form blastocysts, exhibiting a reduced cell proliferation ability, and arrest their development shortly after hatching.

Abstract: Condensins are large protein complexes required for chromosome assembly and segregation during mitosis and meiosis.

Magnetic-Assisted Control of Eggs and Embryos via Zona Pellucida-Linked Nanoparticles.

Eggs and embryo manipulation is an important biotechnological challenge to enable positioning, entrapment, and selection of reproductive cells to advance into a new era of nature-like assisted reproductive technologies. Oviductin (OVGP1) is an abundant protein in the oviduct that binds reversibly to the zona pellucida, an extracellular matrix that surrounds eggs and embryos. Here, the study reports a new method coupling OVGP1 to magnetic nanoparticles (NP) forming a complex (NPOv).

Sperm-Binding Assay Using an In Vitro 3D Model of the Mammalian Cumulus-Oocyte Complex.

We have recently described a new model to study gamete interaction in mammalian species. The model recreates the spherical surface of the oocyte by using magnetic Sepharose beads coated with a layer of a recombinant protein involved in gamete interaction (such as ZP2, or the IZUMO1 receptor JUNO) and an external layer of cumulus oophorus cells, thus mimicking, to some extent, a native cumulus-oocyte complex. Once generated, this 3D model can be used in a sperm-binding assay to obtain valuable information about the molecular basis of gamete interaction, since different recombinant proteins can be used to coat the bead surface, thus generating a variety of models to be used for several species.

Sperm binding to ZP2-coated beads improve the efficiency of porcine in vitro fertilisation.

The role of specific zona pellucida (ZP) glycoproteins in gamete interaction has not yet been elucidated in many species. A recently developed 3D model based on magnetic sepharose beads (B) conjugated to recombinant ZP glycoproteins (BZP) and cumulus cells (CBZP) allows the study of isolated ZP proteins in gamete recognition studies. The objective of this work was to study the role of porcine ZP2, ZP3 and ZP4 proteins in sperm binding, cumulus cell adhesion and acrosome reaction triggering.

JUNO protein coated beads: A potential tool to predict bovine sperm fertilizing ability.

Considerable variation in fertility exists between bulls in AI centres, despite passing minimum post-thaw quality control checks. The development of a reliable in vitro test to predict bull fertility could enable the identification and selection of high fertility bulls, without the need to resort to test inseminations. An in-depth knowledge of the molecular basis of fertilization is a prerequisite to the development of such a test or combination of tests.

Mammalian spermatozoa and cumulus cells bind to a 3D model generated by recombinant zona pellucida protein-coated beads.

The egg is a spherical cell encapsulated by the zona pellucida (ZP) which forms a filamentous matrix composed of several glycoproteins that mediate gamete recognition at fertilization. Studies on molecular mechanisms of sperm-egg binding are limited in many mammalian species by the scarcity of eggs, by ethical concerns in harvesting eggs, and by the high cost of producing genetically modified animals. To address these limitations, we have reproduced a three-dimensional (3D) model mimicking the oocyte's shape, by means of magnetic sepharose beads coated with recombinant ZP glycoproteins (B) and cumulus cells.