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1.
Sci Rep ; 14(1): 8963, 2024 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637564

RESUMEN

The health of honey bee queens is crucial for colony success, particularly during stressful periods like overwintering. To accompany a previous longitudinal study of colony and worker health, we explored niche-specific gut microbiota, host gene expression, and pathogen prevalence in honey bee queens overwintering in a warm southern climate. We found differential gene expression and bacterial abundance with respect to various pathogens throughout the season. Biologically older queens had larger microbiotas, particularly enriched in Bombella and Bifidobacterium. Both Deformed Wing Virus A and B subtypes were highest in the fat body tissue in January, correlating with colony Varroa levels, and Deformed Wing Virus titers in workers. High viral titers in queens were associated with decreased vitellogenin expression, suggesting a potential trade-off between immune function and reproductive capacity. Additionally, we found a complex and dynamic relationship between these viral loads and immune gene expression, indicating a possible breakdown in the coordinated immune response as the season progressed. Our study also revealed a potential link between Nosema and Melissococcus plutonius infections in queens, demonstrating that seasonal opportunism is not confined to just workers. Overall, our findings highlight the intricate interplay between pathogens, metabolic state, and immune response in honey bee queens. Combined with worker and colony-level metrics from the same colonies, our findings illustrate the social aspect of queen health and resilience over the winter dearth.


Asunto(s)
Clima , Virus ARN , Abejas , Animales , Estaciones del Año , Estudios Longitudinales
2.
Bioessays ; : e2400021, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528317

RESUMEN

The T/t locus was a major focus of study by mouse geneticists during the 20th century. In the 70s, as the study of cell surface antigens controlling transplantation antigens was taking off, several laboratories hypothesized that alleles of this locus would control cell surface antigens important for embryonic development. One such antigen, the embryonal carcinoma F9 antigen was said to be an example. Other antigens were described on sperm and embryos that were said to be controlled by alleles at the T/t complex. These findings were later found to be false. The history of the findings and their refutation is described.

3.
Sci Rep ; 14(1): 1954, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263184

RESUMEN

Probiotics are widely used in agriculture including commercial beekeeping, but there is little evidence supporting their effectiveness. Antibiotic treatments can greatly distort the gut microbiome, reducing its protective abilities and facilitating the growth of antibiotic resistant pathogens. Commercial beekeepers regularly apply antibiotics to combat bacterial infections, often followed by an application of non-native probiotics advertised to ease the impact of antibiotic-induced gut dysbiosis. We tested whether probiotics affect the gut microbiome or disease prevalence, or rescue the negative effects of antibiotic induced gut dysbiosis. We found no difference in the gut microbiome or disease markers by probiotic application or antibiotic recovery associated with probiotic treatment. A colony-level application of the antibiotics oxytetracycline and tylosin produced an immediate decrease in gut microbiome size, and over the longer-term, very different and persistent dysbiotic effects on the composition and membership of the hindgut microbiome. Our results demonstrate the lack of probiotic effect or antibiotic rescue, detail the duration and character of dysbiotic states resulting from different antibiotics, and highlight the importance of the gut microbiome for honeybee health.


Asunto(s)
Oxitetraciclina , Probióticos , Abejas , Animales , Disbiosis , Antibacterianos , Tilosina
4.
SAGE Open Med Case Rep ; 11: 2050313X231194507, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37654545

RESUMEN

A 77-year-old woman had 2 weeks of fever and flu-like symptoms starting several hours after receiving an mRNA booster for SARS-CoV-2 and the influenza vaccine, in separate shots. Laboratory tests showed cholangitis. Medical history included APOE-ε4 carrier genotype, mild Alzheimer's disease, participation in a clinical trial of aducanumab, and resolving polymyalgia rheumatica. The patient recovered with at-home supportive care. She had aducanumab-associated amyloid-related imaging abnormalities-edema (ARIA-E) both before and after the acute cholangitis. Two months following the vaccinations polymyalgia rheumatica recurred. This case raises questions about interactions among immune-mediated disease, complications of anti-amyloid monoclonal antibodies, and adverse events following SARS-CoV-2 mRNA vaccination.

5.
Dev Biol ; 499: 22-23, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37149123
6.
Sci Rep ; 13(1): 1162, 2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36670153

RESUMEN

As essential pollinators of ecosystems and agriculture, honey bees (Apis mellifera) are host to a variety of pathogens that result in colony loss. Two highly prevalent larval diseases are European foulbrood (EFB) attributed to the bacterium Melissococcus plutonius, and Varroosis wherein larvae can be afflicted by one or more paralytic viruses. Here we used high-throughput sequencing and qPCR to detail microbial succession of larval development from six diseased, and one disease-free apiary. The disease-free larval microbiome revealed a variety of disease-associated bacteria in early larval instars, but later developmental stages were dominated by beneficial symbionts. Microbial succession associated with EFB pathology differed by apiary, characterized by associations with various gram-positive bacteria. At one apiary, diseased larvae were uniquely described as "melting and deflated", symptoms associated with Varroosis. We found that Acute Bee Paralysis Virus (ABPV) levels were significantly associated with these symptoms, and various gram-negative bacteria became opportunistic in the guts of ABPV afflicted larvae. Perhaps contributing to disease progression, the ABPV associated microbiome was significantly depleted of gram-positive bacteria, a likely result of recent antibiotic application. Our results contribute to the understanding of brood disease diagnosis and treatment, a growing problem for beekeeping and agriculture worldwide.


Asunto(s)
Bacterias , Ecosistema , Abejas , Animales , Larva/microbiología , Bacterias Grampositivas , Apicultura
7.
Cerebellum ; 22(1): 102-119, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35040097

RESUMEN

Selective neuronal vulnerability is common to most degenerative disorders, including Niemann-Pick C (NPC), a rare genetic disease with altered intracellular trafficking of cholesterol. Purkinje cell dysfunction and loss are responsible for cerebellar ataxia, which is among the prevailing neurological signs of the NPC disease. In this review, we focus on some questions that are still unresolved. First, we frame the cerebellar vulnerability in the context of the extended postnatal time length by which the development of this structure is completed in mammals. In line with this thought, the much later development of cerebellar symptoms in humans is due to the later development and/or maturation of the cerebellum. Hence, the occurrence of developmental events under a protracted condition of defective intracellular cholesterol mobilization hits the functional maturation of the various cell types generating the ground of increased vulnerability. This is particularly consistent with the high cholesterol demand required for cell proliferation, migration, differentiation, and synapse formation/remodeling. Other major questions we address are why the progression of Purkinje cells loss is always from the anterior to the posterior lobes and why cerebellar defects persist in the mouse model even when genetic manipulations can lead to nearly normal survival.


Asunto(s)
Enfermedad de Niemann-Pick Tipo C , Masculino , Ratones , Animales , Humanos , Enfermedad de Niemann-Pick Tipo C/genética , Cerebelo/metabolismo , Células de Purkinje/metabolismo , Neuronas/metabolismo , Colesterol/metabolismo , Mamíferos
8.
J Appl Genet ; 64(1): 141-144, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36175752

RESUMEN

Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked, known as IPEX syndrome, is a rare heterogeneous condition. Zhu-Tokita-Takenouchi-Kim Syndrome (ZTTK) is an autosomal dominant condition arising from a mutation in the SON gene, which is involved in mRNA splicing. A case showing interactions of mutations in these two genes is described in which both conditions become non-typical.


Asunto(s)
Enfermedades Genéticas Ligadas al Cromosoma X , Enfermedades Intestinales , Poliendocrinopatías Autoinmunes , Humanos , Poliendocrinopatías Autoinmunes/diagnóstico , Poliendocrinopatías Autoinmunes/genética , Síndrome , Enfermedades Intestinales/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Mutación , Factores de Transcripción Forkhead/genética
9.
J Appl Genet ; 63(3): 469-474, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35508755

RESUMEN

Niemann-Pick C disease frequently presents as severe cholestatic disease in infants. However, it progressively becomes less of a problem as children age. We have found that, in an appropriate mouse model, liver cholesterol levels, which are initially very high, decrease while mitochondrial function, initially quite compromised, increases with age. The key mitochondrial regulator, MNRR1, increases in parallel with the increase in mitochondrial function. These changes appear to explain the amelioration of the liver disease that occurs with time in this disorder.


Asunto(s)
Hígado , Enfermedad de Niemann-Pick Tipo C , Animales , Modelos Animales de Enfermedad , Humanos , Ratones , Enfermedad de Niemann-Pick Tipo C/genética
10.
Am J Med ; 135(2): e31-e41, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34656527

RESUMEN

BACKGROUND: The lymphatic system is essential for maintaining the balance of interstitial fluid in tissues and for returning protein-rich fluids (lymph) to the bloodstream. Congenital lymphatic defects lead to accumulation of lymph in peripheral tissues and body cavities, termed primary lymphedema. To date, only a limited number of individual genes have been identified in association with primary lymphedema. However, variability of age of onset and severity of lymphatic abnormalities within some families suggests that multiple mutations or genes may be responsible, thus hampering efforts to identify individual associated genes. METHODS: Whole exome sequencing (WES) was performed in 4 members of a large multigeneration family with highly variable lymphedema and followed by Sanger sequencing for identified mutations in 34 additional family members. Genotypes were correlated with clinical and lymphangioscintigraphic phenotypes. RESULTS: WES uncovered 2 different mechanotransducer PIEZO1 mutations and one FOXC2 transcription factor mutation in various combinations. Sanger sequencing confirmed the presence/absence of the 3 variants in affected and unaffected family members and co-segregation of one or more variants with disease. Genetic profiles did not clearly correlate with the highly variable severity of lymphatic abnormalities. CONCLUSIONS: WES in lymphedema families can uncover unexpected combinations of several lymphedema-associated mutations. These findings provide essential information for genetic counseling and reveal complex gene interactions in lymphatic developmental pathways. These can offer insights into the complex spectrum of clinical and lymphatic lymphedema phenotypes and potential targets for treatment.


Asunto(s)
Factores de Transcripción Forkhead/genética , Predisposición Genética a la Enfermedad , Canales Iónicos/genética , Linfedema/genética , Familia , Femenino , Ligamiento Genético , Humanos , Linfedema/patología , Masculino , Mutación , Linaje
11.
Viruses ; 15(1)2022 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-36680136

RESUMEN

From July−November 2020, mink (Neogale vison) on 12 Utah farms experienced an increase in mortality rates due to confirmed SARS-CoV-2 infection. We conducted epidemiologic investigations on six farms to identify the source of virus introduction, track cross-species transmission, and assess viral evolution. Interviews were conducted and specimens were collected from persons living or working on participating farms and from multiple animal species. Swabs and sera were tested by SARS-CoV-2 real-time reverse transcription polymerase chain reaction (rRT-PCR) and serological assays, respectively. Whole genome sequencing was attempted for specimens with cycle threshold values <30. Evidence of SARS-CoV-2 infection was detected by rRT-PCR or serology in ≥1 person, farmed mink, dog, and/or feral cat on each farm. Sequence analysis showed high similarity between mink and human sequences on corresponding farms. On farms sampled at multiple time points, mink tested rRT-PCR positive up to 16 weeks post-onset of increased mortality. Workers likely introduced SARS-CoV-2 to mink, and mink transmitted SARS-CoV-2 to other animal species; mink-to-human transmission was not identified. Our findings provide critical evidence to support interventions to prevent and manage SARS-CoV-2 in people and animals on mink farms and emphasizes the importance of a One Health approach to address emerging zoonoses.


Asunto(s)
COVID-19 , Salud Única , Animales , Humanos , Gatos , Perros , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/veterinaria , Visón , Granjas , Utah/epidemiología
12.
Nat Rev Dis Primers ; 7(1): 77, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34675250

RESUMEN

Lymphoedema is the swelling of one or several parts of the body owing to lymph accumulation in the extracellular space. It is often chronic, worsens if untreated, predisposes to infections and causes an important reduction in quality of life. Primary lymphoedema (PLE) is thought to result from abnormal development and/or functioning of the lymphatic system, can present in isolation or as part of a syndrome, and can be present at birth or develop later in life. Mutations in numerous genes involved in the initial formation of lymphatic vessels (including valves) as well as in the growth and expansion of the lymphatic system and associated pathways have been identified in syndromic and non-syndromic forms of PLE. Thus, the current hypothesis is that most cases of PLE have a genetic origin, although a causative mutation is identified in only about one-third of affected individuals. Diagnosis relies on clinical presentation, imaging of the structure and functionality of the lymphatics, and in genetic analyses. Management aims at reducing or preventing swelling by compression therapy (with manual drainage, exercise and compressive garments) and, in carefully selected cases, by various surgical techniques. Individuals with PLE often have a reduced quality of life owing to the psychosocial and lifelong management burden associated with their chronic condition. Improved understanding of the underlying genetic origins of PLE will translate into more accurate diagnosis and prognosis and personalized treatment.


Asunto(s)
Linfedema , Calidad de Vida , Drenaje , Humanos , Recién Nacido , Linfedema/etiología , Linfedema/genética
13.
J Appl Genet ; 62(3): 445-453, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33880741

RESUMEN

The peopling of the Americas by Native Americans occurred in 4 waves of which the last was Nadene language speakers of whom Athabaskans are the largest group. As the Europeans were entering the Southwestern states of the USA, Athabaskan hunting-gathering tribes were migrating South from Canada along the Rocky Mountains and undergoing potential bottlenecks reflected in autosomal recessive diseases shared by Apaches and Navajos. About 300 years ago, the Navajo developing a sedentary culture learned from Pueblo Indians while the Apache remained hunter-gathers. Although most of the tribe was rounded up and forced to relocate to Bosque Redondo, the adult breeding population was large enough to prevent a genetic bottleneck. However, some Navajo underwent further population bottlenecks while hiding from the brutal US Army action (under Kit Carson's guidance). This led to an increased frequency of other autosomal recessive diseases. Recent advances in population genetics, pathophysiology of the diseases, and social/ethical issues concerning their study are reviewed.


Asunto(s)
Enfermedades Genéticas Congénitas/etnología , Indígenas Norteamericanos , Adulto , Genes Recesivos , Genética de Población , Humanos , Indígenas Norteamericanos/genética , Lenguaje , Sudoeste de Estados Unidos
14.
Zootaxa ; 4934(1): zootaxa.4934.1.1, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33756770

RESUMEN

We describe the Cephalozygoptera, a new, extinct suborder of Odonata, composed of the families Dysagrionidae and Sieblosiidae, previously assigned to the Zygoptera, and possibly the Whetwhetaksidae n. fam. The Cephalozygoptera is close to the Zygoptera, but differs most notably by distinctive head morphology. It includes 59 to 64 species in at least 19 genera and one genus-level parataxon. One species is known from the Early Cretaceous (Congqingia rhora Zhang), possibly three from the Paleocene, and the rest from the early Eocene through late Miocene. We describe new taxa from the Ypresian Okanagan Highlands of British Columbia, Canada and Washington, United States of America: 16 new species of Dysagrionidae of the existing genus Dysagrion (D. pruettae); the new genera Okanagrion (O. threadgillae, O. hobani, O. beardi, O. lochmum, O. angustum, O. dorrellae, O. liquetoalatum, O. worleyae, all new species); Okanopteryx (O. jeppesenorum, O. fraseri, O. macabeensis, all new species); Stenodiafanus (S. westersidei, new species); the new genus-level parataxon Dysagrionites (D. delinei new species, D. sp. A, D. sp. B, both new); and one new genus and species of the new family Whetwhetaksidae (Whetwhetaksa millerae).


Asunto(s)
Odonata , Animales , América del Norte
15.
Mol Phylogenet Evol ; 160: 107115, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33609713

RESUMEN

Dragonflies and damselflies are a charismatic, medium-sized insect order (~6300 species) with a unique potential to approach comparative research questions. Their taxonomy and many ecological traits for a large fraction of extant species are relatively well understood. However, until now, the lack of a large-scale phylogeny based on high throughput data with the potential to connect both perspectives has precluded comparative evolutionary questions for these insects. Here, we provide an ordinal hypothesis of classification based on anchored hybrid enrichment using a total of 136 species representing 46 of the 48 families or incertae sedis, and a total of 478 target loci. Our analyses recovered the monophyly for all three suborders: Anisoptera, Anisozygoptera and Zygoptera. Although the backbone of the topology was reinforced and showed the highest support values to date, our genomic data was unable to stronglyresolve portions of the topology. In addition, a quartet sampling approach highlights the potential evolutionary scenarios that may have shaped evolutionary phylogeny (e.g., incomplete lineage sorting and introgression) of this taxon. Finally, in light of our phylogenomic reconstruction and previous morphological and molecular information we proposed an updated odonate classification and define five new families (Amanipodagrionidae fam. nov., Mesagrionidae fam. nov., Mesopodagrionidae fam. nov., Priscagrionidae fam. nov., Protolestidae fam. nov.) and reinstate another two (Rhipidolestidae stat. res., Tatocnemididae stat. res.). Additionally, we feature the problematic taxonomic groupings for examination in future studies to improve our current phylogenetic hypothesis.


Asunto(s)
Genómica , Odonata/clasificación , Odonata/genética , Filogenia , Animales , Femenino , Masculino
16.
J Appl Genet ; 61(4): 567-570, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32794098

RESUMEN

Niemann-Pick C1 (NPC1) mouse models show neurofibrillary tangles as do human patients. A previous study in NPC1/tau double-null mutant mice showed that tau knockout nulls and heterozygotes unexpectedly had decreased survival when compared with NPC1 single mutants (Pacheco et al., Hum Molec Genetics 18:956-965, 2009). This was done in a null model of NPC1 (Npc1-/-). We have extended these results to a hypomorphic model (Npc1nmf164) and additionally studied tau phosphorylation, which has not been previously done in a tau heterozygote. As before, NPC1/tau double-mutant mice had shortened survival when compared with the NPC1 single mutant. Tau dosage was not affected by the Npc1 mutation. The increased phosphorylation of tau-ser396 previously noted in NPC1 mouse models was also present, but unaffected by the tau knockout, indicating that changes in tau phosphorylation are not the cause of decreased survival in NPC1/tau double mutants. Thus, the reason for shortened survival of NPC1 mouse models with concomitant tau haploinsufficiency is uncertain.


Asunto(s)
Haploinsuficiencia/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Enfermedad de Niemann-Pick Tipo C/genética , Proteínas tau/genética , Animales , Modelos Animales de Enfermedad , Heterocigoto , Humanos , Ratones , Ratones Noqueados , Mutación/genética , Proteína Niemann-Pick C1 , Enfermedad de Niemann-Pick Tipo C/patología , Fosforilación
17.
Sci Rep ; 10(1): 1497, 2020 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-32001749

RESUMEN

Advancements in molecular genetics have revealed that hybridization may be common among plants, animals, and fungi, playing a role in evolutionary dynamics and speciation. While hybridization has been well-documented in pathogenic fungi, the effects of these processes on speciation in fungal lineages with different life histories and ecological niches are largely unexplored. Here we investigated the potential influence of hybridization on the emergence of morphologically and reproductively distinct asexual lichens. We focused on vagrant forms (growing obligately unattached to substrates) within a clade of rock-dwelling, sexually reproducing species in the Rhizoplaca melanophthalma (Lecanoraceae, Ascomycota) species complex. We used phylogenomic data from both mitochondrial and nuclear genomes to infer evolutionary relationships and potential patterns of introgression. We observed multiple instances of discordance between the mitochondrial and nuclear trees, including the clade comprising the asexual vagrant species R. arbuscula, R. haydenii, R. idahoensis, and a closely related rock-dwelling lineage. Despite well-supported phylogenies, we recovered strong evidence of a reticulated evolutionary history using a network approach that incorporates both incomplete lineage sorting and hybridization. These data suggest that the rock-dwelling western North American subalpine endemic R. shushanii is potentially the result of a hybrid speciation event, and introgression may have also played a role in other taxa, including vagrant species R. arbuscula, R. haydenii and R. idahoensis. We discuss the potential roles of hybridization in terms of generating asexuality and novel morphological traits in lichens. Furthermore, our results highlight the need for additional study of reticulate phylogenies when investigating species boundaries and evolutionary history, even in cases with well-supported topologies inferred from genome-scale data.


Asunto(s)
Ascomicetos/genética , Hibridación Genética , Líquenes/genética , Líquenes/microbiología , Ascomicetos/clasificación , Ascomicetos/fisiología , ADN de Hongos/genética , ADN Mitocondrial/genética , Evolución Molecular , Flujo Génico , Especiación Genética , Genoma Fúngico , Líquenes/clasificación , Modelos Genéticos , Montana , Filogenia , Polimorfismo de Nucleótido Simple , Reproducción Asexuada/genética , Utah
18.
Ultrasound Med Biol ; 46(1): 122-136, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31585767

RESUMEN

Focused ultrasound (FUS), in combination with microbubble contrast agents, can be used to transiently open the blood-brain barrier (BBB) to allow intravascular agents to cross into the brain. Often, FUS is carried out in conjunction with magnetic resonance imaging (MRI) to evaluate BBB opening to gadolinium-based MRI contrast agents. Although MRI allows direct visualization of the distribution of gadolinium-based contrast agents in the brain parenchyma, it does not allow measurements of the distribution of other molecules crossing the BBB. Therapeutic molecules (e.g., monoclonal antibodies) are much different in size than MRI contrast agents and have been found to have different distributions in the brain after FUS-mediated BBB opening. In the work described here, we combined in vivo MRI and ex vivo multispectral fluorescence imaging to compare the distributions of MRI contrast and dextran molecules of different molecular weights (3, 70 and 500 kDa) after FUS-mediated BBB opening through a range of ultrasound pressures (0.18-0.46 MPa) in laboratory mice. The volume of brain exposed was calculated from the MRI and fluorescence images and was significantly dependent on both molecular weight and ultrasound pressure. Diffusion coefficients of the different-molecular-weight dextran molecules in the brain parenchyma were also calculated from the fluorescence images and were negatively correlated with the molecular weight of the dextran molecules. The results of this work build on a body of knowledge that is critically important for the FUS technique to be used in clinical delivery of therapeutics to the brain.


Asunto(s)
Barrera Hematoencefálica/diagnóstico por imagen , Sistemas de Liberación de Medicamentos/métodos , Sustancias Macromoleculares/administración & dosificación , Imagen por Resonancia Magnética , Imagen Óptica , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Medios de Contraste , Difusión , Femenino , Sustancias Macromoleculares/farmacocinética , Masculino , Ratones , Ratones Endogámicos C57BL , Imagen Óptica/métodos , Ultrasonografía/métodos
20.
Mitochondrion ; 51: 15-21, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31862414

RESUMEN

It has long been known that there is decreased mitochondrial function in several tissues of Niemann-Pick C1 model mice and cultured cells. These defects contribute to the accumulation of Reactive Oxygen Species (ROS) and tissue damage. It is also well established that there is increased unesterified cholesterol, stored in late endosomes/lysosomes, in many tissues in mutant humans, mouse models, and mutant cultured cells. Using a mouse model with an NPC1 point mutation that is more typical of the most common form of the disease, and highly purified liver mitochondria, we find markedly decreased mitochondrial membrane cholesterol. This is compared to previous reports of increased mitochondrial membrane cholesterol. We also find that, although in wild-type or heterozygous mitochondria cytochrome c oxidase (COX) activity decreases with age as expected, surprisingly, COX activity in homozygous mutant mice improves with age. COX activity is less than half of wild-type amounts in young mutant mice but later reaches wild-type levels while total liver cholesterol is decreasing. Mutant mice also contain a decreased number of mitochondria that are morphologically abnormal. We suggest that the decreased mitochondrial membrane cholesterol is causative for the mitochondrial energy defects. In addition, we find that the mitochondrial stress regulator protein MNRR1 can stimulate NPC1 synthesis and is deficient in mutant mouse livers. Furthermore, the age curve of MNRR1 deficiency paralleled levels of total cholesterol. The role of such altered mitochondria in initiating the abnormal autophagy and neuroinflammation found in NPC1 mouse models is discussed.


Asunto(s)
Membrana Celular/metabolismo , Colesterol/análisis , Proteínas de Unión al ADN/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Mitocondrias Hepáticas/metabolismo , Enfermedad de Niemann-Pick Tipo C/genética , Factores de Transcripción/metabolismo , Animales , Modelos Animales de Enfermedad , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Hígado/metabolismo , Masculino , Ratones , Proteína Niemann-Pick C1 , Enfermedad de Niemann-Pick Tipo C/patología
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