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1.
Environ Sci Pollut Res Int ; 31(28): 41084-41106, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38842782

ABSTRACT

Current studies do not provide a consensus on whether digital technology innovation can reduce enterprise carbon intensity despite the rise of the digital economy. This paper examines the role and influence pathway of digital technology innovation on enterprise carbon intensity using data from A-share listed enterprises in China's manufacturing industry from 2012 to 2021. The findings indicate that (1) digital technology innovation has been found to significantly reduce enterprise carbon intensity, as confirmed by numerous robustness and endogeneity tests. However, its inhibitory effect on carbon intensity shows a marginal decreasing trend. (2) In the heterogeneity analysis, it was found that digital technology innovation significantly reduces the carbon intensity of consuming coal, coke, kerosene, and diesel. From various perspectives, including enterprise, industry, and external environment, there are significant differences in the carbon reduction effects of digital technology innovation. (3) The analysis of impact paths reveals that digital technology innovation can affect enterprise carbon intensity through three paths: improving productivity, enhancing green innovation efficiency, and adjusting energy consumption. (4) Upon further analysis, it was discovered that the spillover effect of digital technology innovation is more pronounced in the industry cohort of enterprises. Additionally, digital technology innovation plays a positive role in enhancing enterprise ESG performance. The paper's findings offer empirical evidence and decision-making references for the government to develop reasonable policies for reducing carbon emissions, promoting green and low-carbon enterprise transformation, and actively and steadily achieving the goal of carbon peaking and carbon neutrality.


Subject(s)
Carbon , Digital Technology , China , Inventions , Industry
2.
Mol Biol Rep ; 51(1): 556, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38642177

ABSTRACT

BACKGROUND: The Keap1-Nrf2 pathway serves as a central regulator that mediates transcriptional responses to xenobiotic and oxidative stimuli. Recent studies have shown that Keap1 and Nrf2 can regulate transcripts beyond antioxidant and detoxifying genes, yet the underlying mechanisms remain unclear. Our research has uncovered that Drosophila Keap1 (dKeap1) and Nrf2 (CncC) proteins can control high-order chromatin structure, including heterochromatin. METHODS AND RESULTS: In this study, we identified the molecular interaction between dKeap1 and lamin Dm0, the Drosophila B-type lamin responsible for the architecture of nuclear lamina and chromatin. Ectopic expression of dKeap1 led to an ectopic localization of lamin to the intra-nuclear area, corelated with the spreading of the heterochromatin marker H3K9me2 into euchromatin regions. Additionally, mis-regulated dKeap1 disrupted the morphology of the nuclear lamina. Knocking down of dKeap1 partially rescued the lethality induced by lamin overexpression, suggesting their genetic interaction during development. CONCLUSIONS: The discovered dKeap1-lamin interaction suggests a novel role for the Keap1 oxidative/xenobiotic response factor in regulating chromatin architecture.


Subject(s)
Kelch-Like ECH-Associated Protein 1 , Lamins , Nuclear Lamina , Xenobiotics , Animals , Chromatin/metabolism , Drosophila , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Heterochromatin/metabolism , Kelch-Like ECH-Associated Protein 1/genetics , Kelch-Like ECH-Associated Protein 1/metabolism , Lamins/genetics , Lamins/chemistry , Lamins/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Xenobiotics/metabolism , Cell Nucleus/metabolism , Nuclear Lamina/metabolism
3.
Biodivers Data J ; 12: e113979, 2024.
Article in English | MEDLINE | ID: mdl-38348181

ABSTRACT

Asian warty newts, genus Paramesotriton, are endemic to southern China and northern Vietnam. Despite the achievements in biodiversity, molecular systematics and biogeography of species in this genus, population genetic diversity studies are lacking due to the lack of economical and available genetic markers. In this study, we developed 17 highly polymorphic microsatellite loci from RAD simplified genomic data for the Asian warty newts, genus Paramesotriton and successfully completed cross-species amplification tests on 20 samples of four species of Paramesotriton. These microsatellite markers can be used as important tools to study population genetic structure, levels of gene flow, population differentiation, mating systems and landscape genetics within the genus Paramesotriton and, thus, to make scientific conservation decisions and actions for the conservation of these rare and endangered amphibians.

4.
Ecol Evol ; 13(12): e10829, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38145017

ABSTRACT

Asian warty treefrogs, genus Theloderma, are morphologically variable arboreal frogs endemic to Southeast Asia and Southern China. However, integrated systematic studies are lacking, and knowledge of the genus in terms of diversity, origin, and historical diversification remains limited. To address these knowledge gaps, we used three mitochondrial and five nuclear gene fragments to reconstruct the Theloderma phylogeny, estimate divergence times, and examine the biogeography of the genus. Phylogenetic and species delimitation analyses suggest that the genus Theloderma comprises three major clades corresponding to two subgenera and seven species groups, and mPTP identified at least 12 putative cryptic species, suggesting that species diversity has been underestimated. Biogeographic analyses indicated that most recent common ancestor of Theloderma originated in the Indochina Peninsula during the Middle Oligocene (ca. 27.77 Ma) and the splitting of Clade A to C occurred in the Late Oligocene (ca. 23.55-25.57 Ma). Current biogeographic patterns result from two distinct processes: in situ diversification in the Indochina Peninsula and dispersal in multiple areas, namely southward dispersal to the Malay Peninsula and Borneo, northeastward dispersal to Southern China, northward dispersal to the Himalayas, and dispersal from Southern China to the Indochina Peninsula. Ancestral character reconstruction suggests that the ancestor of Theloderma may have possessed a small body size, rough dorsal skin, and absence of vomerine teeth and hand webbing, and that these four characters have undergone multiple evolutions. Principal component analysis based on eight bioclimatic variables did not clearly distinguish the three major clades of Theloderma, suggesting that species in these clades may occupy similar climatic ecological niches. Our research highlights the importance of orogeny and paleoclimatic changes, in shaping amphibian biodiversity in mountain ecosystems.

5.
Zookeys ; 1180: 81-104, 2023.
Article in English | MEDLINE | ID: mdl-37767522

ABSTRACT

In this work, a new species of the genus Oreonectes is described, named Oreonectesdamingshanensis Yu, Luo, Lan, Xiao & Zhou, sp. nov., collected from the Damingshan Mountains of the Guangxi Zhuang Autonomous Region, China. Phylogenetic trees constructed based on the mitochondrial Cyt b showed that the new species represents an independent evolutionary lineage, with uncorrected genetic distances (p-distance) from congeners ranging from 6.1% to 8.9%. Morphologically, the new species can be distinguished from five other species of the genus by a combination of characters. The discovery of this new species raises the number of known species of Oreonectes from five to six. Our study suggests that O.platycephalus may be a complex containing multiple species and that previously recorded areas need to be further delimited and reevaluated.

6.
Cells ; 12(6)2023 03 19.
Article in English | MEDLINE | ID: mdl-36980279

ABSTRACT

Nrf2 is the dominant cellular stress response factor that protects cells through transcriptional responses to xenobiotic and oxidative stimuli. Nrf2 malfunction is highly correlated with many human diseases, but the underlying molecular mechanisms remain to be fully uncovered. GATA4 is a conserved GATA family transcription factor that is essential for cardiac and dorsal epidermal development. Here, we describe a novel interaction between Drosophila Nrf2 and GATA4 proteins, i.e., cap'n'collar C (CncC) and Pannier (Pnr), respectively. Using the bimolecular fluorescence complementation (BiFC) assay-a unique imaging tool for probing protein complexes in living cells-we detected CncC-Pnr complexes in the nuclei of Drosophila embryonic and salivary gland cells. Visualization of CncC-Pnr BiFC signals on the polytene chromosome revealed that CncC and Pnr tend to form complexes in euchromatic regions, with a preference for loci that are not highly occupied by CncC or Pnr alone. Most genes within these loci are activated by the CncC-Pnr BiFC, but not by individually expressed CncC or Pnr fusion proteins, indicating a novel mechanism whereby CncC and Pnr interact at specific genomic loci and coactivate genes at these loci. Finally, CncC-induced early lethality can be rescued by Pnr depletion, suggesting that CncC and Pnr function in the same genetic pathway during the early development of Drosophila. Taken together, these results elucidate a novel crosstalk between the Nrf2 xenobiotic/oxidative response factor and GATA factors in the transcriptional regulation of development. This study also demonstrates that the polytene chromosome BiFC assay is a valuable tool for mapping genes that are targeted by specific transcription factor complexes.


Subject(s)
Drosophila Proteins , Drosophila , GATA4 Transcription Factor , NF-E2-Related Factor 2 , Transcriptional Activation , Animals , Chromatin/genetics , Chromatin/metabolism , Drosophila/genetics , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , GATA4 Transcription Factor/genetics , GATA4 Transcription Factor/metabolism , NF-E2-Related Factor 2/metabolism , Polytene Chromosomes/metabolism , Xenobiotics/metabolism , Transcriptional Activation/genetics
8.
Zool Res ; 43(5): 787-804, 2022 09 18.
Article in English | MEDLINE | ID: mdl-35993131

ABSTRACT

The Paramesotriton Chang, 1935 genus of Asian warty newts is the second most diverse genus in the family Salamandridae, currently containing 14 recognized species from northern Vietnam to southwest-central and southern China. Although species of this genus have been included in previous phylogenetic studies, the origin and interspecific relationships of the genus are still not fully resolved, especially at key nodes in the phylogeny. In this study, we sequenced mitochondrial genomes and 32 nuclear genes from 27 samples belonging to 14 species to reconstruct the interspecific phylogenetic relationships within Paramesotriton and explore its historical biogeography in southern China. Both Bayesian inference and maximum-likelihood analyses highly supported the monophyly of Paramesotriton and its two recognized species groups ( P. caudopunctatus and P. chinensis groups) and further identified five hypothetical phylogenetic cryptic species. Biogeographic analyses indicated that Paramesotriton originated in southwestern China (Yunnan-Guizhou Plateau/South China) during the late Oligocene. The time of origin of Paramesotriton corresponded to the second uplift of the Himalayan/Qinghai-Xizang (Tibetan) Plateau (QTP), rapid lateral extrusion of Indochina, and formation of karst landscapes in southwestern China. Principal component analysis (PCA), independent sample t-tests, and niche differentiation using bioclimatic variables based on locations of occurrence suggested that Paramesotriton habitat conditions in the three current regions (West, South, and East) differ significantly, with different levels of climatic niche differentiation. Species distribution model (SDM) predictions indicated that the most suitable distribution areas for the P. caudopunctatus and P. chinensis species groups are western and southern/eastern areas of southern China. This study increases our knowledge of the taxonomy, biodiversity, origin, and suitable distribution areas of the genus Paramesotriton based on phylogenetic, biogeographic, and species distribution models.


Subject(s)
Genome, Mitochondrial , Animals , Bayes Theorem , China , Phylogeny , Salamandridae/genetics
9.
Dev Biol ; 481: 139-147, 2022 01.
Article in English | MEDLINE | ID: mdl-34662537

ABSTRACT

The Keap1-Nrf2 complex is a central regulator that mediates transcriptional responses to xenobiotic stimuli and is highly related with multiple human diseases. The molecular mechanisms and biological functions of Keap1 and Nrf2 are not fully understood. The Drosophila Keap1 homolog (dKeap1) is conserved with mammalian Keap1 except that dKeap1 contains a 156 aa C-terminal tail (CTD). A dKeap1 truncation with the CTD removed (dKeap1-ΔCTD) shows abolished nuclear localization and chromatin-binding. Expression of dKeap1-ΔCTD in the dKeap1 null background significantly rescues this mutant to the adult stage, but the files showed partial lethality, sterility and defects in adipose tissue. In the rescued flies, expression levels of ecdysone-response genes, ecdysone-synthetic genes and adipogenesis genes were down-regulated in specific tissues, indicating that the chromatin-binding of dKeap1 mediates the activation of these developmental genes. At the same time, dKeap1-ΔCTD can still suppress the basal expression of detoxifying genes and mediate the activation of these genes in response to xenobiotic stimuli, suggesting that the chromatin-binding of dKeap1 is not required for the regulation of detoxifying genes. These results support a model in which dKeap1 on one hand functions as an inhibitor for the Nrf2-mediated transcription in the xenobiotic response pathway and on the other hand functions as a chromatin-binding transcription activator in the developmental pathway. Our study reveals a novel mechanism whereby Keap1-Nrf2 xenobiotic response signaling regulates development using a mechanism independent of redox signaling.


Subject(s)
Chromatin , Drosophila Proteins , Gene Expression Regulation, Developmental , Kelch-Like ECH-Associated Protein 1 , Models, Biological , Transcription, Genetic , Xenobiotics , Animals , Chromatin/genetics , Chromatin/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster , Kelch-Like ECH-Associated Protein 1/genetics , Kelch-Like ECH-Associated Protein 1/metabolism
10.
Orthop Surg ; 12(3): 761-769, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32351029

ABSTRACT

OBJECTIVE: To investigate the incidence of cervical anomalies (CA), including cervical intraspinal neural axis abnormalities (CIINAA) and/or cervical osseous abnormalities (COA), and the clinical relevance in severe spinal deformities (SSD) at a single center. METHODS: A retrospective study of SSD admitted for spinal surgery from January 2003 to January 2015 was conducted at a single center. INCLUSION CRITERIA: patients who present with coronal Cobb over 90° (and/or sagittal cobb ≥90°); and patients with complete imaging and clinical data preoperatively. EXCLUSION CRITERIA: ankylosing spondylitis, adult onset scoliosis, scoliosis secondary to bone destruction. There were 108 SSD patients who fulfilled the criteria in this research (41 males and 67 females). The mean age of the patients was 18.1 ± 2.7 years (range, 10-45 years). The clinical and radiological data of these patients were reviewed to identify CA and to analyze the relationship between clinical and radiographic characteristics in the population of SSD. RESULTS: The major curves of scoliosis and segmental kyphosis were 109.1° ± 24.7° and 91.2° ± 29.1°. Cervical abnormalities were detected in 56 patients (51.85%) with 9 different CA, including 28 patients (25.9%) with 6 different COA, 21 patients (19.4%) with 3 different CIINAA, and 7 patients (6.5%) with a combination of COA and cervical intraspinal neural axis abnormalities (CINAA). Basilar invagination and Klippel-Feil syndrome were the most frequent COA. Syringomyelia was the most frequent CINAA. SSD with COA in upper vertebral levels (UVL) had a higher incidence of CINAA than those in subaxial vertebral levels (SVL) (P = 0.024) and SSD with multiple COA (mCOA) in UVL had a higher incidence of CINAA than those with single COA (sCOA) (P = 0.029). In the present study, 83.9% of the SSD with CA were asymptomatic. CONCLUSION: The incidence of CA in SSD was 51.85%, with most presenting with intact neurologic status. As the diversity of COA increased, we found a higher incidence of CINAA, especially in UVL.


Subject(s)
Cervical Vertebrae/abnormalities , Cervical Vertebrae/diagnostic imaging , Nervous System Malformations/diagnostic imaging , Spinal Cord Diseases/diagnostic imaging , Spinal Diseases/diagnostic imaging , Adolescent , Adult , Child , Female , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Young Adult
11.
Genesis ; 57(4): e23290, 2019 04.
Article in English | MEDLINE | ID: mdl-30888733

ABSTRACT

The Keap1-Nrf2 signaling pathway plays a central role in the regulation of transcriptional responses to oxidative species and xenobiotic stimuli. The complete range of molecular mechanisms and biological functions of Keap1 and Nrf2 remain to be fully elucidated. To determine the potential roles of Keap1 and Nrf2 in chromatin architecture, we examined the effects of their Drosophila homologs (dKeap1 and CncC) on position effect variegation (PEV), which is a transcriptional reporter for heterochromatin formation and spreading. Loss of function mutations in cncC, dKeap1, and cncC/dKeap1 double mutants all suppressed the variegation of wm4 and SbV PEV alleles, indicating that reduction of CncC or dKeap1 causes a decrease of heterochromatic silencing at pericentric region. Depletion of CncC or dKeap1 in embryos reduced the level of the H3K9me2 heterochromatin marker, but had no effect on the transcription of the genes encoding Su(var)3-9 and HP1. These results support a potential role of dKeap1 and CncC in the establishment and/or maintenance of pericentric heterochromatin. Our study provides preliminary evidence for a novel epigenetic function of Keap1-Nrf2 oxidative/xenobiotic response factors in chromatin remodeling.


Subject(s)
Chromosomal Position Effects , Drosophila Proteins/metabolism , Heterochromatin/genetics , Kelch-Like ECH-Associated Protein 1/metabolism , NF-E2-Related Factor 2/metabolism , Animals , Drosophila Proteins/genetics , Drosophila melanogaster , Epigenesis, Genetic , Heterochromatin/metabolism , Kelch-Like ECH-Associated Protein 1/genetics , NF-E2-Related Factor 2/genetics , Repressor Proteins/genetics , Repressor Proteins/metabolism
12.
Development ; 144(18): 3232-3240, 2017 09 15.
Article in English | MEDLINE | ID: mdl-28807902

ABSTRACT

A model has been proposed in which JIL-1 kinase-mediated H3S10 and H2Av phosphorylation is required for transcriptional elongation and heat shock-induced chromatin decondensation. However, here we show that although H3S10 phosphorylation is indeed compromised in the H2Av null mutant, chromatin decondensation at heat shock loci is unaffected in the absence of JIL-1 as well as of H2Av and that there is no discernable decrease in the elongating form of RNA polymerase II in either mutant. Furthermore, mRNA for the major heat shock protein Hsp70 is transcribed at robust levels in both H2Av and JIL-1 null mutants. Using a different chromatin remodeling paradigm that is JIL-1 dependent, we provide evidence that ectopic tethering of JIL-1 and subsequent H3S10 phosphorylation recruits PARP-1 to the remodeling site independently of H2Av phosphorylation. These data strongly suggest that H2Av or H3S10 phosphorylation by JIL-1 is not required for chromatin decondensation or transcriptional elongation in Drosophila.


Subject(s)
Chromatin/metabolism , Drosophila Proteins/metabolism , Drosophila melanogaster/metabolism , Histones/metabolism , Phosphoserine/metabolism , Transcription Elongation, Genetic , Animals , Euchromatin/metabolism , Green Fluorescent Proteins/metabolism , Heat-Shock Response/genetics , Immunoblotting , Immunohistochemistry , Lac Operon/genetics , Mutation/genetics , Phosphorylation , Poly(ADP-ribose) Polymerases/metabolism , Polytene Chromosomes/metabolism , Protein Serine-Threonine Kinases/metabolism , Transgenes
13.
Methods Enzymol ; 589: 429-455, 2017.
Article in English | MEDLINE | ID: mdl-28336073

ABSTRACT

We have developed a procedure that enables visualization of the genomic loci that are bound by complexes formed by a specific combination of chromatin-binding proteins. This procedure is based on imaging bimolecular fluorescence complementation (BiFC) complexes on Drosophila polytene chromosomes. BiFC complexes are formed by the facilitated association of two fluorescent protein fragments that are fused to proteins that interact with, or are in close proximity to, each other. The intensity of BiFC complex fluorescence at individual genomic loci is greatly enhanced by the parallel alignment of hundreds of chromatids within the polytene chromosomes. The loci that are bound by the complexes are mapped by comparing the locations of BiFC complex fluorescence with the stereotypical banding patterns of the chromosomes. We describe strategies for the design, expression, and validation of fusion proteins for the analysis of BiFC complex binding on polytene chromosomes. We detail protocols for the preparation of polytene chromosome spreads that have been optimized for the purpose of BiFC complex visualization. Finally, we provide guidance for the interpretation of results from studies of BiFC complex binding on polytene chromosomes and for comparison of the genomic loci that are bound by BiFC complexes with those that are bound by subunits of the corresponding endogenous complexes. The visualization of BiFC complex binding on polytene chromosomes provides a unique method to visualize multiprotein complex binding at specific loci, throughout the genome, in individual cells.


Subject(s)
Drosophila Proteins/metabolism , Drosophila/cytology , Genetic Loci , Multiprotein Complexes/metabolism , Optical Imaging/methods , Polytene Chromosomes/metabolism , Animals , Drosophila/genetics , Drosophila/metabolism , Drosophila Proteins/analysis , Luminescent Proteins/analysis , Luminescent Proteins/metabolism , Microscopy, Fluorescence/methods , Multiprotein Complexes/analysis , Polytene Chromosomes/ultrastructure , Recombinant Fusion Proteins/analysis , Recombinant Fusion Proteins/metabolism
14.
Development ; 141(16): 3277-88, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25063457

ABSTRACT

Interactions among transcription factors control their physiological functions by regulating their binding specificities and transcriptional activities. We implement a strategy to visualize directly the genomic loci that are bound by multi-protein complexes in single cells in Drosophila. This method is based on bimolecular fluorescence complementation (BiFC) analysis of protein interactions on polytene chromosomes. Drosophila Keap1 (dKeap1)-CncC complexes localized to the nucleus and bound chromatin loci that were not bound preferentially by dKeap1 or CncC when they were expressed separately. dKeap1 and CncC binding at these loci was enhanced by phenobarbital, but not by tert-butylhydroquinone (tBHQ) or paraquat. Endogenous dKeap1 and CncC activated transcription of the Jheh (Jheh1, Jheh2, Jheh3) and dKeap1 genes at these loci, whereas CncC alone activated other xenobiotic response genes. Ectopic dKeap1 expression increased CncC binding at the Jheh and dKeap1 gene loci and activated their transcription, whereas dKeap1 inhibited CncC binding at other xenobiotic response gene loci and suppressed their transcription. The combinatorial chromatin-binding specificities and transcriptional activities of dKeap1-CncC complexes mediated the selective activation of different sets of genes by different xenobiotic compounds, in part through feed-forward activation of dKeap1 transcription.


Subject(s)
Chromatin/chemistry , Drosophila Proteins/genetics , Gene Expression Regulation, Developmental/drug effects , Intracellular Signaling Peptides and Proteins/genetics , Transcription Factors/genetics , Animals , Base Sequence , Cell Nucleus/metabolism , Chromosomes/ultrastructure , Drosophila Proteins/metabolism , Drosophila melanogaster , Fluorescent Dyes/chemistry , Hydroquinones/chemistry , Intracellular Signaling Peptides and Proteins/metabolism , Kelch-Like ECH-Associated Protein 1 , Molecular Sequence Data , Paraquat/chemistry , Phenobarbital/chemistry , Protein Binding , Protein Structure, Tertiary , Repressor Proteins , Salivary Glands/embryology , Transcription Factors/metabolism , Transcription, Genetic/drug effects , Xenobiotics
15.
Fly (Austin) ; 8(1): 7-12, 2014.
Article in English | MEDLINE | ID: mdl-24406335

ABSTRACT

Xenobiotic and oxidative responses protect cells from external and internal toxicities. Nrf2 and Keap1 are central factors that mediate these responses, and are closely related with many human diseases. In a recent study, we revealed novel developmental function and regulatory mechanism of Nrf2 and Keap1 by investigating their Drosophila homolog CncC and dKeap1. We found that CncC and dKeap1 control metamorphosis through regulations of ecdysone biosynthetic genes and ecdysone response genes in different tissues. CncC and dKeap1 cooperatively activate these developmental genes, in contrast to their conserved antagonizing effect to xenobiotic response transcription. In addition, interactions between CncC and Ras signaling in metamorphosis and in transcriptional regulation were established. Here I discuss the implications that place these classic xenobiotic response factors into a broader network that potentially control development and oncogenesis using mechanisms other than those mediating xenobiotic response.


Subject(s)
Drosophila Proteins/metabolism , Drosophila/metabolism , Gene Expression Regulation, Developmental , Intracellular Signaling Peptides and Proteins/metabolism , Repressor Proteins/metabolism , Xenobiotics/pharmacology , Animals , Chromatin/metabolism , Drosophila/drug effects , Drosophila/growth & development , Ecdysone/metabolism , Kelch-Like ECH-Associated Protein 1 , Metamorphosis, Biological , NF-E2-Related Factor 2/metabolism , Neoplasms/metabolism , Signal Transduction , ras Proteins/metabolism
16.
J Biol Chem ; 288(27): 19441-9, 2013 Jul 05.
Article in English | MEDLINE | ID: mdl-23723094

ABSTRACT

The JIL-1 kinase localizes to Drosophila polytene chromosome interbands and phosphorylates histone H3 at interphase, counteracting histone H3 lysine 9 dimethylation and gene silencing. JIL-1 can be divided into four main domains, including an NH2-terminal domain, two separate kinase domains, and a COOH-terminal domain. In this study, we characterize the domain requirements of the JIL-1 kinase for histone H3 serine 10 (H3S10) phosphorylation and chromatin remodeling in vivo. We show that a JIL-1 construct without the NH2-terminal domain is without H3S10 phosphorylation activity despite the fact that it localizes properly to polytene interband regions and that it contains both kinase domains. JIL-1 is a double kinase, and we demonstrate that both kinase domains of JIL-1 are required to be catalytically active for H3S10 phosphorylation to occur. Furthermore, we provide evidence that JIL-1 is phosphorylated at serine 424 and that this phosphorylation is necessary for JIL-1 H3S10 phosphorylation activity. Thus, these data are compatible with a model where the NH2-terminal domain of JIL-1 is required for chromatin complex interactions that position the kinase domain(s) for catalytic activity in the context of the state of higher order nucleosome packaging and chromatin structure and where catalytic H3S10 phosphorylation activity mediated by the first kinase domain is dependent on autophosphorylation of serine 424 by the second kinase domain. Furthermore, using a lacO repeat tethering system to target mutated JIL-1 constructs with or without catalytic activity, we show that the epigenetic H3S10 phosphorylation mark itself functions as a causative regulator of chromatin structure independently of any structural contributions from the JIL-1 protein.


Subject(s)
Chromatin Assembly and Disassembly/physiology , Chromatin/metabolism , Drosophila Proteins/metabolism , Epigenesis, Genetic/physiology , Histones/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Chromatin/genetics , Drosophila Proteins/genetics , Drosophila melanogaster , Histones/genetics , Mutation , Phosphorylation/physiology , Polytene Chromosomes/genetics , Polytene Chromosomes/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Structure, Tertiary , Serine/genetics , Serine/metabolism
17.
PLoS Genet ; 9(2): e1003263, 2013.
Article in English | MEDLINE | ID: mdl-23408904

ABSTRACT

Mammalian Nrf2-Keap1 and the homologous Drosophila CncC-dKeap1 protein complexes regulate both transcriptional responses to xenobiotic compounds as well as native cellular and developmental processes. The relationships between the functions of these proteins in xenobiotic responses and in development were unknown. We investigated the genes regulated by CncC and dKeap1 during development and the signal transduction pathways that modulate their functions. CncC and dKeap1 were enriched within the nuclei in many tissues, in contrast to the reported cytoplasmic localization of Keap1 and Nrf2 in cultured mammalian cells. CncC and dKeap1 occupied ecdysone-regulated early puffs on polytene chromosomes. Depletion of either CncC or dKeap1 in salivary glands selectively reduced early puff gene transcription. CncC and dKeap1 depletion in the prothoracic gland as well as cncC(K6/K6) and dKeap1(EY5/EY5) loss of function mutations in embryos reduced ecdysone-biosynthetic gene transcription. In contrast, dKeap1 depletion and the dKeap1(EY5/EY5) loss of function mutation enhanced xenobiotic response gene transcription in larvae and embryos, respectively. Depletion of CncC or dKeap1 in the prothoracic gland delayed pupation by decreasing larval ecdysteroid levels. CncC depletion suppressed the premature pupation and developmental arrest caused by constitutive Ras signaling in the prothoracic gland; conversely, constitutive Ras signaling altered the loci occupied by CncC on polytene chromosomes and activated transcription of genes at these loci. The effects of CncC and dKeap1 on both ecdysone-biosynthetic and ecdysone-regulated gene transcription, and the roles of CncC in Ras signaling in the prothoracic gland, establish the functions of these proteins in the neuroendocrine axis that coordinates insect metamorphosis.


Subject(s)
Drosophila Proteins/genetics , Drosophila melanogaster , Ecdysone , Intracellular Signaling Peptides and Proteins , Metamorphosis, Biological , Transcription Factors/genetics , Xenobiotics/pharmacology , Animals , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/growth & development , Ecdysone/biosynthesis , Ecdysone/metabolism , Gene Expression Regulation, Developmental , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Kelch-Like ECH-Associated Protein 1 , Larva/genetics , Larva/growth & development , Metamorphosis, Biological/drug effects , Metamorphosis, Biological/genetics , Mutation , Polytene Chromosomes/drug effects , Polytene Chromosomes/genetics , Repressor Proteins , Salivary Glands/cytology , Salivary Glands/drug effects , Signal Transduction/genetics , Transcriptional Activation/drug effects
18.
J Cell Sci ; 124(Pt 24): 4309-17, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-22247192

ABSTRACT

The JIL-1 kinase localizes specifically to euchromatin interband regions of polytene chromosomes and is the kinase responsible for histone H3S10 phosphorylation at interphase. Genetic interaction assays with strong JIL-1 hypomorphic loss-of-function alleles have demonstrated that the JIL-1 protein can counterbalance the effect of the major heterochromatin components on position-effect variegation (PEV) and gene silencing. However, it is unclear whether this was a causative effect of the epigenetic H3S10 phosphorylation mark, or whether the effect of the JIL-1 protein on PEV was in fact caused by other functions or structural features of the protein. By transgenically expressing various truncated versions of JIL-1, with or without kinase activity, and assessing their effect on PEV and heterochromatic spreading, we show that the gross perturbation of polytene chromosome morphology observed in JIL-1 null mutants is unrelated to gene silencing in PEV and is likely to occur as a result of faulty polytene chromosome alignment and/or organization, separate from epigenetic regulation of chromatin structure. Furthermore, the findings provide evidence that the epigenetic H3S10 phosphorylation mark itself is necessary for preventing the observed heterochromatic spreading independently of any structural contributions from the JIL-1 protein.


Subject(s)
Chromosomal Position Effects , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Epigenesis, Genetic , Gene Silencing , Protein Serine-Threonine Kinases/genetics , Animals , Drosophila Proteins/metabolism , Drosophila melanogaster/anatomy & histology , Drosophila melanogaster/metabolism , Eye/anatomy & histology , Heterochromatin/metabolism , Histones/metabolism , Phosphorylation , Protein Serine-Threonine Kinases/metabolism , Protein Structure, Tertiary , Transgenes
19.
Chin J Cancer ; 29(7): 703-8, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20591224

ABSTRACT

BACKGROUND AND OBJECTIVE: Elastofibroma dorsi has an extremely low incidence. At present, comparative study on imaging manifestations and pathologic findings of elastofibroma dorsi has not been reported in China. This study was to investigate clinical manifestations, computed tomography (CT) and magnetic resonance imaging (MRI) appearances, and pathologic features of elastofibroma dorsi and to improve preoperative imaging diagnosis of this disease. METHODS: The clinical manifestations, imaging findings, and pathologic appearances of 6 cases of elastofibroma dorsi were retrospectively analyzed and related literatures were reviewed. All patients were examined with MRI, and 4 of them were examined with CT scan. RESULTS: All patients were above 30 years old without obvious symptoms. The tumors presented as a lenticular soft-tissue mass in the deep subscapular region. The tumor's density on plain CT scan or signal intensity on MR T1-weighted image was approximately equal to that of muscle with some interlaced fat-like areas within mass suppressed by fat-suppression MR sequences, which corresponded to dense collagen tissue and interspersed mature adipose tissue observed microscopically. CONCLUSIONS: CT and MRI can reflect the histological features of elastofibroma dorsi. On the basis of their imaging characteristics, a correct preoperative diagnosis of elastofibroma dorsi can easily be made.


Subject(s)
Fibroma/diagnosis , Fibroma/pathology , Soft Tissue Neoplasms/diagnosis , Soft Tissue Neoplasms/pathology , Adult , Aged , Female , Fibroma/diagnostic imaging , Fibroma/surgery , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Scapula/diagnostic imaging , Scapula/pathology , Soft Tissue Neoplasms/diagnostic imaging , Soft Tissue Neoplasms/surgery , Tomography, X-Ray Computed
20.
Genetics ; 185(4): 1183-92, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20457875

ABSTRACT

The essential JIL-1 histone H3S10 kinase is a key regulator of chromatin structure that functions to maintain euchromatic domains while counteracting heterochromatization and gene silencing. In the absence of the JIL-1 kinase, two of the major heterochromatin markers H3K9me2 and HP1a spread in tandem to ectopic locations on the chromosome arms. Here we address the role of the third major heterochromatin component, the zinc-finger protein Su(var)3-7. We show that the lethality but not the chromosome morphology defects associated with the null JIL-1 phenotype to a large degree can be rescued by reducing the dose of the Su(var)3-7 gene and that Su(var)3-7 and JIL-1 loss-of-function mutations have an antagonistic and counterbalancing effect on position-effect variegation (PEV). Furthermore, we show that in the absence of JIL-1 kinase activity, Su(var)3-7 gets redistributed and upregulated on the chromosome arms. Reducing the dose of the Su(var)3-7 gene dramatically decreases this redistribution; however, the spreading of H3K9me2 to the chromosome arms was unaffected, strongly indicating that ectopic Su(var)3-9 activity is not a direct cause of lethality. These observations suggest a model where Su(var)3-7 functions as an effector downstream of Su(var)3-9 and H3K9 dimethylation in heterochromatic spreading and gene silencing that is normally counteracted by JIL-1 kinase activity.


Subject(s)
Chromosomal Position Effects , DNA-Binding Proteins/genetics , Drosophila Proteins/genetics , Epistasis, Genetic , Protein Serine-Threonine Kinases/genetics , Animals , Animals, Genetically Modified , Chromosomes, Insect/genetics , DNA-Binding Proteins/metabolism , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Female , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Histones/metabolism , Immunohistochemistry , Lysine/metabolism , Male , Methylation , Methyltransferases/genetics , Microscopy, Fluorescence , Mutation , Protein Serine-Threonine Kinases/metabolism
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