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1.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612777

RESUMO

High-grade gliomas (HGGs) and glioblastoma multiforme (GBM) are characterized by a heterogeneous and aggressive population of tissue-infiltrating cells that promote both destructive tissue remodeling and aberrant vascularization of the brain. The formation of defective and permeable blood vessels and microchannels and destructive tissue remodeling prevent efficient vascular delivery of pharmacological agents to tumor cells and are the significant reason why therapeutic chemotherapy and immunotherapy intervention are primarily ineffective. Vessel-forming endothelial cells and microchannel-forming glial cells that recapitulate vascular mimicry have both infiltration and destructive remodeling tissue capacities. The transmembrane protein TMEM230 (C20orf30) is a master regulator of infiltration, sprouting of endothelial cells, and microchannel formation of glial and phagocytic cells. A high level of TMEM230 expression was identified in patients with HGG, GBM, and U87-MG cells. In this study, we identified candidate genes and molecular pathways that support that aberrantly elevated levels of TMEM230 play an important role in regulating genes associated with the initial stages of cell infiltration and blood vessel and microchannel (also referred to as tumor microtubule) formation in the progression from low-grade to high-grade gliomas. As TMEM230 regulates infiltration, vascularization, and tissue destruction capacities of diverse cell types in the brain, TMEM230 is a promising cancer target for heterogeneous HGG tumors.


Assuntos
Glioblastoma , Glioma , Doença de Parkinson , Humanos , Glioblastoma/genética , Proteínas de Membrana/genética , Células Endoteliais , Angiogênese , Glioma/genética , Neuroglia , Neovascularização Patológica/genética
2.
J Cell Physiol ; 233(2): 1455-1467, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28542953

RESUMO

During embryonic development, new arteries, and veins form from preexisting vessels in response to specific angiogenic signals. Angiogenic signaling is complex since not all endothelial cells exposed to angiogenic signals respond equally. Some cells will be selected to become tip cells and acquire migration and proliferation capacity necessary for vessel growth while others, the stalk cells become trailer cells that stay connected with pre-existing vessels and act as a linkage to new forming vessels. Additionally, stalk and tip cells have the capacity to interchange their roles. Stalk and tip cellular responses are mediated in part by the interactions of components of the Delta/Notch and Vegf signaling pathways. We have identified in zebrafish, that the transmembrane protein Tmem230a is a novel regulator of angiogenesis by its capacity to regulate the number of the endothelial cells in intersegmental vessels by co-operating with the Delta/Notch signaling pathway. Modulation of Tmem230a expression by itself is sufficient to rescue improper number of endothelial cells induced by aberrant expression or inhibition of the activity of genes associated with the Dll4/Notch pathway in zebrafish. Therefore, Tmem230a may have a modulatory role in vessel-network formation and growth. As the Tmem230 sequence is conserved in human, Tmem230 may represent a promising novel target for drug discovery and for disease therapy and regenerative medicine in promoting or restricting angiogenesis.


Assuntos
Proliferação de Células , Células Endoteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Neovascularização Fisiológica , Receptores Notch/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Sequência de Bases , Sequência Conservada , Regulação da Expressão Gênica no Desenvolvimento , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Receptores Notch/genética , Transdução de Sinais , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
3.
J Cell Physiol ; 232(6): 1262-1269, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27631155

RESUMO

Cellular reprogramming by epigenomic remodeling of chromatin holds great promise in the field of human regenerative medicine. As an example, human-induced Pluripotent Stem Cells (iPSCs) obtained by reprograming of patient somatic cells are sufficiently similar to embryonic stem cells (ESCs) and can generate all cell types of the human body. Clinical use of iPSCs is dependent on methods that do not utilize genome altering transgenic technologies that are potentially unsafe and ethically unacceptable. Transient delivery of exogenous RNA into cells provides a safer reprogramming system to transgenic approaches that rely on exogenous DNA or viral vectors. RNA reprogramming may prove to be more suitable for clinical applications and provide stable starting cell lines for gene-editing, isolation, and characterization of patient iPSC lines. The introduction and rapid evolution of CRISPR/Cas9 gene-editing systems has provided a readily accessible research tool to perform functional human genetic experiments. Similar to RNA reprogramming, transient delivery of mRNA encoding Cas9 in combination with guide RNA sequences to target specific points in the genome eliminates the risk of potential integration of Cas9 plasmid constructs. We present optimized RNA-based laboratory procedure for making and editing iPSCs. In the near-term these two powerful technologies are being harnessed to dissect mechanisms of human development and disease in vitro, supporting both basic, and translational research. J. Cell. Physiol. 232: 1262-1269, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Doença , Edição de Genes , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Biológicos , RNA/metabolismo , Diferenciação Celular , Reprogramação Celular , Descoberta de Drogas , Vetores Genéticos/metabolismo , Humanos , Medicina de Precisão
4.
J Cell Biochem ; 118(3): 570-584, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27632571

RESUMO

Recent studies suggest that human tumors are generated from cancer cells with stem cell (SC) properties. Spontaneously occurring cancers in dogs contain a diversity of cells that like for human tumors suggest that certain canine tumors are also generated from cancer stem cells (CSCs). CSCs, like normal SCs, have the capacity for self-renewal as mammospheres in suspension cultures. To understand how cells with SC properties contribute to canine mammary gland tumor development and progression, comparative analysis between normal SCs and CSCs, obtained from the same individual, is essential. We have utilized the property of sphere formation to develop culture conditions for propagating stem/progenitor cells from canine normal and tumor tissue. We show that cells from dissociated mammospheres retain sphere reformation capacity for several serial passages and have the capacity to generate organoid structures ex situ. Utilizing various culture conditions for passaging SCs and CSCs, fibroblast growth factor 2 (FGF2) and epidermal growth factor (EGF) were found to positively or negatively regulate mammosphere regeneration, organoid formation, and multi-lineage differentiation potential. The response of FGF2 and EGF on SCs and CSCs was different, with increased FGF2 and EGF self-renewal promoted in SCs and repressed in CSCs. Our protocol for propagating SCs from normal and tumor canine breast tissue will provide new opportunities in comparative mammary gland stem cell analysis between species and anticancer treatment and therapies for dogs. J. Cell. Biochem. 118: 570-584, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Proliferação de Células/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Neoplasias Mamárias Animais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Organoides/metabolismo , Animais , Cães , Feminino , Neoplasias Mamárias Animais/patologia , Células-Tronco Neoplásicas/patologia , Organoides/patologia , Células Tumorais Cultivadas
5.
Adv Protein Chem Struct Biol ; 141: 255-297, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38960477

RESUMO

Glial cells provide physical and chemical support and protection for neurons and for the extracellular compartments of neural tissue through secretion of soluble factors, insoluble scaffolds, and vesicles. Additionally, glial cells have regenerative capacity by remodeling their physical microenvironment and changing physiological properties of diverse cell types in their proximity. Various types of aberrant glial and macrophage cells are associated with human diseases, disorders, and malignancy. We previously demonstrated that transmembrane protein, TMEM230 has tissue revascularization and regenerating capacity by its ability to secrete pro-angiogenic factors and metalloproteinases, inducing endothelial cell sprouting and channel formation. In healthy normal neural tissue, TMEM230 is predominantly expressed in glial and marcophate cells, suggesting a prominent role in neural tissue homeostasis. TMEM230 regulation of the endomembrane system was supported by co-expression with RNASET2 (lysosome, mitochondria, and vesicles) and STEAP family members (Golgi complex). Intracellular trafficking and extracellular secretion of glial cellular components are associated with endocytosis, exocytosis and phagocytosis mediated by motor proteins. Trafficked components include metalloproteins, metalloproteinases, glycans, and glycoconjugate processing and digesting enzymes that function in phagosomes and vesicles to regulate normal neural tissue microenvironment, homeostasis, stress response, and repair following neural tissue injury or degeneration. Aberrantly high sustained levels TMEM230 promotes metalloprotein expression, trafficking and secretion which contribute to tumor associated infiltration and hypervascularization of high tumor grade gliomas. Following injury of the central nervous or peripheral systems, transcient regulated upregulation of TMEM230 promotes tissue wound healing, remodeling and revascularization by activating glial and macrophage generated microchannels/microtubules (referred to as vascular mimicry) and blood vessel sprouting and branching. Our results support that TMEM230 may act as a master regulator of motor protein mediated trafficking and compartmentalization of a large class of metalloproteins in gliomas and gliosis.


Assuntos
Glioma , Gliose , Proteínas de Membrana , Humanos , Proteínas de Membrana/metabolismo , Glioma/metabolismo , Glioma/patologia , Gliose/metabolismo , Gliose/patologia , Animais , Receptores de Peptídeos
6.
Adv Protein Chem Struct Biol ; 141: 299-329, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38960478

RESUMO

TMEM230 promotes antigen processing, trafficking, and presentation by regulating the endomembrane system of membrane bound organelles (lysosomes, proteosomes and mitochondria) and phagosomes. Activation of the immune system requires trafficking of various cargos between the endomembrane system and cell plasma membrane. The Golgi apparatus is the hub of the endomembrane system and essential for the generation, maintenance, recycling, and trafficking of the components of the endomembrane system itself and immune system. Intracellular trafficking and secretion of immune system components depend on mitochondrial metalloproteins for ATP synthesis that powers motor protein transport of endomembrane cargo. Glycan modifying enzyme genes and motor proteins are essential for the activation of the immune system and trafficking of antigens between the endomembrane system and the plasma membrane. Recently, TMEM230 was identified as co-regulated with RNASET2 in lysosomes and with metalloproteins in various cell types and organelles, including mitochondria in autoimmune diseases. Aberrant metalloproteinase secretion by motor proteins is a major contributor to tissue remodeling of synovial membrane and joint tissue destruction in rheumatoid arthritis (RA) by promoting infiltration of blood vessels, bone erosion, and loss of cartilage by phagocytes. In this study, we identified that specific glycan processing enzymes are upregulated in certain cell types (fibroblast or endothelial cells) that function in destructive tissue remodeling in rheumatoid arthritis compared to osteoarthritis (OA). TMEM230 was identified as a regulator in the secretion of metaloproteinases and heparanase necessary tissue remodeling in OA and RA. In dendritic (DC), natural killer and T cells, TMEM230 was expressed at low or no levels in RA compared to OA. TMEM230 expression in DC likely is necessary for regulatory or helper T cells to maintain tolerance to self-antigens and prevent susceptibility to autoimmune disease. To identify how TMEM230 and the endomembrane system contribute to autoimmunity we investigated, glycan modifying enzymes, metalloproteinases and motor protein genes co-regulated with or regulated by TMEM230 in synovial tissue by analyzing published single cell transcriptomic datasets from RA patient derived synovial tissue.


Assuntos
Metaloproteínas , Humanos , Metaloproteínas/metabolismo , Metaloproteínas/genética , Análise de Célula Única , Autoimunidade , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Animais , Perfilação da Expressão Gênica
7.
Adv Protein Chem Struct Biol ; 141: 331-360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38960479

RESUMO

We recently identified TMEM230 as a master regulator of the endomembrane system of cells. TMEM230 expression is necessary for promoting motor protein dependent intracellular trafficking of metalloproteins for cellular energy production in mitochondria. TMEM230 is also required for transport and secretion of metalloproteinases for autophagy and phagosome dependent clearance of misfolded proteins, defective RNAs and damaged cells, activities that decline with aging. This suggests that aberrant levels of TMEM230 may contribute to aging and regain of proper levels may have therapeutic applications. The components of the endomembrane system include the Golgi complex, other membrane bound organelles, and secreted vesicles and factors. Secreted cellular components modulate immune response and tissue regeneration in aging. Upregulation of intracellular packaging, trafficking and secretion of endosome components while necessary for tissue homeostasis and normal wound healing, also promote secretion of pro-inflammatory and pro-senescence factors. We recently determined that TMEM230 is co-regulated with trafficked cargo of the endomembrane system, including lysosome factors such as RNASET2. Normal tissue regeneration (in aging), repair (following injury) and aberrant destructive tissue remodeling (in cancer or autoimmunity) likely are regulated by TMEM230 activities of the endomembrane system, mitochondria and autophagosomes. The role of TMEM230 in aging is supported by its ability to regulate the pro-inflammatory secretome and senescence-associated secretory phenotype in tissue cells of patients with advanced age and chronic disease. Identifying secreted factors regulated by TMEM230 in young patients and patients of advanced age will facilitate identification of aging associated targets that aberrantly promote, inhibit or reverse aging. Ex situ culture of patient derived cells for identifying secreted factors in tissue regeneration and aging provides opportunities in developing therapeutic and personalized medicine strategies. Identification and validation of human secreted factors in tissue regeneration requires long-term stabile scaffold culture conditions that are different from those previously reported for cell lines used as cell models for aging. We describe a 3 dimensional (3D) platform utilizing non-biogenic and non-labile poly ε-caprolactone scaffolds that supports maintenance of long-term continuous cultures of human stem cells, in vitro generated 3D organoids and patient derived tissue. Combined with animal component free culture media, non-biogenic scaffolds are suitable for proteomic and glycobiological analyses to identify human factors in aging. Applications of electrospun nanofiber technologies in 3D cell culture allow for ex situ screening and the development of patient personalized therapeutic strategies and predicting their effectiveness in mitigating or promoting aging.


Assuntos
Envelhecimento , Organoides , Humanos , Organoides/metabolismo , Envelhecimento/metabolismo , Proteínas de Membrana/metabolismo , Senescência Celular , Feminino , Alicerces Teciduais/química , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/citologia
8.
PNAS Nexus ; 2(6): pgad170, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37346271

RESUMO

The expanding field of precision gene editing using CRISPR/Cas9 has demonstrated its potential as a transformative technology in the treatment of various diseases. However, whether this genome-editing tool could be used to modify neural circuits in the central nervous system (CNS), which are implicated in complex behavioral traits, remains uncertain. In this study, we demonstrate the feasibility of noninvasive, intranasal delivery of adeno-associated virus serotype 9 (AAV9) vectors containing CRISPR/Cas9 cargo within the CNS resulting in modification of the HTR2A receptor gene. In vitro, exposure to primary mouse cortical neurons to AAV9 vectors targeting the HT2RA gene led to a concentration-dependent decrease in spontaneous electrical activity following multielectrode array (MEA) analysis. In vivo, at 5 weeks postintranasal delivery in mice, analysis of brain samples revealed single base pair deletions and nonsense mutations, leading to an 8.46-fold reduction in mRNA expression and a corresponding 68% decrease in the 5HT-2A receptor staining. Our findings also demonstrate a significant decrease in anxiety-like behavior in treated mice. This study constitutes the first successful demonstration of a noninvasive CRISPR/Cas9 delivery platform, capable of bypassing the blood-brain barrier and enabling modulation of neuronal 5HT-2A receptor pathways. The results of this study targeting the HTR2A gene provide a foundation for the development of innovative therapeutic strategies for a broad range of neurological disorders, including anxiety, depression, attentional deficits, and cognitive dysfunction.

9.
Front Cell Neurosci ; 15: 703431, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867197

RESUMO

Glioblastomas (GBM) are the most aggressive tumors originating in the brain. Histopathologic features include circuitous, disorganized, and highly permeable blood vessels with intermittent blood flow. These features contribute to the inability to direct therapeutic agents to tumor cells. Known targets for anti-angiogenic therapies provide minimal or no effect in overall survival of 12-15 months following diagnosis. Identification of novel targets therefore remains an important goal for effective treatment of highly vascularized tumors such as GBM. We previously demonstrated in zebrafish that a balanced level of expression of the transmembrane protein TMEM230/C20ORF30 was required to maintain normal blood vessel structural integrity and promote proper vessel network formation. To investigate whether TMEM230 has a role in the pathogenesis of GBM, we analyzed its prognostic value in patient tumor gene expression datasets and performed cell functional analysis. TMEM230 was found necessary for growth of U87-MG cells, a model of human GBM. Downregulation of TMEM230 resulted in loss of U87 migration, substratum adhesion, and re-passaging capacity. Conditioned media from U87 expressing endogenous TMEM230 induced sprouting and tubule-like structure formation of HUVECs. Moreover, TMEM230 promoted vascular mimicry-like behavior of U87 cells. Gene expression analysis of 702 patients identified that TMEM230 expression levels distinguished high from low grade gliomas. Transcriptomic analysis of patients with gliomas revealed molecular pathways consistent with properties observed in U87 cell assays. Within low grade gliomas, elevated TMEM230 expression levels correlated with reduced overall survival independent from tumor subtype. Highest level of TMEM230 correlated with glioblastoma and ATP-dependent microtubule kinesin motor activity, providing a direction for future therapeutic intervention. Our studies support that TMEM230 has both glial tumor and endothelial cell intracellular and extracellular functions. Elevated levels of TMEM230 promote glial tumor cell migration, extracellular scaffold remodeling, and hypervascularization and abnormal formation of blood vessels. Downregulation of TMEM230 expression may inhibit both low grade glioma and glioblastoma tumor progression and promote normalization of abnormally formed blood vessels. TMEM230 therefore is both a promising anticancer and antiangiogenic therapeutic target for inhibiting GBM tumor cells and tumor-driven angiogenesis.

10.
Genetics ; 181(4): 1415-25, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19189955

RESUMO

A comprehensive genetic linkage map of the domestic cat X chromosome was generated with the goal of localizing the genomic position of the classic X-linked orange (O) locus. Microsatellite markers with an average spacing of 3 Mb were selected from sequence traces of the cat 1.9x whole genome sequence (WGS), including the pseudoautosomal region 1 (PAR1). Extreme variation in recombination rates (centimorgans per megabase) was observed along the X chromosome, ranging from a virtual absence of recombination events in a region estimated to be >30 Mb to recombination frequencies of 15.7 cM/Mb in a segment estimated to be <0.3 Mb. This detailed linkage map was applied to position the X-linked orange gene, placing this locus on the q arm of the X chromosome, as opposed to a previously reported location on the p arm. Fine mapping placed the locus between markers at positions 106 and 116.8 Mb in the current 1.9x-coverage sequence assembly of the cat genome. Haplotype analysis revealed potential recombination events that could reduce the size of the candidate region to 3.5 Mb and suggested multiple origins for the orange phenotype in the domestic cat. Furthermore, epistasis of orange over nonagouti was demonstrated at the genetic level.


Assuntos
Proteína Agouti Sinalizadora/genética , Gatos/genética , Epistasia Genética/fisiologia , Evolução Molecular , Cor de Cabelo/genética , Cromossomo X/genética , Animais , Mapeamento Cromossômico , Genética Populacional , Repetições de Microssatélites , Locos de Características Quantitativas
11.
Lab Anim (NY) ; 38(6): 202-10, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19455166

RESUMO

The animal research community faces a shortage of surgical training opportunities along with an increasing demand for expertise in surgical techniques. One possible means of overcoming this challenge is the use of computer-based or electronic learning (e-learning) to disseminate material to a broad range of animal users. E-learning platforms can take many different forms, ranging from simple text documents that are posted online to complex virtual courses that incorporate dynamic video or audio content and in which students and instructors can interact in real time. The authors present an overview of e-learning and discuss its potential benefits as a supplement to hands-on rodent surgical training. They also discuss a few basic considerations in developing and implementing electronic courses.


Assuntos
Animais de Laboratório/cirurgia , Instrução por Computador/métodos , Ciência dos Animais de Laboratório/educação , Cirurgia Veterinária/educação , Animais , Currículo , Humanos
12.
Lab Anim (NY) ; 38(9): 295-304, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19701180

RESUMO

The animal research community comprises members from a wide variety of backgrounds, some of whom must learn basic surgical skills. Though demand for animal research personnel who have surgical skills is increasing, surgical training opportunities are becoming more scarce. Electronic learning or e-learning platforms can be used as an adjunct to hands-on surgical training. Course developers can adapt these e-learning courses to fit the needs of participants who have varying levels of expertise. The authors outline the steps involved in developing an effective e-learning surgical course. They also describe how to use various equipment and software products to help implement e-learning courses. Though the authors focus on developing surgical courses, course developers could apply the general steps outlined by the authors when developing any e-learning course.


Assuntos
Animais de Laboratório/cirurgia , Instrução por Computador/métodos , Cirurgia Geral/educação , Animais , Humanos
13.
Methods Enzymol ; 418: 284-307, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17141042

RESUMO

Embryonic stem cells (ESCs), derivatives of totipotential cells of early mammalian embryos, have proven to be one of the most powerful tools for studying developmental and stem cell biology. When injected into embryos, ESCs can contribute to tissues derived from all three germ layers and to the germ line. Prior studies have successfully shown that ESCs can recapitulate features of embryonic development by spontaneously forming somatic lineages in culture. More recent studies using differentiating monolayer cultures and embryoid bodies have shown that mouse ESCs can also form germ cells that are capable of undergoing meiosis and forming both male and female gametes. This chapter provides detailed instruction on how to differentiate ESCs in monolayer cultures to derive germ cells and oocyte-like structures and presents standard methodologies for detecting expression of key genetic pathways required for primordial germ cell (PGC) development and oogenesis in vivo. While the full potential of these ESC-derived germ cells and oocyte-like structures remains to be demonstrated, this assay provides a new approach to studying reproductive developmental biology in vitro.


Assuntos
Oócitos/citologia , Oócitos/fisiologia , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Separação Celular/métodos , Meios de Cultura , Desenvolvimento Embrionário , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Feminino , Fibroblastos/citologia , Regulação da Expressão Gênica , Mamíferos , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Semin Reprod Med ; 23(3): 222-33, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16059828

RESUMO

Embryonic stem (ES) cells, derivatives of cells of early mammalian embryos, have turned out to be one of the most powerful tools in developmental and stem cell biology. When injected into embryos, ES cells can contribute to tissues derived from all three germ layers and to the germline. Amazingly, ES cells in culture are able to recapitulate features of embryonic development spontaneously. In addition to previous successes in deriving somatic cell types, recent studies have shown that both mouse and human ES cells can also give rise to primordial germ cells (PGCs) in culture. These mouse germ cells appear to be capable of undergoing meiosis and forming both male and female gametes. Although the full function of these ES-derived germ cells and gametes remains to be demonstrated, these findings open the door for undertaking new types of reproductive studies and novel approaches in regenerative medicine.


Assuntos
Embrião de Mamíferos/citologia , Oócitos/fisiologia , Espermatozoides/fisiologia , Células-Tronco/fisiologia , Animais , Feminino , Marcadores Genéticos , Humanos , Masculino , Oócitos/crescimento & desenvolvimento , Reprodução/genética , Espermatozoides/crescimento & desenvolvimento
15.
G3 (Bethesda) ; 4(10): 1881-91, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25085922

RESUMO

The Dominant White locus (W) in the domestic cat demonstrates pleiotropic effects exhibiting complete penetrance for absence of coat pigmentation and incomplete penetrance for deafness and iris hypopigmentation. We performed linkage analysis using a pedigree segregating White to identify KIT (Chr. B1) as the feline W locus. Segregation and sequence analysis of the KIT gene in two pedigrees (P1 and P2) revealed the remarkable retrotransposition and evolution of a feline endogenous retrovirus (FERV1) as responsible for two distinct phenotypes of the W locus, Dominant White, and white spotting. A full-length (7125 bp) FERV1 element is associated with white spotting, whereas a FERV1 long terminal repeat (LTR) is associated with all Dominant White individuals. For purposes of statistical analysis, the alternatives of wild-type sequence, FERV1 element, and LTR-only define a triallelic marker. Taking into account pedigree relationships, deafness is genetically linked and associated with this marker; estimated P values for association are in the range of 0.007 to 0.10. The retrotransposition interrupts a DNAase I hypersensitive site in KIT intron 1 that is highly conserved across mammals and was previously demonstrated to regulate temporal and tissue-specific expression of KIT in murine hematopoietic and melanocytic cells. A large-population genetic survey of cats (n = 270), representing 30 cat breeds, supports our findings and demonstrates statistical significance of the FERV1 LTR and full-length element with Dominant White/blue iris (P < 0.0001) and white spotting (P < 0.0001), respectively.


Assuntos
Retrovirus Endógenos/genética , Pigmentação/genética , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Cruzamento , Gatos , Ligação Genética , Genética Populacional , Genótipo , Perda Auditiva/patologia , Perda Auditiva/veterinária , Células-Tronco Hematopoéticas/metabolismo , Íntrons , Mastócitos/metabolismo , Linhagem , Fenótipo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Retroelementos/genética , Análise de Sequência de RNA , Sequências Repetidas Terminais/genética
16.
J Am Assoc Lab Anim Sci ; 52(6): 711-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24351758

RESUMO

Personnel working with laboratory animals are required by laws and guidelines to be trained and qualified to perform biomethodologic procedures. The assessment of competency and proficiency is a vital component of a laboratory animal training program, because this process confirms that the trainees have met the learning objectives for a particular procedure. The approach toward qualification assessment differs between organizations because laws and guidelines do not outline how the assessment should be performed or which methods and tools should be used. Assessment of clinical and surgical medicine has received considerable attention over the last few decades and has progressed from simple subjective methods to well-defined and objective methods of assessing competency. Although biomethodology competency and proficiency assessment is discussed in the literature, a standard and objective assessment method has not yet been developed. The development and implementation of an objective and standardized biomethodologic assessment program can serve as a tool to improve standards, ensure consistent training, and decrease research variables yet ensure animal welfare. Here we review the definition and goals of training and assessment, review assessment methods, and propose a method to develop a standard and objective assessment program for the laboratory animal science field, particularly training departments and IACUC.


Assuntos
Ciência dos Animais de Laboratório/educação , Comitês de Cuidado Animal , Bem-Estar do Animal , Animais , Animais de Laboratório , Ciência dos Animais de Laboratório/normas
17.
Stem Cell Reports ; 1(4): 336-49, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24319668

RESUMO

Understanding BRCA1 mutant cancers is hampered by difficulties in obtaining primary cells from patients. We therefore generated and characterized 24 induced pluripotent stem cell (iPSC) lines from fibroblasts of eight individuals from a BRCA1 5382insC mutant family. All BRCA1 5382insC heterozygous fibroblasts, iPSCs, and teratomas maintained equivalent expression of both wild-type and mutant BRCA1 transcripts. Although no difference in differentiation capacity was observed between BRCA1 wild-type and mutant iPSCs, there was elevated protein kinase C-theta (PKC-theta) in BRCA1 mutant iPSCs. Cancer cell lines with BRCA1 mutations and hormone-receptor-negative breast cancers also displayed elevated PKC-theta. Genome sequencing of the 24 iPSC lines showed a similar frequency of reprogramming-associated de novo mutations in BRCA1 mutant and wild-type iPSCs. These data indicate that iPSC lines can be derived from BRCA1 mutant fibroblasts to study the effects of the mutation on gene expression and genome stability.


Assuntos
Proteína BRCA1/genética , Linhagem Celular , Mutação , Proteína BRCA1/metabolismo , Diferenciação Celular , Células Cultivadas , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Genoma Humano , Heterozigoto , Humanos , Células-Tronco Pluripotentes Induzidas , Isoenzimas/genética , Isoenzimas/metabolismo , Linhagem , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteína Quinase C-theta , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Teratoma/genética , Teratoma/metabolismo
18.
Lab Anim ; 45(4): 231-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21828079

RESUMO

The refinement of surgical techniques represents a key opportunity to improve the welfare of laboratory rodents, while meeting legal and ethical obligations. Current methods used for monitoring intra-abdominal disease progression in rodents usually involve euthanasia at various time-points for end of study, one-time individual tissue collections. Most rodent organ tumour models are developed by the introduction of tumour cells via laparotomy or via ultrasound-guided indirect visualization. Ischaemic rodent models are often generated using laparotomies. This approach requires a high number of rodents, and in some instances introduces high degrees of morbidity and mortality, thereby increasing study variability and expense. Most importantly, most laparotomies do not promote the highest level of rodent welfare. Recent improvements in laparoscopic equipment and techniques have enabled the adaptation of laparoscopy for rodent procedures. Laparoscopy, which is considered the gold standard for many human abdominal procedures, allows for serial biopsy collections from the same animal, results in decreased pain and tissue trauma as well as quicker postsurgical recovery, and preserves immune function in comparison to the same procedures performed by laparotomy. Laparoscopy improves rodent welfare, decreases inter-animal variability, thereby reducing the number of required animals, allows for the replacement of larger species, decreases expense and improves data yield. This review article compares rodent laparotomy and laparoscopic surgical methods, and describes the utilization of laparoscopy for the development of cancer models and assessment of disease progression to improve data collection and animal welfare. In addition, currently available rodent laparoscopic equipment and instrumentation are presented.


Assuntos
Bem-Estar do Animal , Animais de Laboratório , Laparoscopia/instrumentação , Laparoscopia/métodos , Laparotomia/métodos , Monitorização Fisiológica/métodos , Roedores , Animais
19.
J Am Assoc Lab Anim Sci ; 49(3): 307-11, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20587161

RESUMO

The development of new rodent models of human disease and advances in surgical equipment and technologies have increased the demand for expertise in rodent surgery. Because of the limited availability of rodent surgical training courses, electronic (e-) learning is presented as an alternative to in-person education and as a means to hone the expertise of current surgeons in biomedical research, similar to e-learning applications for human surgery training. Translating this model to the biomedical research field provides participants with an opportunity to train themselves on rodent surgical techniques prior to operating on live models. An e-learning rodent surgery course was incorporated into a training class of undergraduate (n = 39) and graduate (n = 12) laboratory animal students, and a portion of the course was presented to laboratory animal professionals (n = 15). The effectiveness of the method was evaluated using written examination and postcourse surveys. The exam data demonstrated that the e-learning course transferred knowledge comparable to a lecture course on surgery that was presented in-person. Students responded favorably to videos, step-by-step photographs of surgical procedures, and the ready accessibility of the course. Critiques included the need to improve video resolution and quality of the voice-overs. These results support the continued development and implementation of electronic rodent surgical technique courses for use in laboratory animal and biomedical research communities.


Assuntos
Instrução por Computador/métodos , Cirurgia Geral/educação , Multimídia , Roedores/cirurgia , Animais , Internet
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