• Title/Summary/Keyword: Lethal mutations

Search Result 37, Processing Time 0.027 seconds

Defective Self-Renewal and Differentiation of GBA-Deficient Neural Stem Cells Can Be Restored By Macrophage Colony-Stimulating Factor

  • Lee, Hyun;Bae, Jae-sung;Jin, Hee Kyung
    • Molecules and Cells
    • /
    • v.38 no.9
    • /
    • pp.806-813
    • /
    • 2015
  • Gaucher disease (GD) is an autosomal recessive lysosomal storage disorder caused by mutations in the glucocerebrosidase gene (GBA), which encodes the lysosomal enzyme glucosylceramidase (GCase). Deficiency in GCase leads to characteristic visceral pathology and lethal neurological manifestations in some patients. Investigations into neurogenesis have suggested that neurodegenerative disorders, such as GD, could be overcome or at least ameliorated by the generation of new neurons. Bone marrowderived mesenchymal stem cells (BM-MSCs) are potential candidates for use in the treatment of neurodegenerative disorders because of their ability to promote neurogenesis. Our objective was to examine the mechanism of neurogenesis by BM-MSCs in GD. We found that neural stem cells (NSCs) derived from a neuronopathic GD model exhibited decreased ability for self-renewal and neuronal differentiation. Co-culture of GBA-deficient NSCs with BM-MSCs resulted in an enhanced capacity for self-renewal, and an increased ability for differentiation into neurons or oligodendrocytes. Enhanced proliferation and neuronal differentiation of GBA-deficient NSCs was associated with elevated release of macrophage colony-stimulating factor (M-CSF) from BM-MSCs. Our findings suggest that soluble M-CSF derived from BM-MSCs can modulate GBA-deficient NSCs, resulting in their improved proliferation and neuronal differentiation.

A Korean Girl with Campomelic Dysplasia caused by a Novel Nonsense Mutation within the SOX9 Gene

  • Ko, Jung Min;Hah, J.-Hun;Kim, Suk-Wha;Cho, Tae-Joon;Kim, Gu-Hwan;Yoo, Han-Wook
    • Journal of Genetic Medicine
    • /
    • v.9 no.2
    • /
    • pp.89-92
    • /
    • 2012
  • Campomelic dysplasia (CMD) is a rare, often lethal, genetic disorder characterized by multiple congenital anomalies and abnormal development of the reproductive organs in males. Mutations in the SOX9 gene are known to cause CMD. We present a Korean CMD girl with a normal 46,XX karyotype and a female reproductive organ phenotype. She was born at 2.35 kg at 38 weeks of gestation and showed characteristic phenotypes, including cleft palate, micrognathia, hypertelorism, flat nasal bridge, congenital bowing of limbs, hypoplastic scapulae, deformed pelvis, and 11 pairs of ribs. She also had an atrioseptal defect of the heart and marked laryngotracheomalacia requiring tracheostomy and tracheopexy. SOX9 mutation analysis revealed the presence of a novel nonsense mutation, $p.Gln369^*$, and the patient was genetically confirmed to have CMD. Although she showed marked failure to thrive and neurodevelopmental delay, she is now 40 months of age and is the only surviving patient with CMD in Korea.

Imidazole Ring-Opened DNA Purines and Their Biological Significance

  • Barbara, Tudek
    • BMB Reports
    • /
    • v.36 no.1
    • /
    • pp.12-19
    • /
    • 2003
  • Fragmentation of purine imidazole ring and production of formamidopyrimidines in deoxynucleosides (Fapy lesions) occurs upon DNA oxidation as well as upon spontaneous or alkali-triggered rearrangement of certain alkylated bases. Many chemotherapeutic agents such as cyclophosphamide or thiotepa produce such lesions in DNA. Unsubstituted FapyA and FapyG, formed upon DNA oxidation cause moderate inhibition of DNA synthesis, which is DNA polymerase and sequence dependent. Fapy-7MeG, a methylated counterpart of FapyG-, a efficiently inhibits DNA replication in vitro and in E.coli, however its mutagenic potency is low. This is probably due to preferential incorporation of cytosine opposite Fapy-7MeG and preferential extension of Fapy-7MeG:C pair. In contrast, FapyA and Fapy-7MeA possess miscoding potential. Both lesions in SOS induced E.coli preferentially mispair with cytosine giving rise to A$\rightarrow$G transitions. Fapy lesions substituted with longer chain alkyl groups also show simult aneous lethal and mutagenic properties. Fapy lesions are actively eliminated from DNA by repair glycosylases specific for oxidized purines and pyrimidines both in bacteria and eukaryotic cells. Bacterial enzymes include E.coli formamidopyrimidine-DNA-glycosylase (Fpg protein), endonuclease III (Nth protein) and endonuclease VIII (Nei protein).

Nuclear DNA Quantification of Some Ceramialean Algal Spermatia by Fluorescence Microscopic Image Processing and their Nuclear SSU rDNA Sequences

  • Choi, Han-Gu;Lee, Eun-Young;Oh, Yoon-Sik;Kim, Hyung-Seop;Lee, In-Kyu
    • ALGAE
    • /
    • v.19 no.2
    • /
    • pp.79-90
    • /
    • 2004
  • Nuclear DNA contents of spermatia from eight ceramiacean and four dasyacean algae (Ceramiales, Rhodophyta) and microspores from two land plants were estimated by fluorescence microscopic image processing and their nuclear SSU rDNA sequence data were analyzed. In frequency distribution patterns, the DAPI-stained nuclear volume (NV) of spermatia showed two peaks corresponding to 1C and 2C. Nuclear 2C DNA contents estimated from NV were 0.45-2.31 pg in ceramiacean and 0.40-0.57 pg in dasyacean algae and 8.42-9.51 pg in two land plants, Capsicum annuum and Nicotiana tabacum. By nuclear patterning of vegetative cells derived from an apical cell, 2C DNA contents of spermatia were 2.31 pg in an alga having uninucleate and non-polyploid nucleus (Aglaothamnion callophyllidicola), 0.45-1.94 pg in algae having uninucleate and polyploid nucleus (Antithamnion spp. and Pterothamnion yezoense), and 0.40-0.62 pg in algae having multinucleate and non-polyploid nuclei (Griffithsia japonica and dasyacean algae). Each mature spermatium and microspore (pollen grain) seemed to have a 2C nucleus, which may provide a genetic buffering system to protect the genetic content of a spermatium and microspore from potentially lethal mutations. Nuclear DNA content and SSU rDNA sequence of Antithamnion sparsum from Korea were reasonably different from those of Antithamnion densum from France. The data did not support the previous taxonomic studies that these two taxa could be conspecific.

An early transcription checkpoint ; A dual role of capping enzyme in RNA polymerase II transcription

  • Cho Eun-Jung
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 2005.04a
    • /
    • pp.5-14
    • /
    • 2005
  • Recently, data from several groups have raised the concept of 'checkpoint' in transcription. As capping of nascent RNA transcript is tightly coupled to RNA polymerase II transcription, we seek to obtain direct evidence that transcripiton checkpoint via capping enzyme functions in this early regulatory step. One of temperature sensitive (ts) alleles of ceg1, a guanylyltransferase subunit of the Saccharomyces cerevisiaecapping enzyme, showed 6-azauracil (6AU) sensitivity at the permissive growth temperature, which is a phenotype that is correlated with a transcription elongational defect. This ts allele, ceg1-63 also has an impaired ability to induce PUR5 in response to a 6AU treatment. However, this cellular and molecular defect is not due to the preferential degradation of the transcript attributed from a lack of guanylyltransferase activity. On the contrary, the data suggests that the guanylyltransferase subunit of the capping enzyme plays a role in transcription elongation. First, in addition to the 6AU sensitivity, ceg1-63is synthetically lethal with elongation defective mutations of the largest subunit of RNA polymerase II. Secondly, it exhibited a lower GAL1 mRNA turn-over after glucoseshut off. Third, it decreased the transcription read through a tandem array of promoter proximal pause sites in an orientation dependent manner. Interestingly, this mutant also showed lower pass through a pause site located further downstream of the promoter. Taken together, these results suggest that the capping enzyme plays the role of an early transcription checkpoint possibly in the step of the reversion of repression by stimulating polymerase to escape from the promoter proximal arrest once RNA becomes appropriately capped.

  • PDF

Identification of a novel frameshift mutation (L345Sfs*15) in a Korean neonate with methylmalonic acidemia

  • Kim, Young A;Kim, Ji-Yong;Kim, Yoo-Mi;Cheon, Chong Kun
    • Journal of Genetic Medicine
    • /
    • v.14 no.2
    • /
    • pp.80-85
    • /
    • 2017
  • Methylmalonic acidemia (MMA) is an autosomal recessive metabolic disorder characterized by an abnormal accumulation of methylmalonyl-CoA and methylmalonate in body fluids without hyperhomocysteinemia. Cardiac disease is a rarely known lethal complication of MMA, herein, we report a Korean neonate diagnosed with MMA on the basis of biochemical and genetic findings, who developed cardiomyopathy, resulting in sudden death. The patient presented vomiting and lethargy at 3 days of age. Initially, the patient had an increased plasma propionylcarnitine/acetylcarnitine concentration ratio of 0.49 in a tandem mass spectrometry analysis and an elevated ammonia level of $537{\mu}mol/L$. Urine organic acid analysis showed increased excretion of methylmalonate. Subsequent sequence analysis of the methylmalonyl-CoA mutase (MUT) gene revealed compound heterozygous mutations c.323G>A (p.Arg108His) in exon 1 and c.1033_1034del (p. Leu345Serfs*15) in exon 4, the latter being a novel mutation. In summary, this is the first case of MMA and cardiomyopathy in Korea that was confirmed by genetic analysis to involve a novel MUT mutation.

A Case with Perinatal Hypophosphatasia Caused by the ALPL Mutations (ALPL 유전자의 돌연변이를 가진 양성 주산기 저인산증 1례)

  • Kim, Joonil;Kang, Eungu;Kim, Yoon-Myung;Lee, Beom Hee;Kim, Gu-Hwan;Yoo, Han-Wook
    • Journal of The Korean Society of Inherited Metabolic disease
    • /
    • v.16 no.3
    • /
    • pp.141-147
    • /
    • 2016
  • Hypophosphatasia is caused by the mutations in ALPL, which encodes tissue-nonspecific alkaline phosphatase (TNSALP). It can be inherited either in an autosomal dominant or recessive manner. Clinically, hypophophosphatasia is characterized by skeletal findings similar to those in rickets or osteomalacia, but serum alkaline phosphatase levels are decreased in the affected patients. Hypophosphatasia can be classified into six clinical forms according to age at diagnosis and severity of symptoms: perinatal lethal, infantile, childhood, adult, odontohypophosphatasia, and perinatal benign. As being a very rare disease, only one case has been reported in Korean population. Here we describe a case with perinatal benign hypophosphatasia with recessive ALPL mutations. Bowing of lower legs was detected in prenatal period and low serum alkaline phosphatase level was noted after birth. During the follow-up evaluation for 4.5 years, bone mineralization and legs bowing were improved but the growth retardation was persistent. As the recombinant bone-targeted human TNSALP became available, the clinical improvement of the affected patients is expected including the case described here with this treatment. More efforts are needed to identify the cases affected by hypophosphatasia.

  • PDF

Studies on the Biological Effects of Chemosterilant, Hempa, on the Rice Weevil (Sitophilus oryzae 1.) and Transmission of Sterility (화학적 불임유기물질 Hempa가 쌀바구미(Sitophilus oryzae L.)에 미치는 생물학적 영향 및 불임성의 전달에 관한 연구)

  • Shim Jai Wook
    • Korean journal of applied entomology
    • /
    • v.12 no.1
    • /
    • pp.1-21
    • /
    • 1973
  • Some experiments were conducted to investigate the effects of the chemosterilant, hempa, on the biology of the rice weevil, Sitophilus oryzae L., and the transmission of the lethal factors in the progeny. One to three days old adult males were fed on the wheat grains treated with concentrations of 0.0625, 0.125, 0.25, and $0.5\%$ of hempa water solution. The effects of the treatment on the mortality, longevity, and the performance of oviposition were examined for the Pl generation, and the hatchability and mortality in the postembryonic development were also tested in the $F_1,\;F_2,\;BC_1,\;F_3,\;and\;BC_2$ generations to analyze the inheritance of the lethal factors. The results obtained were summarized as follows. (1) The average longevity of the treated males were ranged from 26.6 to 30.4 days, and indicated no statistical differences. (2) The mortality of the treated males were ranged between $3.3\%\;and\;13.3\%$ and showed no statistical significance. (3) The overall mean number of eggs laid by a female mated to a treated male with concentrations of 0.0625, 0.125, 0.26 and $0.5\%$ were 3.78, 4.05, 3.75 and 3.61 for the respective treatments, and they were not differ significantly from those of control which were 3.60 per female per 3 day period. The unmated female laid 1.91 in the same period, and significantly differ from those in other experimental groups. (4) The overall mean hatchability of the eggs laid by the females mated with males that had been treated with various concentrations of hempa were 86.82, 64.77, 53.47, 40.33 and $24.78\%$ for the respective concentrations of 0, 0.0625, 0.125, 0.25 and $0.5\%$. The hatchability decreased with the increasing concentrations. (5) The minimum hatchabilities were obtained from the eggs laid in the period of 10-12 days after treatment, then the hatchability increased showing some recovery. The recovery seemed to be very much delayed for the males which had been treated with the greater concentrations. Such a difference in hatchability might be related with the sensitivity of the developmental stages of the sperms, and broader spectrum in the stages and severer effects seemed to be associated with the increased concentrations. (6) The overall mean of larval mortality in the $F_l$ generation were 6.55, 17.89, 27.40, 35.42 and $52.17\%$ for the respective concentrations of 0,0.0625, 0.125,0.25 and $0.5\%$. And there was a tendency to increase in the mortality with the increase of concentrations. (7) The correlation coefficients between per cent sterile eggs and larval mortality for the experimental plots of 0.125, 0.25 and $0.5\%$ treatments showed r=+0.83 and +0.85, respectively, and it seemed to be close correlation between the lethal effects on the embryonic and post-embryonic developments. (8) Since the $SC_{50}$ of the sterile eggs was $0.133\%$ and $SC_{50}$ of the larval mortality was $0.565\%$, it was considered that tile lethal factors expressed more in the egg stages than the larval stages. (9) The ratio of female to male in the $F_l$ adults showed 100 : 125, 100 : 108 and 100 : 124 for the plots of 0.125, 0.25 and $0.5\%$ treatments, respectively. And it n·as considered that the sex ratio distortions might occur with the higher concentrations. (10) When the F, males originated 1.on the eggs had been laid by p, in the period of 16-18 days after treatment, were crossed to normal females $(BC_1)$ and made sib matings $(F_2)$, the per cent sterile eggs of the $BC_1$ generation were 13.88 and $33.04\%$ , and were 31.01 and $38.73\%$ for the $F_2$generation with the plots of 0.0625 and $0.125\%$ treatment, respectively. And these seemed to be a results of the $F_1$ individuals are carrying some chromosomal aberrations (11) The larval mortality was the highest in the $F_2$ plot and followed the female backcross plot, and the least in the male backcrosses. (12) The proportions of 1st and 2nd instar larvae among the larval development at tile 17th day after oviposition were 10.98, 27.26, 32.98 and $15.73\%$ in the normal female $\times$ normal male, $F_1$ female$\times$normal male, normal $female \;\times F_1$ male and $female \;\times F_1$ male plots, respectively. It was considered that the larval development might be delayed by the treatment in the 2nd generation. (13) Per cent larval mortality and sterile eggs were greater in the $F_2$ sib mating plots $(F_3)$ than both of $F_2$ backcrosses. Therefore, it seemed that some of the recessive lethal mutations might affect in the further generations. (14) The sterility, induced by the treatment of chemosterilant, hempa, was considered as the result of the dominant lethal mutations due to chromosomal aberrations such as translocation and/or deletion. The effects of these lethal factors seemed to be inherited tip to 3rd generation after treatment.

  • PDF

The Complex Surgical Management of the First Case of Severe Combined Immunodeficiency and Multiple Intestinal Atresias Surviving after the Fourth Year of Life

  • Guana, Riccardo;Garofano, Salvatore;Teruzzi, Elisabetta;Vinardi, Simona;Carbonaro, Giulia;Cerrina, Alessia;Morra, Isabella;Montin, Davide;Mussa, Alessandro;Schleef, Jurgen
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.17 no.4
    • /
    • pp.257-262
    • /
    • 2014
  • Severe combined immunodeficiency (SCID) is a life-threatening syndrome of recurrent infections and gastro-intestinal alterations due to severe compromise of T cells and B cells. Clinically, most patients present symptoms before the age of 3 months and without intervention SCID usually results in severe infections and death by the age of 2 years. Its association with intestinal anomalies as multiple intestinal atresias (MIA) is rare and worsens the prognosis, resulting lethal. We describe the case of a four year-old boy with SCID-MIA. He presented at birth with meconium peritonitis, multiple ileal atresias and underwent several intestinal resections. A targeted Sanger sequencing revealed a homozygous 4-bp deletion ($c.313{\Delta}TATC$; p.Y105fs) in tetratricopeptide repeat domain 7A (TTC7A). He experienced surgical procedures including resection and stricturoplasty. Despite parenteral nutrition-associated liver disease, the patient is surviving at the time of writing the report. Precocious immune system assessment, scrutiny of TTC7A mutations and prompt surgical procedures are crucial in the management.

A Case of Smith-Lemli-Opitz Syndrome in DHCR7 Mutation (DHCR 7 유전자 돌연변이로 확진된 스미스-렘리-오피츠 증후군 1례)

  • Jeong, Yu Ju;Huh, Rimm;Kwun, Younghee;Lee, Jieun;Cho, Sung Yoon;Ki, Chang-Seok;Jin, Dong-Kyu
    • Journal of The Korean Society of Inherited Metabolic disease
    • /
    • v.14 no.1
    • /
    • pp.60-65
    • /
    • 2014
  • Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disease caused by a defect in cholesterol biosynthesis. This mutation encodes 7-dehydrocholesterol reductase (DHCR7), which is located on chromosome 11q13. It is characterized by typical facial appearances, microcephaly, small up-turned nose, cleft palate, syndactyly, and is correlated with cardiac, gastrointestinal and genital malformations. There may also be mental retardation, behavioral problems and growth retardation. It causes a broad spectrum of effects, ranging from a mild disorder of learning and behavior to a lethal malformation. There are four reports of Smith-Lemli-Opitz syndrome in Korean children. Here, we describe a two months old female with microcephaly, toe syndactyly and a cleft soft palate who was diagnosed as SLOS with c. 1054 C>T (p.R352W) and c.907G>A (p. G303R) mutations.