RREB1 regulates neuronal proteostasis and the microtubule network.

Transcription factors play vital roles in neuron development; however, little is known about the role of these proteins in maintaining neuronal homeostasis. Here, we show that the transcription factor RREB1 (Ras-responsive element-binding protein 1) is essential for neuron survival in the mammalian brain. A spontaneous mouse mutation causing loss of a nervous system-enriched transcript is associated with progressive loss of cerebellar Purkinje cells and ataxia.

An allelic series of spontaneous Rorb mutant mice exhibit a gait phenotype, changes in retina morphology and behavior, and gene expression signatures associated with the unfolded protein response.

The Retinoid-related orphan receptor beta (RORβ) gene encodes a developmental transcription factor and has 2 predominant isoforms created through alternative first exon usage; one specific to the retina and another present more broadly in the central nervous system, particularly regions involved in sensory processing. RORβ belongs to the nuclear receptor family and plays important roles in cell fate specification in the retina and cortical layer formation. In mice, loss of RORβ causes disorganized retina layers, postnatal degeneration, and production of immature cone photoreceptors.

Witch Nails (Krt90whnl): A spontaneous mouse mutation affecting nail growth and development.

Numerous single gene mutations identified in humans and mice result in nail deformities with many similarities between the species. A spontaneous, autosomal, recessive mutation called witch nails (whnl) is described here where the distal nail matrix and nail bed undergo degenerative changes resulting in formation of an abnormal nail plate causing mice to develop long, curved nails. This mutation arose spontaneously in a colony of MRL/MpJ-Faslpr/J at The Jackson Laboratory.

Integrated analysis of the molecular pathogenesis of FDXR-associated disease.

The mitochondrial flavoprotein ferredoxin reductase (FDXR) is required for biogenesis of iron-sulfur clusters and for steroidogenesis. Iron-sulfur (Fe-S) clusters are ubiquitous cofactors essential to various cellular processes, and an increasing number of disorders are associated with disruptions in the synthesis of Fe-S clusters. Our previous studies have demonstrated that hypomorphic mutations in FDXR cause a novel mitochondriopathy and optic atrophy in humans and mice, attributed in part to reduced function of the electron transport chain (ETC) as well as elevated production of reactive oxygen species (ROS).

Barriers and facilitators to smoking cessation within pregnant Aboriginal and/or Torres Strait Islander women: An integrative review.

Objective: To synthesise primary research regarding the facilitators and barriers to smoking cessation amongst Aboriginal and/or Torres Strait Islander women during pregnancy.

Design: An integrative review.

Review Methods: A systematic search of peer-reviewed literature from five databases published from January 2008 to April 2018.

Biallelic mutations in FDXR cause neurodegeneration associated with inflammation.

Mitochondrial dysfunction lies behind many neurodegenerative disorders, owing largely to the intense energy requirements of most neurons. Such mitochondrial dysfunction may work through a variety of mechanisms, from direct disruption of the electron transport chain to abnormal mitochondrial biogenesis. Recently, we have identified biallelic mutations in the mitochondrial flavoprotein "ferredoxin reductase" (FDXR) gene as a novel cause of mitochondriopathy, peripheral neuropathy, and optic atrophy.

Biallelic mutations in the ferredoxin reductase gene cause novel mitochondriopathy with optic atrophy.

Iron-sulfur (Fe-S) clusters are ubiquitous cofactors essential to various cellular processes, including mitochondrial respiration, DNA repair, and iron homeostasis. A steadily increasing number of disorders are being associated with disrupted biogenesis of Fe-S clusters. Here, we conducted whole-exome sequencing of patients with optic atrophy and other neurological signs of mitochondriopathy and identified 17 individuals from 13 unrelated families with recessive mutations in FDXR, encoding the mitochondrial membrane-associated flavoprotein ferrodoxin reductase required for electron transport from NADPH to cytochrome P450.

Ectopic Mineralization and Conductive Hearing Loss in Enpp1asj Mutant Mice, a New Model for Otitis Media and Tympanosclerosis.

Otitis media (OM), inflammation of the middle ear, is a common cause of hearing loss in children and in patients with many different syndromic diseases. Studies of the human population and mouse models have revealed that OM is a multifactorial disease with many environmental and genetic contributing factors. Here, we report on otitis media-related hearing loss in asj (ages with stiffened joints) mutant mice, which bear a point mutation in the Enpp1 gene.

Exome sequencing reveals pathogenic mutations in 91 strains of mice with Mendelian disorders.

Spontaneously arising mouse mutations have served as the foundation for understanding gene function for more than 100 years. We have used exome sequencing in an effort to identify the causative mutations for 172 distinct, spontaneously arising mouse models of Mendelian disorders, including a broad range of clinically relevant phenotypes. To analyze the resulting data, we developed an analytics pipeline that is optimized for mouse exome data and a variation database that allows for reproducible, user-defined data mining as well as nomination of mutation candidates through knowledge-based integration of sample and variant data.

Dsp rul: a spontaneous mouse mutation in desmoplakin as a model of Carvajal-Huerta syndrome.

Studies of spontaneous mutations in mice have provided valuable disease models and important insights into the mechanisms of human disease. Ruffled (rul) is a new autosomal recessive mutation causing abnormal hair coat in mice. The rul allele arose spontaneously in the RB156Bnr/EiJ inbred mouse strain.

Contrasting alterations to synaptic and intrinsic properties in upper-cervical superficial dorsal horn neurons following acute neck muscle inflammation.

Background: Acute and chronic pain in axial structures, like the back and neck, are difficult to treat, and have incidence as high as 15%. Surprisingly, most preclinical work on pain mechanisms focuses on cutaneous structures in the limbs and animal models of axial pain are not widely available. Accordingly, we developed a mouse model of acute cervical muscle inflammation and assessed the functional properties of superficial dorsal horn (SDH) neurons.

Hearing impairment in hypothyroid dwarf mice caused by mutations of the thyroid peroxidase gene.

Thyroid hormone (TH) is essential for proper cochlear development and function, and TH deficiencies cause variable hearing impairment in humans and mice. Thyroid peroxidase (TPO) catalyzes key reactions in TH synthesis, and TPO mutations have been found to underlie many cases of congenital hypothyroidism in human patients. In contrast, only a single mutation of the mouse TPO gene has been reported previously (Tpo(R479C)) but was not evaluated for auditory function.

A novel mouse Dscam mutation inhibits localization and shedding of DSCAM.

The differential adhesion hypothesis of development states that patterning of organisms, organs and tissues is mediated in large part by expression of cell adhesion molecules. The cues provided by cell adhesion molecules are also hypothesized to facilitate specific connectivity within the nervous system. In this study we characterize a novel mouse mutation in the gene Dscam (Down Syndrome Cell Adhesion Molecule).

A novel null allele of mouse DSCAM survives to adulthood on an inbred C3H background with reduced phenotypic variability.

DSCAMs are cell adhesion molecules that play several important roles in neurodevelopment. Mouse alleles of Dscam identified to date do not survive on an inbred C57BL/6 background, complicating analysis of DSCAM-dependent developmental processes because of phenotypic variability related to the segregating backgrounds needed for postnatal survival. A novel spontaneous allele of Dscam, hereafter referred to as Dscam²(J), has been identified.

The mouse mutation "thrombocytopenia and cardiomyopathy" (trac) disrupts Abcg5: a spontaneous single gene model for human hereditary phytosterolemia/sitosterolemia.

The spontaneous mouse mutation "thrombocytopenia and cardiomyopathy" (trac) causes macrothrombocytopenia, prolonged bleeding times, anemia, leukopenia, infertility, cardiomyopathy, and shortened life span. Homozygotes show a 20-fold decrease in platelet numbers and a 3-fold increase in platelet size with structural alterations and functional impairments in activation and aggregation. Megakaryocytes in trac/trac mice are present in increased numbers, have poorly developed demarcation membrane systems, and have decreased polyploidy.

The podosomal-adaptor protein SH3PXD2B is essential for normal postnatal development.

Podosome-type adhesions are actin-based membrane protrusions involved in cell-matrix adhesion and extracellular matrix degradation. Despite growing knowledge of many proteins associated with podosome-type adhesions, much remains unknown concerning the function of podosomal proteins at the level of the whole animal. In this study, the spontaneous mouse mutant nee was used to identify a component of podosome-type adhesions that is essential for normal postnatal growth and development.

Mouse H6 Homeobox 1 (Hmx1) mutations cause cranial abnormalities and reduced body mass.

Background: The H6 homeobox genes Hmx1, Hmx2, and Hmx3 (also known as Nkx5-3; Nkx5-2 and Nkx5-1, respectively), compose a family within the NKL subclass of the ANTP class of homeobox genes. Hmx gene family expression is mostly limited to sensory organs, branchial (pharyngeal) arches, and the rostral part of the central nervous system. Targeted mutation of either Hmx2 or Hmx3 in mice disrupts the vestibular system.

Notch signalling in the paraxial mesoderm is most sensitive to reduced Pofut1 levels during early mouse development.

Background: The evolutionarily conserved Notch signalling pathway regulates multiple developmental processes in a wide variety of organisms. One critical posttranslational modification of Notch for its function in vivo is the addition of O-linked fucose residues by protein O-fucosyltransferase 1 (POFUT1). In addition, POFUT1 acts as a chaperone and is required for Notch trafficking.

Protein accumulation and neurodegeneration in the woozy mutant mouse is caused by disruption of SIL1, a cochaperone of BiP.

Endoplasmic reticulum (ER) chaperones and ER stress have been implicated in the pathogenesis of neurodegenerative disorders, such as Alzheimer and Parkinson diseases, but their contribution to neuron death remains uncertain. In this study, we establish a direct in vivo link between ER dysfunction and neurodegeneration. Mice homozygous with respect to the woozy (wz) mutation develop adult-onset ataxia with cerebellar Purkinje cell loss.

Fine Mapping of a Deafness Mutation hml on Mouse Chromosome 10.

OBJECTIVE: to map a mouse deafness gene, identify the underlying mutation and develop a mouse model for human deafness. METHODS: genetic linkage cross and genome scan were used to map a novel mutation named hypoplasia of the membranous labyrinth (hml), which causes hearing loss in mutant mice. RESULTS: 1.

Curly bare (cub), a new mouse mutation on chromosome 11 causing skin and hair abnormalities, and a modifier gene (mcub) on chromosome 5.

In the outcrossing of a new recessive mouse mutation causing hair loss, a new wavy-coated phenotype appeared. The two distinct phenotypes were shown to be alternative manifestations of the same gene mutation and attributable to a single modifier locus. The new mutation, curly bare (cub), was mapped to distal Chr 11 and the modifier (mcub) was mapped to Chr 5.

The netrin 1 receptors Unc5h3 and Dcc are necessary at multiple choice points for the guidance of corticospinal tract axons.

Migrating axons require the correct presentation of guidance molecules, often at multiple choice points, to find their target. Netrin 1, a bifunctional cue involved in both attracting and repelling axons, is involved in many cell migration and axon pathfinding processes in the CNS. The netrin 1 receptor DCC and its Caenorhabditis elegans homolog UNC-40 have been implicated in directing the guidance of axons toward netrin sources, whereas the C.

Purkinje cell degeneration (pcd) phenotypes caused by mutations in the axotomy-induced gene, Nna1.

The classical recessive mouse mutant, Purkinje cell degeneration (pcd), exhibits adult-onset degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory bulb mitral neurons, and selected thalamic neurons, and has defective spermatogenesis. Here we identify Nna1 as the gene mutated in the original pcd and two additional pcd alleles (pcd2J and pcd3J). Nna1 encodes a putative nuclear protein containing a zinc carboxypeptidase domain initially identified by its induction in spinal motor neurons during axonal regeneration.