Alopecia in Harlequin mutant mice is associated with reduced AIF protein levels and expression of retroviral elements

AbstractWe investigated the contribution of apoptosis-inducing factor (AIF), a key regulator of mitochondrial biogenesis, in supporting hair growth. We report that pelage abnormalities developed during hair follicle (HF) morphogenesis in Harlequin (Hq) mutant mice. Fragility of the hair cortex was associated with decreased expression of genes encoding structural hair proteins, though key transcriptional regulators of HF development were expressed at normal levels. Notably, Aifm1 (R200 del) knockin males and Aifm1(R200 del)/Hq females showed minor hair defects, despite substantially reduced AIF levels. Furthermore, we cloned the integrated ecotropic provirus of the Aifm1Hq allele. We found that its overexpression in wild-type keratinocyte cell lines led to down-regulation of HF-specific Krt84 and Krtap3-3 genes without altering Aifm1 or epidermal Krt5 expression. Together, our findings imply that pelage paucity in Hq mutant mice is mechanistically linked to severe AIF deficiency and is associated with the expression of retroviral elements that might potentially influence the transcriptional regulation of structural hair proteins.

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Evaluation of the effects of sdiA, a luxR homologue, on adherence and motility of Escherichia coli O157 : H7

Microbiology ◽

10.1099/mic.0.034330-0 ◽

2010 ◽

Vol 156 (5) ◽

pp. 1303-1312 ◽

Cited By ~ 37

Author(s):

Vijay K. Sharma ◽

Shawn M. D. Bearson ◽

Bradley L. Bearson

Keyword(s):

Escherichia Coli ◽

Epithelial Cells ◽

Mutant Strain ◽

Regulatory Networks ◽

Double Mutant ◽

Negative Regulator ◽

Wild Type ◽

Reverse Transcription Pcr ◽

Expression Of Genes ◽

Genes Encoding

Quorum-sensing (QS) signalling pathways are important regulatory networks for controlling the expression of genes promoting adherence of enterohaemorrhagic Escherichia coli (EHEC) O157 : H7 to epithelial cells. A recent study has shown that EHEC O157 : H7 encodes a luxR homologue, called sdiA, which upon overexpression reduces the expression of genes encoding flagellar and locus of enterocyte effacement (LEE) proteins, thus negatively impacting on the motility and intimate adherence phenotypes, respectively. Here, we show that the deletion of sdiA from EHEC O157 : H7 strain 86-24, and from a hha (a negative regulator of ler) mutant of this strain, enhanced bacterial adherence to HEp-2 epithelial cells of the sdiA mutant strains relative to the strains containing a wild-type copy of sdiA. Quantitative reverse transcription PCR showed that the expression of LEE-encoded genes ler, espA and eae in strains with the sdiA deletions was not significantly different from that of the strains wild-type for sdiA. Similarly, no additional increases in the expression of LEE genes were observed in a sdiA hha double mutant strain relative to that observed in the hha deletion mutant. While the expression of fliC, which encodes flagellin, was enhanced in the sdiA mutant strain, the expression of fliC was reduced by several fold in the hha mutant strain, irrespective of the presence or absence of sdiA, indicating that the genes sdiA and hha exert opposing effects on the expression of fliC. The strains with deletions in sdiA or hha showed enhanced expression of csgA, encoding curlin of the curli fimbriae, with the expression of csgA highest in the sdiA hha double mutant, suggesting an additive effect of these two gene deletions on the expression of csgA. No significant differences were observed in the expression of the genes lpfA and fimA of the operons encoding long polar and type 1 fimbriae in the sdiA mutant strain. These data indicate that SdiA has no significant effect on the expression of LEE genes, but that it appears to act as a strong repressor of genes encoding flagella and curli fimbriae, and the alleviation of the SdiA-mediated repression of these genes in an EHEC O157 : H7 sdiA mutant strain contributes to enhanced bacterial motility and increased adherence to HEp-2 epithelial cells.

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Aging alters histone H3 lysine 4 methylation in mouse germinal vesicle stage oocytes

Reproduction Fertility and Development ◽

10.1071/rd13293 ◽

2015 ◽

Vol 27 (2) ◽

pp. 419 ◽

Cited By ~ 13

Author(s):

Gen-Bao Shao ◽

Jie Wang ◽

Liu-Ping Zhang ◽

Chao-Yang Wu ◽

Jie Jin ◽

...

Keyword(s):

Histone Acetylation ◽

Histone H3 ◽

Germinal Vesicle ◽

Retinol Binding Protein ◽

Oocyte Competence ◽

Protein Levels ◽

Expression Of Genes ◽

Genes Encoding ◽

Maternal Aging ◽

Old Mice

Decreasing oocyte competence with maternal aging is a major factor in mammalian infertility. One of the factors contributing to this infertility is changes to chromatin modifications, such as histone acetylation in old MII stage oocytes. Recent studies indicate that changes in histone acetylation at MII arise at the germinal vesicle (GV) stage. We hypothesised that histone methylation could also change in old GV oocytes. To test this hypothesis, we examined mono-, di- and trimethylation of histone H3 lysine 4 (H3K4 me1, me2 and me3, respectively) in young and older oocytes from 6–8- and 42–44-week-old mice, respectively. We found that H3K4 me2 and me3 decreased in older compared with young GV oocytes (100% vs 81% and 100% vs 87%, respectively; P < 0.05). H3K4 me2 later increased in older MII oocytes (21% vs 56%; P < 0.05). We also examined the expression of genes encoding the H3K4 demethylases lysine (K)-specific demethylase 1A (Kdm1a) and retinol binding protein 2 (Rbp2). Expression of Kdm1a increased at both the mRNA and protein levels in older GV oocytes, but decreased in older MII oocytes (P < 0.05), and was negatively correlated with H3K4 me2 levels. Conversely, expression of Rbp2 mRNA and protein decreased in older GV oocytes (P < 0.05), and this was not correlated with H3K4 me3 levels. Finally, we showed that inhibition of Kdm1a of older oocytes at the GV stage restored levels of H3K4 me2 at the MII stage to those seen in ‘young’ oocytes (41% vs 38%; P > 0.05). These results suggest that changes in expression of H3K4 me2 and Kdm1a in older GV oocytes may represent a molecular mechanism underlying human infertility caused by aging.

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Redox-Dependent Gene Regulation inRhodobacter sphaeroides 2.4.1T: Effects on Dimethyl Sulfoxide Reductase (dor) Gene Expression

Journal of Bacteriology ◽

10.1128/jb.180.21.5612-5618.1998 ◽

1998 ◽

Vol 180 (21) ◽

pp. 5612-5618 ◽

Cited By ~ 25

Author(s):

Nigel J. Mouncey ◽

Samuel Kaplan

Keyword(s):

Gene Expression ◽

Dimethyl Sulfoxide ◽

Type Strain ◽

Wild Type Strain ◽

Strictly Aerobic ◽

Wild Type ◽

Dmso Reductase ◽

Regulatory Cascade ◽

Expression Of Genes ◽

Genes Encoding

ABSTRACT The ability of Rhodobacter sphaeroides2.4.1T to respire anaerobically with the alternative electron acceptor dimethyl sulfoxide (DMSO) or trimethylamineN-oxide (TMAO) is manifested by the molybdoenzyme DMSO reductase, which is encoded by genes of the dor locus. Previously, we have demonstrated that dor expression is regulated in response to lowered oxygen tensions and the presence of DMSO or TMAO in the growth medium. Several regulatory proteins have been identified as key players in this regulatory cascade: FnrL, DorS-DorR, and DorX-DorY. To further examine the role of redox potentiation in the regulation of dor expression, we measured DMSO reductase synthesis and β-galactosidase activity fromdor::lacZ fusions in strains containing mutations in the redox-active proteins CcoP and RdxB, which have previously been implicated in the generation of a redox signal affecting photosynthesis gene expression. Unlike the wild-type strain, both mutants were able to synthesize DMSO reductase under strictly aerobic conditions, even in the absence of DMSO. When cells were grown photoheterotrophically, dorC::lacZexpression was stimulated by increasing light intensity in the CcoP mutant, whereas it is normally repressed in the wild-type strain under such conditions. Furthermore, the expression of genes encoding the DorS sensor kinase and DorR response regulator proteins was also affected by the ccoP mutation. By using CcoP-DorR and CcoP-DorY double mutants, it was shown that the DorR protein is strictly required for altered dor expression in CcoP mutants. These results further demonstrate a role for redox-generated responses in the expression of genes encoding DMSO reductase in R. sphaeroides and identify the DorS-DorR proteins as a redox-dependent regulatory system controlling dorexpression.

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The Metabolic Reprogramming of Frem2 Mutant Mice Embryos in Cryptophthalmos Development

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2020.625492 ◽

2021 ◽

Vol 8 ◽

Author(s):

Xiayin Zhang ◽

Ruixin Wang ◽

Ting Wang ◽

Xulin Zhang ◽

Meimei Dongye ◽

...

Keyword(s):

Metabolic Reprogramming ◽

Mutant Mice ◽

Compound Heterozygous ◽

Rna Seq ◽

Targeted Metabolomics ◽

Expression Of Genes ◽

Fetal Mice ◽

Genes Encoding ◽

Go Terms ◽

Increased Susceptibility

BackgroundCryptophthalmos is characterized by congenital ocular dysplasia with eyelid malformation. The pathogenicity of mutations in genes encoding components of the FRAS1/FREM protein complex is well established, but the underlying pathomechanisms of this disease are still unclear. In the previous study, we generated mice carrying Frem2R725X/R2156W compound heterozygous mutations using CRISPR/Cas9 and showed that these mice recapitulated the human cryptophthalmos phenotype.MethodsIn this study, we tracked changes in the metabolic profile of embryos and expression of metabolism-related genes in Frem2 mutant mice on E13.5 compared with wild-type mice. RNA sequencing (RNA-seq) was utilized to decipher the differentiated expression of genes associated with metabolism. Untargeted metabolomics and targeted metabolomics analyses were performed to detect and verify the shifts in the composition of the embryonic metabolome.ResultsDifferentially expressed genes participating in amino acid metabolism and energy metabolism were observed by RNA-seq. Transcriptomic analysis suggests that 821 (39.89%) up-regulated genes and 320 (32.99%) down-regulated genes were involved in the metabolic process in the enriched GO terms. A total of 92 significantly different metabolites were identified including creatine, guanosine 5′-monophosphate, cytosine, cytidine 5′-monophosphate, adenine, and L-serine. Interestingly, major shifts related to ATP binding cassette transporters (ABC transporters) and the biosynthesis of amino acids in the composition of the embryonic metabolome were observed by KEGG metabolic analysis, indicating that these pathways could also be involved in the pathogenesis of cryptophthalmos.ConclusionWe demonstrate that Frem2 mutant fetal mice have increased susceptibility to the disruption of eye morphogenesis in association with distinct transcriptomic and metabolomic signatures. Our findings suggest that the metabolomic signature established before birth may play a role in mediating cryptophthalmos in Frem2 mutant mice, which may have important implications for the pathogenesis of cryptophthalmos.

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BIOTIN ATTACHMENT DOMAIN-CONTAINING proteins, inhibitors of ACCase, are regulated by WRINKLED1

10.1101/634550 ◽

2019 ◽

Author(s):

Hui Liu ◽

Zhiyang Zhai ◽

Kate Kuczynski ◽

Jantana Keereetaweep ◽

Jorg Schwender ◽

...

Keyword(s):

Acid Synthesis ◽

Lipid Homeostasis ◽

Wild Type ◽

Short Root ◽

Protein Levels ◽

Genes Encoding ◽

Synthetic Capacity ◽

Nanomolar Range ◽

Indole 3 Acetic Acid

AbstractWRINKLED1 (WRI1) is a transcriptional activator that binds to AW boxes in the promoters of many genes from central metabolism and FA synthesis, resulting in their transcription. BIOTIN ATTACHMENT DOMAIN-CONTAINING (BADC) proteins are homologs of BIOTIN CARBOXYL CARRIER PROTEIN (BCCP) that lack a biotin-attachment domain and are therefore inactive. In the presence of excess FA, BADC1 and BADC3 are primarily responsible for the observed long-term irreversible inhibition of ACETYL-COA CARBOXYLASE (ACCase), and consequently FA synthesis. Purified WRI1 bound with high affinity (Kds in the low nanomolar range) to canonical AW-boxes from the promoters of all three BADC genes. Consistent with this observation, the expression of BADC1, BADC2 and BADC3 genes and BADC1 protein levels were reduced in wri1-1 relative to wild type (WT), and BADCs gene expression and BADC1 protein levels also were elevated upon WRI1 overexpression. The double mutant badc1badc2 phenocopied wri1-1 with respect to both reduction in root length, and elevation of indole-3-acetic acid-Asp (IAA-Asp) levels relative to WT. Overexpression of BADC1 in wri1-1 decreased its IAA-Asp and partially rescued its short-root phenotype demonstrating a role for BADCs in seedling establishment. That WRI1 positively regulates genes encoding both FA synthesis and BADCs i.e., conditional inhibitors of FA synthesis, represents a coordinated mechanism to achieve lipid homeostasis in which plants couple the transcription their FA synthetic capacity with their capacity to biochemically downregulate it.One sentence summaryWRI1 regulates genes encoding both fatty acid synthesis and inhibitors of FA synthesis (BADCs), creating a lipid homeostatic mechanism in which the transcription of FA synthetic capacity is coordinated with the capacity to biochemically downregulate FA synthesis.

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HosA, a Member of the SlyA Family, Regulates Motility in Enteropathogenic Escherichia coli

Infection and Immunity ◽

10.1128/iai.73.3.1684-1694.2005 ◽

2005 ◽

Vol 73 (3) ◽

pp. 1684-1694 ◽

Cited By ~ 9

Author(s):

Maria-José Ferrándiz ◽

Keith Bishop ◽

Paul Williams ◽

Helen Withers

Keyword(s):

Escherichia Coli ◽

Transcriptional Regulators ◽

Positive Control ◽

Broth Culture ◽

Wild Type ◽

Mobility Shift ◽

E Coli ◽

Protein Levels ◽

K 12 ◽

Electrophoretic Mobility Shift Assays

ABSTRACT In enteropathogenic and enterohemorraghic Escherichia coli (EPEC and EHEC), two members of the SlyA family of transcriptional regulators have been identified as SlyA. Western blot analysis of the wild type and the corresponding hosA and slyA deletion mutants indicated that SlyA and HosA are distinct proteins whose expression is not interdependent. Of 27 different E. coli strains (EPEC, EHEC, enteroinvasive, enteroaggregative, uropathogenic, and commensal) examined, 14 were positive for both genes and proteins. To investigate hosA expression, a hosA::luxCDABE reporter gene fusion was constructed. hosA expression was significantly reduced in the hosA but not the slyA mutant and was influenced by temperature, salt, and pH. In contrast to SlyA, HosA did not activate the cryptic E. coli K-12 hemolysin ClyA. Mutation of hosA did not influence type III secretion, the regulation of the LEE1 and LEE4 operons, or the ability of E2348/69 to form attaching-and-effacing lesions on intestinal epithelial cells. HosA is, however, involved in the temperature-dependent positive control of motility on swim plates and regulates fliC expression and FliC protein levels. In electrophoretic mobility shift assays, purified HosA protein bound specifically to the fliC promoter, indicating that HosA directly modulates flagellin expression. While direct examination of flagellar structure and the motile behavior of individual hosA cells grown in broth culture at 30°C did not reveal any obvious differences, hosA mutants, unlike the wild type, clumped together, forming nonmotile aggregates which could account for the markedly reduced motility of the hosA mutant on swim plates at 30°C. We conclude that SlyA and HosA are independent transcriptional regulators that respond to different physicochemical cues to facilitate the environmental adaptation of E. coli.

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WhiB5, a Transcriptional Regulator That Contributes to Mycobacterium tuberculosis Virulence and Reactivation

Infection and Immunity ◽

10.1128/iai.06328-11 ◽

2012 ◽

Vol 80 (9) ◽

pp. 3132-3144 ◽

Cited By ~ 35

Author(s):

Stefano Casonato ◽

Axel Cervantes Sánchez ◽

Hirohito Haruki ◽

Monica Rengifo González ◽

Roberta Provvedi ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Chronic Infection ◽

Null Mutant ◽

Wild Type ◽

Secretion Systems ◽

Content Type ◽

Type Vii Secretion ◽

Expression Of Genes ◽

Genes Encoding

ABSTRACTThe proteins belonging to the WhiB superfamily are small global transcriptional regulators typical of actinomycetes. In this paper, we characterize the role of WhiB5, aMycobacterium tuberculosisprotein belonging to this superfamily. A null mutant was constructed inM. tuberculosisH37Rv and was shown to be attenuated during both progressive and chronic mouse infections. Mice infected with the mutant had smaller bacillary burdens in the lungs but a larger inflammatory response, suggesting a role of WhiB5 in immunomodulation. Most interestingly, thewhiB5mutant was not able to resume growth after reactivation from chronic infection, suggesting that WhiB5 controls the expression of genes involved in this process. The mutant was also more sensitive than the wild-type parental strain toS-nitrosoglutathione (GSNO) and was less metabolically active following prolonged starvation, underscoring the importance of GSNO and starvation in development and maintenance of chronic infection. DNA microarray analysis identified 58 genes whose expression is influenced by WhiB5, includingsigM, encoding an alternative sigma factor, and genes encoding the constituents of two type VII secretion systems, namely, ESX-2 and ESX-4.

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Iron-Dependent Cytochrome c1 Expression Is Mediated by the Status of Heme in Bradyrhizobium japonicum

Journal of Bacteriology ◽

10.1128/jb.187.15.5084-5089.2005 ◽

2005 ◽

Vol 187 (15) ◽

pp. 5084-5089 ◽

Cited By ~ 7

Author(s):

Tao Gao ◽

Mark R. O'Brian

Keyword(s):

Bradyrhizobium Japonicum ◽

Aminolevulinic Acid ◽

Iron Status ◽

Covalent Binding ◽

Dependent Manner ◽

Wild Type ◽

Prosthetic Group ◽

Protein Levels ◽

Genes Encoding ◽

In The Wild

ABSTRACT The heme prosthetic group of heme proteins contains iron, which can be a limiting nutrient. Here, we show that cytochrome c 1 protein from Bradyrhizobium japonicum was strongly affected by the iron status, with low expression in cells grown under iron limitation. This control was not affected in mutants encoding the iron regulator Irr or Fur. Furthermore, cytochrome c 1 mRNA was not influenced by the iron status, suggesting control at a posttranscriptional step. Cytochrome c 1 protein levels were very low in mutants defective in the genes encoding δ-aminolevulinic acid (ALA) synthase and ferrochelatase, enzymes that catalyze the first and final steps of the heme biosynthetic pathway, respectively. Iron-dependent cytochrome c 1 expression was restored in the ALA synthase mutant by supplementation of the medium with the heme precursor ALA. Supplementation with heme resulted in high levels of cytochrome c 1 protein in the wild type and in both mutants, but expression was no longer iron dependent. Cytochrome c 1 is synthesized as a protein precursor fused with cytochrome b. A plasmid-borne construct encoding only cytochrome c 1 was expressed in an iron- and heme-dependent manner similar to that of the wild-type gene, indicating that control by those effectors is not linked to posttranslational processing of the fusion protein. Mutation of the cytochrome c 1 cysteines involved in covalent binding to heme nearly abolished immunodetectable protein. Thus, defects in heme synthesis or heme binding abrogate cytochrome c 1 accumulation, apparently due to protein degradation. We suggest that iron-dependent cytochrome c 1 expression is mediated by heme availability for heme protein formation

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Supplemental Cellular Protection by a Carotenoid Extends Lifespan via Ins/IGF-1 Signaling inCaenorhabditis elegans

Oxidative Medicine and Cellular Longevity ◽

10.1155/2011/596240 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 26

Author(s):

Koumei Yazaki ◽

Chinatsu Yoshikoshi ◽

Satoru Oshiro ◽

Sumino Yanase

Keyword(s):

Model Organism ◽

Lifespan Extension ◽

Cell Organelle ◽

Wild Type ◽

Marine Animals ◽

Cellular Protection ◽

C Elegans ◽

Expression Of Genes ◽

Genes Encoding ◽

In The Wild

Astaxanthin (AX), which is produced by some marine animals, is a type of carotenoid that has antioxidative properties. In this study, we initially examined the effects of AX on the aging of a model organismC. elegansthat has the conserved intracellular pathways related to mammalian longevity. The continuous treatments with AX (0.1 to 1 mM) from both the prereproductive and young adult stages extended the mean lifespans by about 16–30% in the wild-type and long-lived mutantage-1ofC. elegans. In contrast, the AX-dependent lifespan extension was not observed even in adaf-16null mutant. Especially, the expression of genes encoding superoxide dismutases and catalases increased in two weeks after hatching, and the DAF-16 protein was translocated to the nucleus in the AX-exposed wild type. These results suggest that AX protects the cell organelle mitochondria and nucleus of the nematode, resulting in a lifespan extension via an Ins/IGF-1 signaling pathway during normal aging, at least in part.

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Wnt/β-Catenin and Wnt5a/Ca2+ Pathways Regulate Proliferation and Apoptosis of Keratinocytes in Psoriasis Lesions

Cellular Physiology and Biochemistry ◽

10.1159/000430158 ◽

2015 ◽

Vol 36 (5) ◽

pp. 1890-1902 ◽

Cited By ~ 29

Author(s):

Yanfei Zhang ◽

Chen Tu ◽

Dingwei Zhang ◽

Yan Zheng ◽

Zhenhui Peng ◽

...

Keyword(s):

Human Keratinocytes ◽

Mrna Levels ◽

Protein Levels ◽

Proliferation And Apoptosis ◽

Genes Encoding ◽

Keratinocyte Cell ◽

Normal Human ◽

Induced Apoptosis ◽

Psoriatic Lesions

Background/Aims: Wnt5a is overexpressed in psoriasis lesions, however the mechanism by which Wnt5a is involved in the pathogenesis of psoriasis is not clear. To address this, the expression of Wnt5a in psoriatic lesions and its effect on keratinocyte cell proliferation and apoptosis was examined in vitro. Methods: The expression levels of WNT5A, and genes encoding its receptors frizzled2 (FZD2) and frizzled5 (FZD5) were examined in samples obtained from individuals with psoriasis and healthy controls. Knockdown of Wnt5a with short interfering (si)RNAs was performed in cultured HaCaT keratinocytes and normal human keratinocytes (NHK), and the expression of Wnt5a, protein kinase C (PKC), and β-catenin were determined, and cell cycle activity, proliferation and apoptosis were assessed. Results: The expression of WNT5A, FZD2 and FZD5 mRNA and protein were increased in psoriatic lesions. Wnt5a knockdown suppressed proliferation and induced apoptosis in HaCaT and NHK cells. Additionally, expression of PCNA, MKI67, CCND1, BCL2, CTNNB1, and genes encoding PKC and survivin were downregulated, whereas CASP3 was upregulated. The mRNA levels of the Wnt pathway inhibitors DKK1 and SFRP1 were upregulated, Western blotting analyses demonstrated reduction in β-catenin and PKC protein levels. Conclusion: Knockdown of Wnt5a suppresses the proliferation of keratinocytes and induces apoptosis by inhibiting the Wnt/β-catenin or Wnt5a/Ca2+ pathways.

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