https://nova.newcastle.edu.au/vital/access/manager/Index ${session.getAttribute("locale")} 5 Repetitive sperm-induced Ca²⁺ transients in mouse oocytes are cell cycle dependent https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6546 Wed 11 Apr 2018 16:15:33 AEST ]]> Mouse Emi2 is required to enter meiosis II by reestablishing cyclin B1 during interkinesis https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6545 Wed 11 Apr 2018 14:52:54 AEST ]]> Kif4 is essential for mouse oocyte meiosis https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30985 Wed 11 Apr 2018 14:34:15 AEST ]]> Characterisation of an oocyte specific knockout model of Cdh1 https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11553 Wed 11 Apr 2018 14:19:59 AEST ]]> A novel mechanism controls the Ca²⁺ oscillations triggered by activation of ascidian eggs and has an absolute requirement for Cdk1 activity https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6552 Wed 11 Apr 2018 13:43:05 AEST ]]> DNA repair and the Fanconi Anemia pathway: insights into female meiosis and mitosis https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:13344 Wed 11 Apr 2018 12:45:22 AEST ]]> Premature dyad separation in meiosis II is the major segregation error with maternal age in mouse oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:21342 Wed 11 Apr 2018 12:17:52 AEST ]]> The APC activator fizzy-related-1 (FZR1) is needed for preimplantation mouse embryo development https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:21729 Fzr1 knockout mouse embryos show normal preimplantation development but die due to a lack of endoreduplication needed for placentation. However, interpretation of the role of FZR1 during this period is hindered by the presence of maternal stores. In this study, therefore, we used an oocyte-specific knockout to examine FZR1 function in early mouse embryo development. Maternal FZR1 was not crucial for completion of meiosis, and furthermore viable pups were born to Fzr1 knockout females mated with normal males. However, in early embryos the absence of both maternal and paternal FZR1 led to a dramatic loss in genome integrity, such that the majority of embryos arrested having undergone only a single mitotic division and contained many γ-H2AX foci, consistent with fragmented DNA. A prominent feature of such embryos was the establishment of two independent spindles following pronuclear fusion and thus a failure of the chromosomes to mix (syngamy). These generated binucleate 2-cell embryos. In the 10% of embryos that progressed to the 4-cell stage, division was so slow that compaction occurred prematurely. No embryo development to the blastocyst stage was ever observed. We conclude that Fzr1 is a surprisingly essential gene involved in the establishment of a single spindle from the two pronuclei in 1-cell embryos as well as being involved in the maintenance of genomic integrity during the mitotic divisions of early mammalian embryos.]]> Wed 11 Apr 2018 11:35:19 AEST ]]> How eggs arrest at metaphase II: MPF stabilisation plus APC/C inhibition equals Cytostatic Factor https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6549 Wed 11 Apr 2018 10:43:58 AEST ]]> Start and stop signals of oocyte meiotic maturation https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:18182 Tue 23 Jun 2015 18:36:00 AEST ]]> The small non-coding RNA profile of mouse oocytes is modified during aging https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:35834 Kifc1 and Kifc5b, in aged oocytes; family members selectively targeted for expression regulation by endo-siRNAs of elevated abundance. The implications of reduced Kifc1 and Kifc5b expression were explored using complementary siRNA-mediated knockdown and pharmacological inhibition strategies, both of which led to increased rates of aneuploidy in otherwise healthy young oocytes. Collectively, our data raise the prospect that altered sRNA abundance, specifically endo-siRNA abundance, could influence the quality of the aged oocyte.]]> Tue 10 Dec 2019 16:34:23 AEDT ]]> Time-lapse epifluorescence imaging of expressed cRNA to cyclin B1 for studying meiosis i in mouse oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:24275 Thu 17 Nov 2016 17:26:48 AEDT ]]> Motoring through: the role of kinesin superfamily proteins in female meiosis https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30367 Thu 03 Feb 2022 12:18:59 AEDT ]]> miRNA and mammalian male germ cells https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:21531 Sat 24 Mar 2018 10:24:55 AEDT ]]> Mouse germ cell development: from specification to sex determination https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:9702 Sat 24 Mar 2018 08:34:38 AEDT ]]> Spatial regulation of APC<sup>Cdh1</sup>-induced cyclin B1 degradation maintains G2 arrest in mouse oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11246 Cdh1) activity, which ubiquitylates and so targets cyclin B1 for degradation. Thus, APCCdh1 activity prevents precocious meiotic entry by promoting cyclin B1 degradation. However, it remains unresolved how cyclin B1 levels are suppressed sufficiently to maintain arrest but not so low that they make oocytes hormonally insensitive. Here, we examined spatial control of this process by determining the intracellular location of the proteins involved and using nuclear-targeted cyclin B1. We found that raising nuclear cyclin B1 concentrations, an event normally observed in the minutes before nuclear envelope breakdown, was a very effective method of inducing the G2/M transition. Oocytes expressed only the α-isoform of Cdh1, which was predominantly nuclear, as were Cdc27 and Psmd11, core components of the APC and the 26S proteasome, respectively. Furthermore, APCCdh1 activity appeared higher in the nucleus, as nuclear-targeted cyclin B1 was degraded at twice the rate of wild-type cyclin B1. We propose a simple spatial model of G2 arrest in which nuclear APCCdh1-proteasomal activity guards against any cyclin B1 accumulation mediated by nuclear import.]]> Sat 24 Mar 2018 08:10:55 AEDT ]]> A male-specific role for p38 mitogen-activated protein kinase in germ cell sex differentiation in mice https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:11166 Sat 24 Mar 2018 08:08:30 AEDT ]]> Chromosomal, metabolic, environmental, and hormonal origins of aneuploidy in mammalian oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:17343 Sat 24 Mar 2018 08:01:41 AEDT ]]> The APC/C activator FZR1 is essential for meiotic prophase I in mice https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:21158 FZR1 activity in the male germline led to both a mitotic and a meiotic testicular defect resulting in infertility due to the absence of mature spermatozoa. Spermatogonia in the prepubertal testes of such mice had abnormal proliferation and delayed entry into meiosis. Although early recombination events were initiated, male germ cells failed to progress beyond zygotene and underwent apoptosis. Loss of APC/CFZR1 activity was associated with raised cyclin B1 levels, suggesting that CDK1 may trigger apoptosis. By contrast, female FZR1Δ mice were subfertile, with premature onset of ovarian failure by 5 months of age. Germ cell loss occurred embryonically in the ovary, around the time of the zygotene-pachytene transition, similar to that observed in males. In addition, the transition of primordial follicles into the growing follicle pool in the neonatal ovary was abnormal, such that the primordial follicles were prematurely depleted. We conclude that APC/CFZR1 is an essential regulator of spermatogonial proliferation and early meiotic prophase I in both male and female germ cells and is therefore important in establishing the reproductive health of adult male and female mammals.]]> Sat 24 Mar 2018 08:00:18 AEDT ]]> Increased zona pellucida thickness and meiotic spindle disruption in oocytes from cigarette smoking mice https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:17909 Sat 24 Mar 2018 07:56:41 AEDT ]]> Developmental expression of Musashi-1 and Musashi-2 RNA-binding proteins during spermatogenesis: analysis of the deleterious effects of dysregulated expression https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:20640 Sat 24 Mar 2018 07:55:44 AEDT ]]> Reduced ability to recover from spindle disruption and loss of kinetochore spindle assembly checkpoint proteins in oocytes from aged mice https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:20695 Sat 24 Mar 2018 07:55:41 AEDT ]]> Reduced chromosome cohesion measured by interkinetochore distance is associated with aneuploidy even in oocytes from young mice https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:20166 Sat 24 Mar 2018 07:51:44 AEDT ]]> Securin and not CDK1/cyclin B1 regulates sister chromatid disjunction during meiosis II in mouse eggs https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:5601 Sat 24 Mar 2018 07:49:25 AEDT ]]> SIAH1 targets the alternative splicing factor T-STAR for degradation by the proteasome https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6573 Sat 24 Mar 2018 07:49:17 AEDT ]]> Maintenance of sister chromatid attachment in mouse eggs through maturation-promoting factor activity https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6574 Sat 24 Mar 2018 07:49:16 AEDT ]]> Ca²⁺ oscillations promote APC/C-dependent cyclin B1 degradation during metaphase arrest and completion of meiosis in fertilizing mouse eggs https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6570 Sat 24 Mar 2018 07:49:16 AEDT ]]> Meiotic and mitotic Ca²⁺ oscillations affect cell composition in resulting blastocysts https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6585 Sat 24 Mar 2018 07:49:10 AEDT ]]> The CRY box: a second APCcdh¹-dependent degron in mammalian cdc20 https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6556 Sat 24 Mar 2018 07:48:22 AEDT ]]> Control of homologous chromosome division in the mammalian oocyte https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6539 Sat 24 Mar 2018 07:48:19 AEDT ]]> Meiosis in oocytes: predisposition to aneuploidy and its increased incidence with age https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6538 Sat 24 Mar 2018 07:48:18 AEDT ]]> Essential CDK1-inhibitory role for separase during meiosis I in vertebrate oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:6562 Sat 24 Mar 2018 07:47:07 AEDT ]]> Differential regulation of cyclin B1 degradation between the first and second meiotic divisions of bovine oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:25109 Sat 24 Mar 2018 07:17:14 AEDT ]]> Non-coding RNA in spermatogenesis and epididymal maturation https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:24273 Sat 24 Mar 2018 07:14:56 AEDT ]]> Anaphase-promoting complex control in female mouse meiosis https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:23214 Sat 24 Mar 2018 07:10:28 AEDT ]]> The control of meiotic maturation in mammalian oocytes https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:20165 Mon 24 Aug 2015 15:22:23 AEST ]]>