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1.
Mol Psychiatry ; 28(6): 2370-2381, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36721027

RESUMEN

ZBTB18/RP58 (OMIM *608433) is one of the pivotal genes responsible for 1q43q44 microdeletion syndrome (OMIM #612337) and its haploinsufficiency induces intellectual disability. However, the underlying pathological mechanism of ZBTB18/RP58 haploinsufficiency is unknown. In this study, we generated ZBTB18/RP58 heterozygous mice and found that these mutant mice exhibit multiple behavioral deficits, including impairment in motor learning, working memory, and memory flexibility, which are related to behaviors in people with intellectual disabilities, and show no gross abnormalities in their cytoarchitectures but dysplasia of the corpus callosum, which has been reported in certain population of patients with ZBTB18 haploinsufficiency as well as in those with 1q43q44 microdeletion syndrome, indicating that these mutant mice are a novel model of ZBTB18/RP58 haploinsufficiency, which reflects heterozygotic ZBTB18 missense, truncating variants and some phenotypes of 1q43q44 microdeletion syndrome based on ZBTB18/RP58 haploinsufficiency. Furthermore, these mice show glutamatergic synaptic dysfunctions, including a reduced glutamate receptor expression, altered properties of NMDA receptor-mediated synaptic responses, a decreased saturation level of long-term potentiation of excitatory synaptic transmission, and distinct morphological characteristics of the thick-type spines. Therefore, these results suggest that ZBTB18/RP58 haploinsufficiency leads to impaired excitatory synaptic maturation, which in turn results in cognitive dysfunction in ZBTB18 haploinsufficiency.


Asunto(s)
Disfunción Cognitiva , Discapacidad Intelectual , Humanos , Ratones , Animales , Discapacidad Intelectual/genética , Haploinsuficiencia/genética , Cuerpo Calloso , Transmisión Sináptica/genética , Síndrome , Disfunción Cognitiva/genética
2.
Dev Growth Differ ; 65(9): 591-598, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37750430

RESUMEN

Amphibians generally have three types of pigment cells, namely, melanophores (black and brown), xanthophores (yellow and red), and iridophores (iridescent). Single knockout of the tyr, slc2a7, and hps6 genes in Xenopus tropicalis results in the absence of melanophores, xanthophores, and iridophores, respectively. The generation of triple- knockout (3KO) X. tropicalis for these three genes could allow for observation of internal organs without sacrificing the animals, which would be transparent due to the absence of pigments. In this study, we generated 3KO X. tropicalis, which is one of the most widely used model amphibians, through crossing of a slc2a7 single-knockout frog with a tyr and hps6 double-knockout frog, followed by intercrossing of their offspring. The 3KO tadpoles had transparent bodies like the nop mutant and the frogs had translucent bodies. This translucency allowed us to observe the heart, lungs, stomach, liver, and digestive tract through the ventral body skin without surgery. After intravital staining, 3KO X. tropicalis showed much clearer fluorescent signals of mineralized tissues compared with the wild type. These 3KO X. tropicalis provide a useful mutant line for continuous observation of internal organs and fluorescent signals in the body. In particular, such 3KO frogs would revolutionize fluorescence monitoring in transgenic tadpoles and frogs expressing fluorescent proteins.


Asunto(s)
Melanóforos , Pigmentación , Animales , Xenopus/genética , Xenopus laevis , Pigmentación/genética , Piel , Anuros
3.
Dev Growth Differ ; 65(2): 100-108, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36762977

RESUMEN

Some frog species have a unique skeletal element, referred to as the intercalary element (IE), in the joints between the terminal and subterminal phalanges of all digits. IEs are composed of cartilage or connective tissue and have a markedly differ shape than the phalanges. IEs are highly related to the arboreal lifestyle and toe pads. The IE is found only in neobatrachian frogs among anurans, suggesting that it is a novelty of Neobatrachia. IEs are widely distributed among multiple neobatrachian lineages and are found in the suborders Hyloides and Ranoides (the two major clades in Neobatrachia). However, it is unclear whether the IEs found in multiple linages resulted from convergent evolution. Therefore, in this study, we aimed to examine how similar or different the developmental trajectories of the IEs are between Hyloides and Ranoides. To that end, we compared the osteological and histological developmental processes of the IEs of the hyloid frog Dryophytes japonicus and the ranoid frog Zhangixalus schlegelii. Both species shared the same IE-initiation site and level of tissue differentiation around the IE when it began to form in tadpoles, although the IE developments initiated at different stages which were determined by external criteria. These results suggest that similar mechanisms drive IE formation in the digits of both species, supporting the hypothesis that the IEs did not evolve convergently.


Asunto(s)
Anuros , Cartílago , Animales , Filogenia
4.
J Obstet Gynaecol Res ; 49(12): 2811-2816, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37723942

RESUMEN

AIM: Cryoprecipitate (CRYO) is a concentrated preparation of coagulation factors formulated from fresh frozen plasma (FFP), which can replenish coagulation factors rapidly. Preeclampsia (PE) is frequently associated with postpartum hemorrhage (PPH), and the rapid replenishment of coagulation factors is vital in the management. We conducted a retrospective cohort study to determine the efficacy of administering CRYO irrespective of fibrinogen levels in patients with PE who experienced severe PPH. METHODS: Patients with PPH accompanied by PE and those who required red blood cell (RBC) transfusion were included. Cases were divided into two groups: those treated with CRYO (N = 16) and those not treated with CRYO (N = 10). The total transfusion volume, blood loss before and after transfusion initiation, duration of hospitalization, presence of pulmonary edema, and performance of either interventional radiology or hysterectomy were compared. RESULTS: The median fibrinogen levels before transfusion were 2.24 and 2.34 g/L in the CRYO group and the not using group, respectively. Although blood loss before transfusion was comparable between the two groups, blood loss after transfusion was significantly less in the CRYO group (median: 520 vs. 2352 mL, p = 0.015), as well as the total blood loss (median: 2285 vs. 3825 mL, p = 0.005) and total transfusion volume (median: RBC 6 vs. 16 U, p = 0.01, FFP 10 vs. 20 U, p = 0.017). CONCLUSION: Prompt replenishment of coagulation factors using CRYO to patients with PE who experience severe PPH could decrease further bleeding.


Asunto(s)
Fármacos Hematológicos , Hemorragia Posparto , Preeclampsia , Embarazo , Femenino , Humanos , Hemorragia Posparto/terapia , Estudios Retrospectivos , Preeclampsia/terapia , Factores de Coagulación Sanguínea , Fibrinógeno
5.
Dev Growth Differ ; 64(7): 368-378, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36054601

RESUMEN

Observing mineralization is essential for studying skeletal development, maintenance, and regeneration. Calcein and alizarin red have long been used to visualize mineralization in fixed specimens, but this requires the target animals to be sacrificed. However, several intravital bone-staining methods have been developed to visualize mineralized tissues in living animals. These methods have been applied to study fin rays and transparent fishes. Xenopus tropicalis is an excellent experimental animal model for studying bone formation and regeneration because skeletal mineralization begins during the free-living tadpole period, and its regenerative ability changes during metamorphosis. However, intravital bone staining of X. tropicalis has only been reported for tadpoles, and no details on its specificity or appropriate experimental conditions are available. Here, we compared the calcein- and alizarin red S (ARS)-staining methods and optimized these methods for tadpoles and juvenile frogs during and after metamorphosis. Staining with 0.01% ARS yielded acceptable signaling for young tadpoles, whereas calcein either at 0.1 or 0.01% occasionally showed artifactual staining of unmineralized tissues. In addition, 0.1% calcein or 0.1% ARS staining showed a higher signal-to-noise ratio with juvenile frogs compared to staining at 0.01%. We propose the use of 0.01% ARS for tadpoles before stage 61 and 0.1% ARS thereafter for staining mineralized tissues. Using this method, we found that ossification of the neural arches occurred at stage 51 in X. tropicalis. This method enables precise staging and manipulation based on the visualized bone structure.


Asunto(s)
Metamorfosis Biológica , Osteogénesis , Animales , Antraquinonas , Fluoresceínas , Larva , Coloración y Etiquetado , Xenopus
6.
Int J Mol Sci ; 23(18)2022 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-36142844

RESUMEN

We previously reported that lysophosphatidylinositol (LPI) functions as an endogenous agonist of GPR55, a novel cannabinoid receptor. However, the physiological roles of LPI-GPR55 have not yet been elucidated in detail. In the present study, we found that LPI induced morphological changes in GPR55-expressing HEK293 cells. LPI induced the cell rounding of GPR55-expressing HEK293 cells but not of empty-vector-transfected cells. LPI also induced the activation of small GTP-binding protein RhoA and increased stress fiber formation in GPR55-expressing HEK293 cells. The inhibition of RhoA and Rho kinase ROCK by the C3 exoenzyme and the ROCK inhibitor reduced LPI-induced cell rounding and stress fiber formation. These results clearly indicated that the LPI-induced morphological changes and the assembly of the cytoskeletons were mediated through the GPR55-RhoA-ROCK pathway.


Asunto(s)
Receptores Acoplados a Proteínas G , Quinasas Asociadas a rho , Células HEK293 , Humanos , Lisofosfolípidos/metabolismo , Receptores de Cannabinoides/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Fibras de Estrés/metabolismo , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/genética , Proteína de Unión al GTP rhoA/metabolismo
7.
Dev Dyn ; 250(10): 1420-1431, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33760303

RESUMEN

BACKGROUND: Amphibians possess three kinds of dermal chromatophore: melanophores, iridophores, and xanthophores. Knockout Xenopus tropicalis that lack the pigmentation of melanophores and iridophores have been reported. The identification of the causal genes for xanthophore pigmentation or differentiation could lead to the creation of a see-through frog without three chromatophores. The genes causing xanthophore differentiation mutants are slc2a11b and slc2a15b in Japanese medaka (Oryzias latipes). RESULTS: To obtain a heritable line of X tropicalis mutants without yellow pigment, we generated slc2a7 and slc2a15a knockout animals because they have the greatest similarity to the O latipes slc2a11b and slc2a15b genes. The slc2a7 knockout frog had a bluish skin and there were no visible yellow pigments in stereo microscope and skin section observations. Furthermore, no pterinosomes, which are characteristic of xanthophores, were observed via transmission electron microscopy in the skin of knockout animals. CONCLUSIONS: We report the successful generation of a heritable no-yellow-pigment X tropicalis mutant after knock out of the slc2a7 gene. This finding will enable the creation of a see-through frog with no chromatophores.


Asunto(s)
Cromatóforos/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Melanóforos/metabolismo , Pigmentación/genética , Animales , Animales Modificados Genéticamente , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Xenopus
8.
Mol Reprod Dev ; 88(11): 744-757, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34618381

RESUMEN

Sperm matrix metalloproteinase-2 (MMP-2) is necessary for frog fertilization. Monospermy is ensured by a fast, electrical block to polyspermy mediated by a positive fertilization potential. To determine the role of the MMP-2 hemopexin domain (HPX) in a fast block to polyspermy during fertilization of the frog, Xenopus tropicalis, we prepared mutant frogs deficient in mmp2 gene using the transcription activator-like effector nuclease method. mmp2 ΔHPX (-/-) sperm without MMP-2 protein were able to fertilize wild-type (WT; +/+) eggs. However, polyspermy occurred in some eggs. The mutant sperm generated a normal fertilization potential amounting to 10 mV, and were able to fertilize eggs at 10 mV, at which WT sperm never fertilized. Sensitivity during voltage-dependent fertilization decreased in mutant sperm. This study demonstrates for the first time that the genetic alteration of the MMP-2 molecule in sperm causes polyspermy during fertilization of a monospermic species. Our findings provide reliable evidence that sperm MMP-2 is indispensable for the fast, electrical block to polyspermy during Xenopus fertilization.


Asunto(s)
Fertilización , Metaloproteinasa 2 de la Matriz , Animales , Masculino , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Potenciales de la Membrana , Óvulo , Interacciones Espermatozoide-Óvulo , Espermatozoides/metabolismo , Xenopus laevis
9.
Gen Comp Endocrinol ; 287: 113349, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31794731

RESUMEN

Anuran metamorphosis is perhaps the most dramatic developmental process regulated by thyroid hormone (TH). One of the unique processes that occur during metamorphosis is the complete resorption of the tail, including the notochord. Interestingly, recent gene knockout studies have shown that of the two known vertebrate TH receptors, TRα and TRß, TRß appears to be critical for notochord regression during tail resorption in Xenopus tropicalis. To determine the mechanisms underlying notochord regression, we carried out a comprehensive gene expression analysis in the notochord during metamorphosis by using RNA-Seq analyses of whole tail at stage 60 before any noticeable tail length reduction, whole tail at stage 63 when the tail length is reduced by about one half, and the rest of the tail at stage 63 after removing the notochord. This allowed us to identify many notochord-enriched, metamorphosis-induced genes at stage 63. Future studies on these genes should help to determine if they are regulated by TRß and play any roles in notochord regression.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Notocorda/crecimiento & desarrollo , RNA-Seq/métodos , Cola (estructura animal)/crecimiento & desarrollo , Xenopus laevis/crecimiento & desarrollo , Xenopus/genética , Animales
10.
Genes Cells ; 23(12): 998-1008, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30294949

RESUMEN

Thyroid hormones (THs) induce metamorphosis in amphibians, causing dynamic changes, whereas mammalian newborns undergo environmental transition from placenta to open air at birth. The similarity between amphibian metamorphosis and the mammalian perinatal periods has been repeatedly discussed. However, a corresponding developmental gene expression analysis has not yet been reported. In this study, we examined the developmental gene expression profiles in the brain and liver of Xenopus tropicalis during metamorphosis climax and compared them to the respective gene expression profiles of newborn rodents. Many upregulated genes identified in the tadpole brain during metamorphosis are also upregulated in the rodent brain during the first three postnatal weeks when the TH surge occurs. The upregulation of some genes in the brain was inhibited in thyroid hormone receptor α (TRα) knockout tadpoles but not in TRß-knockout tadpoles, implying that brain metamorphosis is mainly mediated by TRα. The expression of some genes was also increased in the liver during metamorphosis climax. Our data suggest that the rodent brain undergoes TH-dependent remodeling during the first three postnatal weeks as observed in X. tropicalis during the larva-to-adult metamorphosis.


Asunto(s)
Encéfalo/embriología , Encéfalo/metabolismo , Regulación del Desarrollo de la Expresión Génica , Hígado/embriología , Hígado/metabolismo , Metamorfosis Biológica/genética , Xenopus/embriología , Xenopus/genética , Albúminas/metabolismo , Animales , Perfilación de la Expresión Génica , Sinapsis/metabolismo , Urea/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo
11.
Gen Comp Endocrinol ; 277: 66-72, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30851299

RESUMEN

Tail resorption during anuran metamorphosis is perhaps the most dramatic tissue transformation that occurs during vertebrate development. Earlier studies in highly related anuran species Xenopus laevis and Xenopus tropicalis have shown that thyroid hormone (T3) receptor (TR) plays a necessary and sufficient role to mediate the causative effect of T3 on metamorphosis. Of the two known TR genes in vertebrates, TRα is highly expressed during both premetamorphosis and metamorphosis while TRß expression is low in premetamorphic tadpoles but highly upregulated as a direct target gene of T3 during metamorphosis, suggesting potentially different functions during metamorphosis. Indeed, gene knockout studies have shown that knocking out TRα and TRß has different effects on tadpole development. In particularly, homozygous TRß knockout tadpoles become tailed frogs well after sibling wild type ones complete metamorphosis. Most noticeably, in TRß-knockout tadpoles, an apparently normal notochord is present when the notochord in wild-type and TRα-knockout tadpoles disappears. Here, we have investigated how tail notochord resorption is regulated by TR. We show that TRß is selectively very highly expressed in the notochord compared to TRα. We have also discovered differential regulation of several matrix metalloproteinases (MMPs), which are known to be upregulated by T3 and implicated to play a role in tissue resorption by degrading the extracellular matrix (ECM). In particular, MMP9-TH and MMP13 are extremely highly expressed in the notochord compared to the rest of the tail. In situ hybridization analyses show that these MMPs are expressed in the outer sheath cells and/or the connective tissue sheath surrounding the notochord. Our findings suggest that high levels of TRß expression in the notochord specifically upregulate these MMPs, which in turn degrades the ECM, leading to the collapse of the notochord and its subsequent resorption during metamorphosis.


Asunto(s)
Metamorfosis Biológica , Notocorda/embriología , Receptores beta de Hormona Tiroidea/metabolismo , Xenopus/embriología , Xenopus/metabolismo , Animales , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Larva , Metaloproteinasas de la Matriz/genética , Metaloproteinasas de la Matriz/metabolismo , Metamorfosis Biológica/genética , Fenotipo , Cola (estructura animal) , Receptores alfa de Hormona Tiroidea/metabolismo
12.
BMC Pediatr ; 19(1): 39, 2019 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-30704433

RESUMEN

BACKGROUND: Finding an abdominal mass or hematuria is the initial step in diagnosing Wilms tumor. As the first manifestation of Wilms tumor, it is exceedingly rare for pulmonary tumor embolism to present with cardiac arrest. A case of a patient whose sudden cardiac arrest due to massive pulmonary tumor embolism of Wilms tumor was not responsive to resuscitation is presented. CASE PRESENTATION: The patient was a five-year-old girl who collapsed suddenly during activity in nursery school and went into cardiac arrest in the ambulance. Unfortunately, she was not responsive to conventional resuscitation. A judicial autopsy conducted at the local police department showed the main cause of her sudden cardiac arrest was attributed to multiple pulmonary tumor embolisms of stage IV Wilms tumor. CONCLUSIONS: Except for one reported case, treatments were not successful in all eight cardiac arrest cases with pulmonary tumor embolism of Wilms tumor. These results indicate that it is challenging not only to make an accurate diagnosis, but also to provide proper specific treatment in the cardiac arrest setting. We propose that flexible triage and prompt transfer to a tertiary hospital are necessary as an oncologic emergency to get such patients to bridging therapy combined with extracorporeal membrane oxygenation or immediate surgical intervention under cardiopulmonary bypass.


Asunto(s)
Paro Cardíaco/etiología , Neoplasias Renales/complicaciones , Embolia Pulmonar/complicaciones , Tumor de Wilms/complicaciones , Preescolar , Femenino , Humanos , Neoplasias Renales/diagnóstico , Tumor de Wilms/diagnóstico
13.
Dev Biol ; 426(2): 472-486, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27595926

RESUMEN

We describe a novel recessive and nonlethal pigmentation mutant in Xenopus tropicalis. The mutant phenotype can be initially observed in tadpoles after stage 39/40, when mutant embryos display markedly reduced pigmentation in the retina and the trunk. By tadpole stage 50 almost all pigmented melanophores have disappeared. Most interestingly, those embryos fail entirely to make pigmented iridophores. The combined reduction/absence of both pigmented iridophores and melanophores renders these embryos virtually transparent, permitting one to easily observe both the developing internal organs and nervous system; accordingly, we named this mutant no privacy (nop). We identified the causative genetic lesion as occurring in the Xenopus homolog of the human Hermansky-Pudlak Syndrome 6 (HPS6) gene, combining several approaches that utilized conventional gene mapping and classical and modern genetic tools available in Xenopus (gynogenesis, BAC transgenesis and TALEN-mediated mutagenesis). The nop allele contains a 10-base deletion that results in truncation of the Hps6 protein. In humans, HPS6 is one of the genes responsible for the congenital disease HPS, pathological symptoms of which include oculocutaneous albinism caused by defects in lysosome-related organelles required for pigment formation. Markers for melanin-producing neural crest cells show that the cells that would give rise to melanocytes are present in nop, though unpigmented. Abnormalities develop at tadpole stages in the pigmented retina when overall pigmentation becomes reduced and large multi-melanosomes are first formed. Ear development is also affected in nop embryos when both zygotic and maternal hsp6 is mutated: otoliths are often reduced or abnormal in morphology, as seen in some mouse HPS mutations, but to our knowledge not described in the BLOC-2 subset of HPS mutations nor described in non-mammalian systems previously. The transparency of the nop line suggests that these animals will aid studies of early organogenesis during tadpole stages. In addition, because of advantages of the Xenopus system for assessing gene expression, cell biological mechanisms, and the ontogeny of melanosome and otolith formation, this should be a highly useful model for studying the molecular mechanisms underlying the acquisition of the HPS phenotype and the underlying biology of lysosome-related organelle function.


Asunto(s)
Modelos Animales de Enfermedad , Síndrome de Hermanski-Pudlak , Mutación , Proteínas de Xenopus/genética , Xenopus/genética , Albinismo/genética , Animales , Cromosomas Artificiales Bacterianos , Oído Interno/anomalías , Femenino , Humanos , Larva/metabolismo , Melaninas/biosíntesis , Melanosomas/fisiología , Mutagénesis Sitio-Dirigida , Organogénesis , Membrana Otolítica/anomalías , Fenotipo , Pigmentación/genética , Eliminación de Secuencia , Xenopus/embriología , Proteínas de Xenopus/deficiencia , Proteínas de Xenopus/fisiología
15.
Genes Cells ; 21(3): 275-86, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26847415

RESUMEN

Tail regression is one of the most prominent transformations observed during anuran metamorphosis. A tadpole tail that is twice as long as the tadpole trunk nearly disappears within 3 days in Xenopus tropicalis. Several years ago, it was proposed that this phenomenon is driven by an immunological rejection of larval-skin-specific antigens, Ouro proteins. We generated ouro-knockout tadpoles using the TALEN method to reexamine this immunological rejection model. Both the ouro1- and ouro2-knockout tadpoles expressed a very low level of mRNA transcribed from a targeted ouro gene, an undetectable level of Ouro protein encoded by a target gene and a scarcely detectable level of the other Ouro protein from the untargeted ouro gene in tail skin. Furthermore, congenital athymic frogs were produced by Foxn1 gene modification. Flow cytometry analysis showed that mutant frogs lacked splenic CD8(+) T cells, which play a major role in cytotoxic reaction. Furthermore, T-cell-dependent skin allograft rejection was dramatically impaired in mutant frogs. None of the knockout tadpoles showed any significant delay in the process of tail shortening during the climax of metamorphosis, which shows that Ouro proteins are not essential to tail regression at least in Xenopus tropicalis and argues against the immunological rejection model.


Asunto(s)
Queratinas/metabolismo , Metamorfosis Biológica/genética , Proteínas de Xenopus/metabolismo , Animales , Linfocitos T CD8-positivos/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Regulación del Desarrollo de la Expresión Génica , Queratinas/genética , Timo/citología , Timo/metabolismo , Xenopus , Proteínas de Xenopus/genética
16.
Zoolog Sci ; 34(5): 414-418, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28990472

RESUMEN

Tail regression in amphibian tadpoles during metamorphosis is one of the most dynamic morphological changes in animal development and is induced by thyroid hormone (TH). It has been proposed that tail resorption is driven by immunological rejection in Xenopus laevis, based on experimental evidence showing that larval skin grafts become atrophic on syngenic recipient adult frogs. This led to the hypothesis that tail regression is induced by an immunological rejection against larval skin-specific antigens called Ouro proteins. However, our group has demonstrated that ouro-knockout tadpoles undergo normal metamorphosis, including tail resorption in Xenopus tropicalis, which indicates that the expression of ouro genes is not necessary for tail regression. In the present study, we showed that an inhibitor of TH synthesis promotes the survival of larval tail skin grafts on syngenic adult Xenopus tropicalis frogs. The levels of endogenous THs in adult frogs were also comparable to those in metamorphosing tadpoles of Xenopus laevis with a regressing tail, and TH induced the regression of tadpole tail tips of Xenopus tropicalis in organ culture. Taken together, these results strongly suggest that endogenous THs in the recipient adult frog induce the degeneration of syngenic tail skin grafts.


Asunto(s)
Trasplante de Piel , Hormonas Tiroideas/biosíntesis , Xenopus/fisiología , Animales , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Larva , Metamorfosis Biológica , Piel/inmunología , Piel/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo
17.
Dev Biol ; 408(2): 328-44, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25724657

RESUMEN

Mutations in the Pax6 gene cause ocular defects in both vertebrate and invertebrate animal species, and the disease aniridia in humans. Despite extensive experimentation on this gene in multiple species, including humans, we still do not understand the earliest effects on development mediated by this gene. This prompted us to develop pax6 mutant lines in Xenopus tropicalis taking advantage of the utility of the Xenopus system for examining early development and in addition to establish a model for studying the human disease aniridia in an accessible lower vertebrate. We have generated mutants in pax6 by using Transcription Activator-Like Effector Nuclease (TALEN) constructs for gene editing in X. tropicalis. Embryos with putative null mutations show severe eye abnormalities and changes in brain development, as assessed by changes in morphology and gene expression. One gene that we found is downregulated very early in development in these pax6 mutants is myc, a gene involved in pluripotency and progenitor cell maintenance and likely a mediator of some key pax6 functions in the embryo. Changes in gene expression in the developing brain and pancreas reflect other important functions of pax6 during development. In mutations with partial loss of pax6 function eye development is initially relatively normal but froglets show an underdeveloped iris, similar to the classic phenotype (aniridia) seen in human patients with PAX6 mutations. Other eye abnormalities observed in these froglets, including cataracts and corneal defects, are also common in human aniridia. The frog model thus allows us to examine the earliest deficits in eye formation as a result of pax6 lesions, and provides a useful model for understanding the developmental basis for the aniridia phenotype seen in humans.


Asunto(s)
Aniridia/embriología , Aniridia/genética , Proteínas del Ojo/genética , Proteínas del Ojo/fisiología , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/fisiología , Mutación , Factores de Transcripción Paired Box/genética , Factores de Transcripción Paired Box/fisiología , Proteínas Represoras/genética , Proteínas Represoras/fisiología , Xenopus/embriología , Xenopus/genética , Animales , Aniridia/patología , Secuencia de Bases , Codón sin Sentido , ADN/genética , Modelos Animales de Enfermedad , Exones , Ojo/embriología , Ojo/crecimiento & desarrollo , Marcación de Gen , Humanos , Datos de Secuencia Molecular , Mutagénesis , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/deficiencia , Fenotipo , Proteínas Represoras/deficiencia , Especificidad de la Especie
18.
Zoolog Sci ; 33(3): 290-4, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27268983

RESUMEN

Albino animals are useful for in situ hybridization experiments that demonstrate gene expression in embryos and organs, for the immunological rejection of skin grafts transplanted to host animals, and to identify tissues with regenerative ability during limbs and retina regeneration processes. Cynops pyrrhogaster has extensive regenerating capacities. To facilitate regenerative research, in the present study, we produced albino C. pyrrhogaster using genomic editing. The DNA fragment containing part of the tyrosinase gene from C. pyrrhogaster was amplified using degenerate primers corresponding to evolutionarily conserved nucleotide sequences among several species, and the nucleotide sequence was determined. We designed a transcription activator-like effector nuclease (TALEN) that targets a candidate of the C. pyrrhogaster tyrosinase gene. Fertilized eggs were injected with TALEN mRNA, and albinos of C. pyrrhogaster were obtained. The results of the present study demonstrated that TALEN can be used effectively for genomic editing in C. pyrrhogaster and that the candidates of the tyrosinase gene that were cloned by us are essential for melanin synthesis. The albino newts created in the present study can be used as versatile experimental material.


Asunto(s)
Regulación de la Expresión Génica/genética , Melaninas/genética , Monofenol Monooxigenasa/genética , Salamandridae/genética , Animales , Secuencia de Bases , Análisis Mutacional de ADN , Edición Génica , Monofenol Monooxigenasa/química , Alineación de Secuencia , Nucleasas de los Efectores Tipo Activadores de la Transcripción/metabolismo , Cigoto/fisiología
19.
Endocr J ; 63(11): 983-990, 2016 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-27545660

RESUMEN

21-hydroxylase deficiency (21-OHD) is the most common type of congenital adrenal hyperplasia. In addition to the clinical problems caused by adrenal insufficiency and androgen excess, a risk for obesity and metabolic syndrome during young adulthood is a major ramification of the disease. Although glucocorticoid therapy is very likely to be one of the contributory factors, the precise causes of the metabolic status of adult 21-OHD patients remain to be clarified. Previously we reported that 21-OHD patients developed early onset AR, a condition which might create a risk for obesity and metabolic syndrome in adulthood. In order to elucidate the association between the onset of AR and factors during the fetal period to early infancy, we conducted a retrospective longitudinal analysis of 29 21-OHD patients (male: 14 cases, female: 15 cases, salt wasting type: 16, simple virilizing type: 13), who were identified by newborn screening and followed up at least until the age 10 years. Body size at birth, lower body weight, and lower BMI were found to precipitate the timing of AR. On the other hand, no significant association was observed between the timing of AR and sex, gestational age, treatment regimen (including cumulative dose of HDC), and disease severity (the type of the disease, the value of DHEA-S and 17-OHP). There are two points to consider: first, in 21-OHD patients treated with glucocorticoid substitution therapy, the risk for early AR cannot be reduced by adjusting the dose of glucocorticoid; second, fetal factors might affect the metabolic status of 21-OHD patients.


Asunto(s)
Adiposidad , Hiperplasia Suprarrenal Congénita , Peso al Nacer/fisiología , Índice de Masa Corporal , Recién Nacido de Bajo Peso/crecimiento & desarrollo , Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/metabolismo , Desarrollo Infantil/fisiología , Preescolar , Femenino , Humanos , Recién Nacido , Estudios Longitudinales , Masculino , Obesidad Infantil/etiología , Obesidad Infantil/metabolismo , Estudios Retrospectivos
20.
Epilepsy Behav ; 52(Pt A): 180-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26439655

RESUMEN

OBJECTIVE: Since benzodiazepines (BZPs) became clinically available for the treatment of status epilepticus (SE) in children, the incidence of neurological sequelae has increased. However, the cause-effect relationship is poorly understood. In this paper, we examined the effect of BZPs on an inflammation-induced SE (iSE) animal model. METHOD: Inflammation was induced by injecting poly(I:C) (pIC 10 mg/kg, postnatal day 12-14), seizure was induced by injecting pilocarpine hydrochloride (PILO 200 mg/kg, postnatal day 15) into C57BL/6J mice, and the pIC+PILO mice were used as the iSE model (miSE). The GABA-A receptor agonist midazolam (MDL 0.5 mg/kg) was used to inhibit seizures. Sequelae were evaluated by performing behavior and immunohistochemical analyses in the chronic phase. RESULT: The exploratory activity of mice in the miSE plus MDL group increased significantly, indicating that hyperactivity was newly induced by MDL in miSE mice. The contextual fear memory of the miSE mice was also significantly increased and that of miSE treated with MDL returned to the normal level. The parvalbumin-positive GABA neurons were decreased in number by pIC+PILO which was rescued by MDL. Apoptosis marker ssDNA-positive cells were increased by pIC+PILO which could not be rescued by MDL. Therefore, we propose that BZP-dependent therapy for SE needs to be rethought from the perspective of using other treatment approaches.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Benzodiazepinas/uso terapéutico , Inflamación/complicaciones , Estado Epiléptico/tratamiento farmacológico , Estado Epiléptico/etiología , Animales , Apoptosis/efectos de los fármacos , Convulsivantes , Conducta Exploratoria/efectos de los fármacos , Agonistas del GABA/farmacología , Inflamación/inducido químicamente , Inflamación/psicología , Masculino , Ratones , Ratones Endogámicos C57BL , Midazolam/farmacología , Neuronas/efectos de los fármacos , Parvalbúminas , Pilocarpina , Poli I-C , Receptores de GABA-A/efectos de los fármacos , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico , Convulsiones/psicología , Estado Epiléptico/psicología
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