Partial dislocation emission from grain boundaries in metals with medium-to-high stacking fault ... more Partial dislocation emission from grain boundaries in metals with medium-to-high stacking fault energies is observed primarily in the grain size range of a few tens of nanometers. Here we report that a reduction in the stacking fault energy permits the emission of partial dislocations from grain boundaries in ultrafine-grained materials with grain sizes significantly larger than 100 nm and this produces twinning. Such twins are effective in increasing the dislocation storage capacity, which may be used to improve the ductility.
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban
This paper studied the effects of probiotics on the sediment of Penaeus vannamei pond during 117 ... more This paper studied the effects of probiotics on the sediment of Penaeus vannamei pond during 117 days of culture period. The results showed that probiotics application significantly decreased the concentrations of total nitrogen, total phosphorous, and sulfide in sediment, but no significant difference was observed in total plate count (TPC) of microbes between treated and control ponds. The final average presumptive vibrio count (PVC) of treated pond sediment (3.65 x 10(3) cfu x g(-1)) was significantly lower than that of the control (1.16 x 10(5) cfu x g(-1)), while the average number of BS (Bacillus), AB (ammonifying bacteria), PSOB (presumptive sulphur oxidizing bacteria) and SRB (sulphur reducing bacteria) in treated pond sediment was higher than that of the control. These data showed that probiotics could decrease the nutrients (nitrogen, phosphate and sulfur) accumulation and improve the composition of bacterial populations in pond sediment, and thus, supply a good sediment e...
ABSTRACT Effect of viable Bacillus coagulans as a dietary probiotic on the growth performance, su... more ABSTRACT Effect of viable Bacillus coagulans as a dietary probiotic on the growth performance, survivorship, immune response, and meat quality of the common carp, Cyprinus carpio, was investigated. Three treatments (T-1, T-2, and T-3) and a control, each with three replicates, were established. T-1, T-2, and T-3 groups were fed with diets containing different levels of probiotic (1 × 107 cfu/g, 2 × 107 cfu/g, and 4 × 107 cfu/g, respectively). After 45 d, the fish fed with probiotic had significantly higher (P < 0.05) daily weight gain compared to that of the control group. Significant increases (P < 0.05) in final weight, relative weight gain rate, lysozyme, myeloperoxidase, and respiratory burst activities were obtained in the T-2 and T-3 compared with those of the control. Fish in the control group showed the lowest (P < 0.05) content of complement component 3. Significantly (P < 0.05) improved contents of crude fat, inosine, and inosinic acid were observed in the T-2 and T-3. Our results indicated that the use of B. coagulans as a dietary probiotic for the common carp could improve growth performance, meat quality, and induce a positive modulation on immune response.
Determination of the elastic modulus of nanostructures with sizes at several nm range is challeng... more Determination of the elastic modulus of nanostructures with sizes at several nm range is challenge. In this study, we designed an experiment to measure the elastic modulus of amorphous Al2O3 films with thicknesses varying between 2 and 25 nm. The amorphous Al2O3 was in the form of a shell, wrapped around GaAs nanowires, thereby forming an effective core/shell structure. The GaAs cores comprised a single crystal structure with a diameter of 100 nm. Combined in-situ compression transmission electron microscopy and finite element analysis (FEA) were used to evaluate the elastic modulus of the overall core/shell nanowires. A core/shell model was applied to de-convolute the elastic modulus of the Al2O3 shell from the core. The results indicate that the elastic modulus of amorphous Al2O3 increases significantly when the thickness of the layer is smaller than 5 nm. This novel nanoscale materials can be attributed to the re-construction of bonding at the surface of the material, coupled wit...
Droplet epitaxy is an important method to produce epitaxial semiconductor quantum dots (QDs). Dro... more Droplet epitaxy is an important method to produce epitaxial semiconductor quantum dots (QDs). Droplet epitaxy of III-V QDs comprises group III elemental droplet deposition and the droplet crystallization through the introduction of group V elements. Here, we report that, in the droplet epitaxy of InAs/GaAs(001) QDs using metal-organic chemical vapor deposition, significant elemental diffusion from the substrate to In droplets occurs, resulting in the formation of In(Ga)As crystals, before As flux is provided. The supply of As flux suppresses the further elemental diffusion from the substrate and promotes surface migration, leading to large island formation with a low island density.
Glass transition temperature and plastic yield strength are known to be correlated in metallic gl... more Glass transition temperature and plastic yield strength are known to be correlated in metallic glasses. We have observed by in situ synchrotron high energy X-ray diffraction anisotropy of the thermal expansion behavior in the nearest neighbor and second nearest neighbor atomic distances in the building blocks of ZrCuNiAl based bulk metallic glass, leading inevitably to shear. Mechanical yielding of the latter on the atomic scale leads to the glass transition and the increase of the free volume. These experimental results uncover the mechanism, how glass transition and yield strength are linked.
Transactions on Machine Learning and Data Mining, 2008
Classification Association Rule Mining (CARM) is an approach to classifier generation that builds... more Classification Association Rule Mining (CARM) is an approach to classifier generation that builds an Association Rule Mining based classifier using Classification Association Rules (CARs). Regardless of which particular CARM algorithm is used, a similar set of CARs is always generated from data, and a classifier is usually presented as an ordered list of CARs, based on a selected rule ordering
During germ cell development, epigenetic modifications undergo extensive remodeling. Abnormal epi... more During germ cell development, epigenetic modifications undergo extensive remodeling. Abnormal epigenetic modifications usually result in germ cell loss and reproductive defect. Prmt5 (Protein arginine methyltransferase 5) encodes a protein arginine methyltransferase which has been demonstrated to play important roles in germ cell development during embryonic stages. In the present study, we found that Prmt5 was also abundantly expressed in male germ cells after birth. Inactivation of this gene by crossing with Stra8-Cre transgenic mice resulted in germ cell loss during spermatogenesis. Further study revealed that the germ cell development was grossly normal before P10. However, most of the germ cells in Prmt5(Δ/f); Stra8-Cre mice were blocked at meiotic stage. The expression of meiosis associated genes was reduced in Prmt5(Δ/f); Stra8-Cre testes compared to control testes at P10. γH2AX was detected in sex body of control germ cells at P12, whereas multiple foci were observed in Prmt...
The transforming growth factor beta (TGF-β) signaling pathway is a tumor-suppressor pathway that ... more The transforming growth factor beta (TGF-β) signaling pathway is a tumor-suppressor pathway that is commonly inactivated in colorectal cancer (CRC). The inactivation of TGFBR2 is the most common genetic event affecting the TGF-β signaling pathway. However, the mechanism by which cancer cells downregulate TGFBR2 is unclear. In this study, we found that the TGFBR2 protein levels were consistently upregulated in CRC tissues, whereas its mRNA levels varied in these tissues, suggesting that a post-transcriptional mechanism is involved in the regulation of TGFBR2. Because microRNAs (miRNAs) are powerful post-transcriptional regulators of gene expression, we performed bioinformatic analyses to search for miRNAs that potentially target TGFBR2. We identified the specific targeting site of miR-135b in the 3'-untranslated region (3'-UTR) of TGFBR2. We further identified an inverse correlation between the levels of miR-135b and TGFBR2 protein, but not mRNA, in CRC tissue samples. By ove...
Although human cancers have heterogeneous combinations of altered oncogenes, some crucial genes a... more Although human cancers have heterogeneous combinations of altered oncogenes, some crucial genes are universally dysregulated in most cancers. One such gene, FEAT (faint expression in normal tissues, aberrant overexpression in tumors), is uniformly overexpressed in a variety of human cancers and plays an important role in tumorigenesis by suppressing apoptosis. However, the precise molecular mechanism through which FEAT is upregulated during tumorigenesis remains largely unknown. In this study, we used bioinformatic analyses to search for miRNAs that potentially target FEAT. We examined the expression of FEAT protein level by western blotting and miR-16 level by qRT-PCR assay. Cancer cell lines (A549, MCF-7 and Huh-7) with miR-16 upregulation and FEAT silencing were established and the effects on apoptosis of cancer cells in vitro were assessed. Luciferase reporter assay was also performed to investigate the interaction between miR-16 and FEAT. We identified a specific target site fo...
Previous studies reported that the expression of miR-23b-27b cluster was downregulated in embryon... more Previous studies reported that the expression of miR-23b-27b cluster was downregulated in embryonic brain cortices during hypoxia-induced neuronal apoptosis. However, the mechanism underlying this downregulation is not completely understood. Here, we report that the transcription factor c-Myc plays an important role in regulating the expression of miR-23b-27b cluster during hypoxia. First, the c-Myc protein level was significantly elevated in embryonic brain cortices in a mouse model of fetal distress. Second, forced overexpression or knockdown of c-Myc could suppress or increase the expression of miR-23b-27b cluster polynucleotides. Third, we identified 2 conserved c-Myc binding sites (E-boxes) in the enhancer and promoter regions of miR-23b-27b cluster in the mouse genome. Finally, we showed that elevated c-Myc expression led to an increase in the Apaf-1 level by suppressing miR-23b-27b cluster expression and that this enhanced neuronal sensitivity to apoptosis. In summary, our st...
The study was designed to determine the differential protein expression of Caco-2 cells treated w... more The study was designed to determine the differential protein expression of Caco-2 cells treated with different forms of selenium including sodium selenite, selenomethionine (Se-Met), and selenium nanoparticles (nano-Se). Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS) were used to identify the differentially expressed proteins. The results indicated that seven protein spots, ubiquitin-conjugating enzyme E2 (E2), glutathione synthetases (GS), triosephosphate isomerase (TSP), T-complex protein 1 subunit zeta (TCPZ), lamin-B1, heterogeneous nuclear ribonucleoprotein F (hnRNP F), and superoxide dismutase [Cu-Zn] (Cu, Zn-SOD) were significantly different among all the groups. According to the order of control, sodium selenite, Se-Met, and Nano-Se, the expression levels of two proteins (E2 and GS) increased and the other differential proteins were reverse. Except for E2, there were no significant differences in other protein expressions between the ...
International braz j urol : official journal of the Brazilian Society of Urology
To evaluate the effectivity and safety of percutaneous nephrolithotomy (PCNL) in the treatment of... more To evaluate the effectivity and safety of percutaneous nephrolithotomy (PCNL) in the treatment of solitary kidney with staghorn stones in prone position or in completely supine position. We retrospectively reviewed the records of 18 patients with staghorn stones in a solitary kidney treated with PCNL. 12 patients underwent PCNL in prone position (group A). 6 patients underwent PCNL in completely supine position (group B). Demographic data, number of accesses, operating time, stone free rate, hemoglobin values, hospital stay and complications were studied. Serum creatinine, systolic and diastolic blood pressure, and new onset hypertension were determined preoperatively and postoperatively at 3 months. No blood transfusions were required and no abdominal or thoracic organ injuries were reported in both groups. The mean operative time was 104 minutes (range: 72-145 minutes) and 128 minutes (range: 80-170 minutes), respectively. The I stage stone free rate was 91.7 % and 83.3 %, respect...
Journal of bioinformatics and computational biology, 2009
In this paper, data mining is used to analyze the data on the differentiation of mammalian Mesenc... more In this paper, data mining is used to analyze the data on the differentiation of mammalian Mesenchymal Stem Cells (MSCs), aiming at discovering known and hidden rules governing MSC differentiation, following the establishment of a web-based public database containing experimental data on the MSC proliferation and differentiation. To this effect, a web-based public interactive database comprising the key parameters which influence the fate and destiny of mammalian MSCs has been constructed and analyzed using Classification Association Rule Mining (CARM) as a data-mining technique. The results show that the proposed approach is technically feasible and performs well with respect to the accuracy of (classification) prediction. Key rules mined from the constructed MSC database are consistent with experimental observations, indicating the validity of the method developed and the first step in the application of data mining to the study of MSCs.
In mammals, germ cells undergo massive epigenetic remodeling during fetal development. However, t... more In mammals, germ cells undergo massive epigenetic remodeling during fetal development. However, the physiological functions of epigenetic modification in germ cell development remain unclear. In this study, we found that protein arginine methyltransferase 5 (Prmt5) was abundantly expressed in the germ cells of both male and female gonads. Deletion of Prmt5 by crossing with Tnap-Cre mice resulted in germ cell depletion in adult mice. Germ cell loss was first observed between E12.5 and E13.5, and very few of these cells remained at birth. Oct4, Sox2, and Nanog were abundantly expressed in Prmt5-deficient germ cells at E13.5 and E15.5, whereas the expression of these genes was dramatically decreased in control germ cells. Interestingly, the expression of meiosis-associated genes was virtually absent in Prmt5-deficient female germ cells at E13.5, whereas the expression of other germ cell-specific genes was not changed. Further study revealed that H4R3me2s was completely absent after Prm...
Partial dislocation emission from grain boundaries in metals with medium-to-high stacking fault ... more Partial dislocation emission from grain boundaries in metals with medium-to-high stacking fault energies is observed primarily in the grain size range of a few tens of nanometers. Here we report that a reduction in the stacking fault energy permits the emission of partial dislocations from grain boundaries in ultrafine-grained materials with grain sizes significantly larger than 100 nm and this produces twinning. Such twins are effective in increasing the dislocation storage capacity, which may be used to improve the ductility.
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban
This paper studied the effects of probiotics on the sediment of Penaeus vannamei pond during 117 ... more This paper studied the effects of probiotics on the sediment of Penaeus vannamei pond during 117 days of culture period. The results showed that probiotics application significantly decreased the concentrations of total nitrogen, total phosphorous, and sulfide in sediment, but no significant difference was observed in total plate count (TPC) of microbes between treated and control ponds. The final average presumptive vibrio count (PVC) of treated pond sediment (3.65 x 10(3) cfu x g(-1)) was significantly lower than that of the control (1.16 x 10(5) cfu x g(-1)), while the average number of BS (Bacillus), AB (ammonifying bacteria), PSOB (presumptive sulphur oxidizing bacteria) and SRB (sulphur reducing bacteria) in treated pond sediment was higher than that of the control. These data showed that probiotics could decrease the nutrients (nitrogen, phosphate and sulfur) accumulation and improve the composition of bacterial populations in pond sediment, and thus, supply a good sediment e...
ABSTRACT Effect of viable Bacillus coagulans as a dietary probiotic on the growth performance, su... more ABSTRACT Effect of viable Bacillus coagulans as a dietary probiotic on the growth performance, survivorship, immune response, and meat quality of the common carp, Cyprinus carpio, was investigated. Three treatments (T-1, T-2, and T-3) and a control, each with three replicates, were established. T-1, T-2, and T-3 groups were fed with diets containing different levels of probiotic (1 × 107 cfu/g, 2 × 107 cfu/g, and 4 × 107 cfu/g, respectively). After 45 d, the fish fed with probiotic had significantly higher (P < 0.05) daily weight gain compared to that of the control group. Significant increases (P < 0.05) in final weight, relative weight gain rate, lysozyme, myeloperoxidase, and respiratory burst activities were obtained in the T-2 and T-3 compared with those of the control. Fish in the control group showed the lowest (P < 0.05) content of complement component 3. Significantly (P < 0.05) improved contents of crude fat, inosine, and inosinic acid were observed in the T-2 and T-3. Our results indicated that the use of B. coagulans as a dietary probiotic for the common carp could improve growth performance, meat quality, and induce a positive modulation on immune response.
Determination of the elastic modulus of nanostructures with sizes at several nm range is challeng... more Determination of the elastic modulus of nanostructures with sizes at several nm range is challenge. In this study, we designed an experiment to measure the elastic modulus of amorphous Al2O3 films with thicknesses varying between 2 and 25 nm. The amorphous Al2O3 was in the form of a shell, wrapped around GaAs nanowires, thereby forming an effective core/shell structure. The GaAs cores comprised a single crystal structure with a diameter of 100 nm. Combined in-situ compression transmission electron microscopy and finite element analysis (FEA) were used to evaluate the elastic modulus of the overall core/shell nanowires. A core/shell model was applied to de-convolute the elastic modulus of the Al2O3 shell from the core. The results indicate that the elastic modulus of amorphous Al2O3 increases significantly when the thickness of the layer is smaller than 5 nm. This novel nanoscale materials can be attributed to the re-construction of bonding at the surface of the material, coupled wit...
Droplet epitaxy is an important method to produce epitaxial semiconductor quantum dots (QDs). Dro... more Droplet epitaxy is an important method to produce epitaxial semiconductor quantum dots (QDs). Droplet epitaxy of III-V QDs comprises group III elemental droplet deposition and the droplet crystallization through the introduction of group V elements. Here, we report that, in the droplet epitaxy of InAs/GaAs(001) QDs using metal-organic chemical vapor deposition, significant elemental diffusion from the substrate to In droplets occurs, resulting in the formation of In(Ga)As crystals, before As flux is provided. The supply of As flux suppresses the further elemental diffusion from the substrate and promotes surface migration, leading to large island formation with a low island density.
Glass transition temperature and plastic yield strength are known to be correlated in metallic gl... more Glass transition temperature and plastic yield strength are known to be correlated in metallic glasses. We have observed by in situ synchrotron high energy X-ray diffraction anisotropy of the thermal expansion behavior in the nearest neighbor and second nearest neighbor atomic distances in the building blocks of ZrCuNiAl based bulk metallic glass, leading inevitably to shear. Mechanical yielding of the latter on the atomic scale leads to the glass transition and the increase of the free volume. These experimental results uncover the mechanism, how glass transition and yield strength are linked.
Transactions on Machine Learning and Data Mining, 2008
Classification Association Rule Mining (CARM) is an approach to classifier generation that builds... more Classification Association Rule Mining (CARM) is an approach to classifier generation that builds an Association Rule Mining based classifier using Classification Association Rules (CARs). Regardless of which particular CARM algorithm is used, a similar set of CARs is always generated from data, and a classifier is usually presented as an ordered list of CARs, based on a selected rule ordering
During germ cell development, epigenetic modifications undergo extensive remodeling. Abnormal epi... more During germ cell development, epigenetic modifications undergo extensive remodeling. Abnormal epigenetic modifications usually result in germ cell loss and reproductive defect. Prmt5 (Protein arginine methyltransferase 5) encodes a protein arginine methyltransferase which has been demonstrated to play important roles in germ cell development during embryonic stages. In the present study, we found that Prmt5 was also abundantly expressed in male germ cells after birth. Inactivation of this gene by crossing with Stra8-Cre transgenic mice resulted in germ cell loss during spermatogenesis. Further study revealed that the germ cell development was grossly normal before P10. However, most of the germ cells in Prmt5(Δ/f); Stra8-Cre mice were blocked at meiotic stage. The expression of meiosis associated genes was reduced in Prmt5(Δ/f); Stra8-Cre testes compared to control testes at P10. γH2AX was detected in sex body of control germ cells at P12, whereas multiple foci were observed in Prmt...
The transforming growth factor beta (TGF-β) signaling pathway is a tumor-suppressor pathway that ... more The transforming growth factor beta (TGF-β) signaling pathway is a tumor-suppressor pathway that is commonly inactivated in colorectal cancer (CRC). The inactivation of TGFBR2 is the most common genetic event affecting the TGF-β signaling pathway. However, the mechanism by which cancer cells downregulate TGFBR2 is unclear. In this study, we found that the TGFBR2 protein levels were consistently upregulated in CRC tissues, whereas its mRNA levels varied in these tissues, suggesting that a post-transcriptional mechanism is involved in the regulation of TGFBR2. Because microRNAs (miRNAs) are powerful post-transcriptional regulators of gene expression, we performed bioinformatic analyses to search for miRNAs that potentially target TGFBR2. We identified the specific targeting site of miR-135b in the 3'-untranslated region (3'-UTR) of TGFBR2. We further identified an inverse correlation between the levels of miR-135b and TGFBR2 protein, but not mRNA, in CRC tissue samples. By ove...
Although human cancers have heterogeneous combinations of altered oncogenes, some crucial genes a... more Although human cancers have heterogeneous combinations of altered oncogenes, some crucial genes are universally dysregulated in most cancers. One such gene, FEAT (faint expression in normal tissues, aberrant overexpression in tumors), is uniformly overexpressed in a variety of human cancers and plays an important role in tumorigenesis by suppressing apoptosis. However, the precise molecular mechanism through which FEAT is upregulated during tumorigenesis remains largely unknown. In this study, we used bioinformatic analyses to search for miRNAs that potentially target FEAT. We examined the expression of FEAT protein level by western blotting and miR-16 level by qRT-PCR assay. Cancer cell lines (A549, MCF-7 and Huh-7) with miR-16 upregulation and FEAT silencing were established and the effects on apoptosis of cancer cells in vitro were assessed. Luciferase reporter assay was also performed to investigate the interaction between miR-16 and FEAT. We identified a specific target site fo...
Previous studies reported that the expression of miR-23b-27b cluster was downregulated in embryon... more Previous studies reported that the expression of miR-23b-27b cluster was downregulated in embryonic brain cortices during hypoxia-induced neuronal apoptosis. However, the mechanism underlying this downregulation is not completely understood. Here, we report that the transcription factor c-Myc plays an important role in regulating the expression of miR-23b-27b cluster during hypoxia. First, the c-Myc protein level was significantly elevated in embryonic brain cortices in a mouse model of fetal distress. Second, forced overexpression or knockdown of c-Myc could suppress or increase the expression of miR-23b-27b cluster polynucleotides. Third, we identified 2 conserved c-Myc binding sites (E-boxes) in the enhancer and promoter regions of miR-23b-27b cluster in the mouse genome. Finally, we showed that elevated c-Myc expression led to an increase in the Apaf-1 level by suppressing miR-23b-27b cluster expression and that this enhanced neuronal sensitivity to apoptosis. In summary, our st...
The study was designed to determine the differential protein expression of Caco-2 cells treated w... more The study was designed to determine the differential protein expression of Caco-2 cells treated with different forms of selenium including sodium selenite, selenomethionine (Se-Met), and selenium nanoparticles (nano-Se). Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS) were used to identify the differentially expressed proteins. The results indicated that seven protein spots, ubiquitin-conjugating enzyme E2 (E2), glutathione synthetases (GS), triosephosphate isomerase (TSP), T-complex protein 1 subunit zeta (TCPZ), lamin-B1, heterogeneous nuclear ribonucleoprotein F (hnRNP F), and superoxide dismutase [Cu-Zn] (Cu, Zn-SOD) were significantly different among all the groups. According to the order of control, sodium selenite, Se-Met, and Nano-Se, the expression levels of two proteins (E2 and GS) increased and the other differential proteins were reverse. Except for E2, there were no significant differences in other protein expressions between the ...
International braz j urol : official journal of the Brazilian Society of Urology
To evaluate the effectivity and safety of percutaneous nephrolithotomy (PCNL) in the treatment of... more To evaluate the effectivity and safety of percutaneous nephrolithotomy (PCNL) in the treatment of solitary kidney with staghorn stones in prone position or in completely supine position. We retrospectively reviewed the records of 18 patients with staghorn stones in a solitary kidney treated with PCNL. 12 patients underwent PCNL in prone position (group A). 6 patients underwent PCNL in completely supine position (group B). Demographic data, number of accesses, operating time, stone free rate, hemoglobin values, hospital stay and complications were studied. Serum creatinine, systolic and diastolic blood pressure, and new onset hypertension were determined preoperatively and postoperatively at 3 months. No blood transfusions were required and no abdominal or thoracic organ injuries were reported in both groups. The mean operative time was 104 minutes (range: 72-145 minutes) and 128 minutes (range: 80-170 minutes), respectively. The I stage stone free rate was 91.7 % and 83.3 %, respect...
Journal of bioinformatics and computational biology, 2009
In this paper, data mining is used to analyze the data on the differentiation of mammalian Mesenc... more In this paper, data mining is used to analyze the data on the differentiation of mammalian Mesenchymal Stem Cells (MSCs), aiming at discovering known and hidden rules governing MSC differentiation, following the establishment of a web-based public database containing experimental data on the MSC proliferation and differentiation. To this effect, a web-based public interactive database comprising the key parameters which influence the fate and destiny of mammalian MSCs has been constructed and analyzed using Classification Association Rule Mining (CARM) as a data-mining technique. The results show that the proposed approach is technically feasible and performs well with respect to the accuracy of (classification) prediction. Key rules mined from the constructed MSC database are consistent with experimental observations, indicating the validity of the method developed and the first step in the application of data mining to the study of MSCs.
In mammals, germ cells undergo massive epigenetic remodeling during fetal development. However, t... more In mammals, germ cells undergo massive epigenetic remodeling during fetal development. However, the physiological functions of epigenetic modification in germ cell development remain unclear. In this study, we found that protein arginine methyltransferase 5 (Prmt5) was abundantly expressed in the germ cells of both male and female gonads. Deletion of Prmt5 by crossing with Tnap-Cre mice resulted in germ cell depletion in adult mice. Germ cell loss was first observed between E12.5 and E13.5, and very few of these cells remained at birth. Oct4, Sox2, and Nanog were abundantly expressed in Prmt5-deficient germ cells at E13.5 and E15.5, whereas the expression of these genes was dramatically decreased in control germ cells. Interestingly, the expression of meiosis-associated genes was virtually absent in Prmt5-deficient female germ cells at E13.5, whereas the expression of other germ cell-specific genes was not changed. Further study revealed that H4R3me2s was completely absent after Prm...
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Papers by Yanbo Wang