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Eunju Seong, Ryan Insolera, Marija Dulovic, Erik-Jan Kamsteeg, Joanne Trinh, Norbert Brüggemann, Erin Sandford, Sheng Li, Ayse Bilge Ozel, Jun Z Li, Tamison Jewett, Anneke J A Kievit, Alexander Münchau, Vikram Shakkottai, Christine Klein, Catherine Collins, Katja Lohmann, Bart P van de Warrenburg, Margit Burmeister
OBJECTIVE: To identify novel causes of recessive ataxias, including spinocerebellar ataxia with saccadic intrusions, spastic ataxias and spastic paraplegia. METHODS: In an international collaboration, we independently performed exome sequencing in seven families with recessive ataxia and/or spastic paraplegia. To evaluate the role of VPS13D mutations, we evaluated a Drosophila knock-out model and investigated mitochondrial function in patient-derived fibroblast cultures...
March 31, 2018: Annals of Neurology
Julie Gauthier, Inge A Meijer, Davor Lessel, Niccolò E Mencacci, Dimitri Krainc, Maja Hempel, Konstantinos Tsiakas, Holger Prokisch, Elsa Rossignol, Margaret H Helm, Lance H Rodan, Jason Karamchandani, Miryam Carecchio, Steven J Lubbe, Aida Telegrafi, Lindsay B Henderson, Kerry Lorenzo, Stephanie E Wallace, Ian A Glass, Fadi F Hamdan, Jacques L Michaud, Guy A Rouleau, Philippe M Campeau
VPS13 protein family members VPS13A through VPS13C have been associated with various recessive movement disorders. We describe the first disease association of rare recessive VPS13D variants including frameshift, missense, and partial duplication mutations with a novel complex, hyperkinetic neurological disorder. The clinical features include developmental delay, a childhood onset movement disorder (chorea, dystonia, or tremor), and progressive spastic ataxia or paraparesis. Characteristic brain magnetic resonance imaging shows basal ganglia or diffuse white matter T2 hyperintensities as seen in Leigh syndrome and choreoacanthocytosis...
March 8, 2018: Annals of Neurology
Tsuyoshi S Nakamura, Yumi Numajiri, Yuuya Okumura, Junji Hidaka, Takayuki Tanaka, Ichiro Inoue, Yasuyuki Suda, Tetsuo Takahashi, Hideki Nakanishi, Xiao-Dong Gao, Aaron M Neiman, Hiroyuki Tachikawa
During the developmental process of sporulation in Saccharomyces cerevisiae, membrane structures called prospore membranes are formed de novo, expand, extend, round up, and finally become plasma membranes of the spores. GIP1 encodes a regulatory/targeting subunit of protein phosphatase type 1 that is required for sporulation. Gip1 recruits the catalytic subunit Glc7 to septin structures that form along the prospore membrane; however, the molecular basis of its localization and function is not fully understood...
October 18, 2017: Molecular Biology of the Cell
Arun T John Peter, Beatrice Herrmann, Diana Antunes, Doron Rapaport, Kai Stefan Dimmer, Benoît Kornmann
Membrane contact sites between endoplasmic reticulum (ER) and mitochondria, mediated by the ER-mitochondria encounter structure (ERMES) complex, are critical for mitochondrial homeostasis and cell growth. Defects in ERMES can, however, be bypassed by point mutations in the endosomal protein Vps13 or by overexpression of the mitochondrial protein Mcp1. How this bypass operates remains unclear. Here we show that the mitochondrial outer membrane protein Mcp1 functions in the same pathway as Vps13 by recruiting it to mitochondria and promoting its association to vacuole-mitochondria contacts...
October 2, 2017: Journal of Cell Biology
Weronika Rzepnikowska, Krzysztof Flis, Sandra Muñoz-Braceras, Regina Menezes, Ricardo Escalante, Teresa Zoladek
Human Vps13 proteins are associated with several diseases, including the neurodegenerative disorder Chorea-acanthocytosis (ChAc), yet the biology of these proteins is still poorly understood. Studies in Saccharomyces cerevisiae, Dictyostelium discoideum, Tetrahymena thermophila and Drosophila melanogaster point to the involvement of Vps13 in cytoskeleton organization, vesicular trafficking, autophagy, phagocytosis, endocytosis, proteostasis, sporulation and mitochondrial functioning. Recent findings show that yeast Vps13 binds to phosphatidylinositol lipids via 4 different regions and functions at membrane contact sites, enlarging the list of Vps13 functions...
August 28, 2017: Traffic
Yong Xue, Stefan Schmollinger, Narsis Attar, Oscar A Campos, Maria Vogelauer, Michael F Carey, Sabeeha S Merchant, Siavash K Kurdistani
The endoplasmic reticulum (ER)-mitochondria encounter structure (ERMES) is a protein complex that physically tethers the two organelles to each other and creates the physical basis for communication between them. ERMES functions in lipid exchange between the ER and mitochondria, protein import into mitochondria, and maintenance of mitochondrial morphology and genome. Here, we report that ERMES is also required for iron homeostasis. Loss of ERMES components activates an Aft1-dependent iron deficiency response even in iron-replete conditions, leading to accumulation of excess iron inside the cell...
August 11, 2017: Journal of Biological Chemistry
Anuradha Chowdhary, Ferry Hagen, Cheshta Sharma, Abdullah M S Al-Hatmi, Letterio Giuffrè, Domenico Giosa, Shangrong Fan, Hamid Badali, Maria Rosa Felice, Sybren de Hoog, Jacques F Meis, Orazio Romeo
This study aimed at investigating the genetic diversity of a panel of Candida africana strains recovered from vaginal samples in different countries. All fungal strains were heterozygous at the mating-type-like locus and belonged to the genotype A of Candida albicans . Moreover, all examined C. africana strains lack N -acetylglucosamine assimilation and sequence analysis of the HXK1 gene showed a distinctive polymorphism that impair the utilization of this amino sugar in this yeast. Multi-locus sequencing of seven housekeeping genes revealed a substantial genetic homogeneity among the strains, except for the CaMPIb, SYA1 and VPS13 loci which contributed significantly to the classification of our set of C...
2017: Frontiers in Microbiology
Lauren E Dalton, Björn D M Bean, Michael Davey, Elizabeth Conibear
P4-ATPases are a family of putative phospholipid flippases that regulate lipid membrane asymmetry, which is important for vesicle formation. Two yeast flippases, Drs2 and Neo1, have nonredundant functions in the recycling of the synaptobrevin-like v-SNARE Snc1 from early endosomes. Drs2 activity is needed to form vesicles and regulate its own trafficking, suggesting that flippase activity and localization are linked. However, the role of Neo1 in endosomal recycling is not well characterized. To identify novel regulators of Neo1 trafficking and activity at endosomes, we first identified mutants with impaired recycling of a Snc1-based reporter and subsequently used high-content microscopy to classify these mutants based on the localization of Neo1 or its binding partners, Mon2 and Dop1...
June 1, 2017: Molecular Biology of the Cell
Weronika Rzepnikowska, Krzysztof Flis, Joanna Kaminska, Marcin Grynberg, Agnieszka Urbanek, Kathryn R Ayscough, Teresa Zoladek
The rare human disorder chorea-acanthocytosis (ChAc) is caused by mutations in hVPS13A gene. The hVps13A protein interacts with actin and regulates the level of phosphatidylinositol 4-phosphate (PI4P) in the membranes of neuronal cells. Yeast Vps13 is involved in vacuolar protein transport and, like hVps13A, participates in PI4P metabolism. Vps13 proteins are conserved in eukaryotes, but their molecular function remains unknown. One of the mutations found in ChAc patients causes amino acids substitution I2771R which affects the localization of hVps13A in skeletal muscles...
April 15, 2017: Human Molecular Genetics
Margaret D Myers, Gregory S Payne
Yeast Vps13 is a member of a conserved protein family that includes human homologues associated with neurodegenerative and developmental disorders. In this issue, De et al. (2017. J. Cell Biol. establish direct roles for Vps13 and its surprising binding partner, the calcium-binding centrin Cdc31, in trans-Golgi network (TGN) to endosome traffic and TGN homotypic fusion.
February 2017: Journal of Cell Biology
Mithu De, Austin N Oleskie, Mariam Ayyash, Somnath Dutta, Liliya Mancour, Mohamed E Abazeed, Eddy J Brace, Georgios Skiniotis, Robert S Fuller
Yeast VPS13 is the founding member of a eukaryotic gene family of growing interest in cell biology and medicine. Mutations in three of four human VPS13 genes cause autosomal recessive neurodegenerative or neurodevelopmental disease, making yeast Vps13p an important structural and functional model. Using cell-free reconstitution with purified Vps13p, we show that Vps13p is directly required both for transport from the trans-Golgi network (TGN) to the late endosome/prevacuolar compartment (PVC) and for TGN homotypic fusion...
February 2017: Journal of Cell Biology
Jan J Vonk, Wondwossen M Yeshaw, Francesco Pinto, Anita I E Faber, Liza L Lahaye, Bart Kanon, Marianne van der Zwaag, Antonio Velayos-Baeza, Raimundo Freire, Sven C van IJzendoorn, Nicola A Grzeschik, Ody C M Sibon
Chorea-Acanthocytosis is a rare, neurodegenerative disorder characterized by progressive loss of locomotor and cognitive function. It is caused by loss of function mutations in the Vacuolar Protein Sorting 13A (VPS13A) gene, which is conserved from yeast to human. The consequences of VPS13A dysfunction in the nervous system are still largely unspecified. In order to study the consequences of VPS13A protein dysfunction in the ageing central nervous system we characterized a Drosophila melanogaster Vps13 mutant line...
2017: PloS One
Yuuya Okumura, Tsuyoshi S Nakamura, Takayuki Tanaka, Ichiro Inoue, Yasuyuki Suda, Tetsuo Takahashi, Hideki Nakanishi, Shugo Nakamura, Xiao-Dong Gao, Hiroyuki Tachikawa
Sporulation of Saccharomyces cerevisiae is a developmental process in which an ascus containing four haploid spores forms from a diploid cell. During this process, newly formed membrane structures called prospore membranes extend along the nuclear envelope and engulf and package daughter nuclei along with cytosol and organelles to form precursors of spores. Proteins involved in prospore membrane extension, Vps13 and Spo71, have recently been reported; however, the overall mechanism of membrane extension remains unclear...
January 2016: MSphere
Jae-Sook Park, Mary K Thorsness, Robert Policastro, Luke L McGoldrick, Nancy M Hollingsworth, Peter E Thorsness, Aaron M Neiman
The Vps13 protein family is highly conserved in eukaryotic cells. Mutations in human VPS13 genes result in a variety of diseases, such as chorea acanthocytosis (ChAc), but the cellular functions of Vps13 proteins are not well defined. In yeast, there is a single VPS13 orthologue, which is required for at least two different processes: protein sorting to the vacuole and sporulation. This study demonstrates that VPS13 is also important for mitochondrial integrity. In addition to preventing transfer of DNA from the mitochondrion to the nucleus, VPS13 suppresses mitophagy and functions in parallel with the endoplasmic reticulum-mitochondrion encounter structure (ERMES)...
August 1, 2016: Molecular Biology of the Cell
Ri-Yao Yang, Huiting Xue, Lan Yu, Antonio Velayos-Baeza, Anthony P Monaco, Fu-Tong Liu
Galectin-12, a member of the galectin family of β-galactoside-binding animal lectins, is preferentially expressed in adipocytes and required for adipocyte differentiation in vitro. This protein was recently found to regulate lipolysis, whole body adiposity, and glucose homeostasis in vivo. Here we identify VPS13C, a member of the VPS13 family of vacuolar protein sorting-associated proteins highly conserved throughout eukaryotic evolution, as a major galectin-12-binding protein. VPS13C is upregulated during adipocyte differentiation, and is required for galectin-12 protein stability...
2016: PloS One
Emily M Parodi, Joseph M Roesner, Linda S Huang
In the yeast Saccharomyces cerevisiae, cells undergoing sporulation form prospore membranes to surround their meiotic nuclei. The prospore membranes ultimately become the plasma membranes of the new cells. The putative phospholipase Spo1 and the tandem Pleckstrin Homology domain protein Spo71 have previously been shown to be required for prospore membrane development, along with the constitutively expressed Vps13 involved in vacuolar sorting. Here, we utilize genetic analysis, and find that SPO73 is required for proper prospore membrane shape and, like SPO71, is necessary for prospore membrane elongation...
2015: PloS One
Alexander B Lang, Arun T John Peter, Peter Walter, Benoît Kornmann
The endoplasmic reticulum-mitochondria encounter structure (ERMES) complex tethers the endoplasmic reticulum and the mitochondria. It is thought to facilitate interorganelle lipid exchange and influence mitochondrial dynamics and mitochondrial DNA maintenance. Despite this important role, ERMES is not found in metazoans. Here, we identified single amino acid substitutions in Vps13 (vacuolar protein sorting 13), a large universally conserved eukaryotic protein, which suppress all measured phenotypic consequences of ERMES deficiency...
September 14, 2015: Journal of Cell Biology
Sandra Muñoz-Braceras, Rosa Calvo, Ricardo Escalante
Deficient autophagy causes a distinct phenotype in Dictyostelium discoideum, characterized by the formation of multitips at the mound stage. This led us to analyze autophagy in a number of multitipped mutants described previously (tipA(-), tipB(-), tipC(-), and tipD(-)). We found a clear autophagic dysfunction in tipC(-) and tipD(-) while the others showed no defects. tipD codes for a homolog of Atg16, which confirms the role of this protein in Dictyostelium autophagy and validates our approach. The tipC-encoded protein is highly similar to human VPS13A (also known as chorein), whose mutations cause the chorea-acanthocytosis syndrome...
2015: Autophagy
Jae-Sook Park, Simon Halegoua, Shosei Kishida, Aaron M Neiman
The Vps13 protein family is highly conserved in eukaryotic cells. In humans, mutations in the gene encoding the family member VPS13A lead to the neurodegenerative disorder chorea-acanthocytosis. In the yeast Saccharomyces cerevisiae, there is just a single version of VPS13, thereby simplifying the task of unraveling its molecular function(s). While VPS13 was originally identified in yeast by its role in vacuolar sorting, recent studies have revealed a completely different function for VPS13 in sporulation, where VPS13 regulates phosphatidylinositol-4-phosphate (PtdIns(4)P) levels in the prospore membrane...
2015: PloS One
Zhaofei Li, Gary Blissard
In eukaryotic cells, regulated vesicular trafficking is critical for directing protein transport and for recycling and degradation of membrane lipids and proteins. Through carefully regulated transport vesicles, the endomembrane system performs a large and important array of dynamic cellular functions while maintaining the integrity of the cellular membrane system. Genetic studies in yeast Saccharomyces cerevisiae have identified approximately 50 vacuolar protein sorting (VPS) genes involved in vesicle trafficking, and most of these genes are also characterized in mammals...
July 2015: Insect Biochemistry and Molecular Biology
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