共查询到20条相似文献,搜索用时 33 毫秒
1.
Shuqing Zhang Minrui Xu Jian Huang Lili Tang Yanqing Zhang Jingyao Wu Shuo Lin Han Wang 《Disease models & mechanisms》2014,7(7):837-845
Using a zebrafish model of hepatoerythropoietic porphyria (HEP), we identify a previously unknown mechanism underlying heme-mediated regulation of exocrine zymogens. Zebrafish bach1b, nrf2a and mafK are all expressed in the zebrafish exocrine pancreas. Overexpression of bach1b or knockdown of nrf2a result in the downregulation of the expression of the exocrine zymogens, whereas overexpression of nrf2a or knockdown of bach1b cause their upregulation. In vitro luciferase assays demonstrate that heme activates the zymogens in a dosage-dependent manner and that the zymogen promoter activities require the integral Maf recognition element (MARE) motif. The Bach1b-MafK heterodimer represses the zymogen promoters, whereas the Nrf2a-MafK heterodimer activates them. Furthermore, chromatin immunoprecipitation (ChIP) assays show that MafK binds to the MARE sites in the 5′ regulatory regions of the zymogens. Taken together, these data indicate that heme stimulates the exchange of Bach1b for Nrf2a at MafK-occupied MARE sites and that, particularly in heme-deficient porphyria, the repressive Bach1b-MafK heterodimer dominates, which can be exchanged for the activating Nrf2a-MafK heterodimer upon treatment with hemin. These results provide novel insights into the regulation of exocrine function, as well as the pathogenesis of porphyria, and should be useful for designing new therapies for both types of disease.KEY WORDS: Bach1b, Nrf2a, MafK, Heme, Porphyria, Zymogens, Zebrafish 相似文献
2.
Wang H 《Genetica》2009,136(1):149-161
Bmal1 (Brain and muscle ARNT
like 1) gene is a key circadian clock gene. Tetrapods also have the second Bmal gene, Bmal2. Fruit fly has only one bmal1/cycle gene. Interrogation of the five teleost fish genome sequences coupled with phylogenetic and splice site analyses found that
zebrafish have two bmal1 genes, bmal1a and bmal1b, and bmal2a; Japanese pufferfish (fugu), green spotted pufferfish (tetraodon) and Japanese medaka fish each have two bmal2 genes, bmal2a and bmal2b, and bmal1a; and three-spine stickleback have bmal1a and bmal2b. Syntenic analysis further indicated that zebrafish bmal1a/bmal1b, and fugu, tetraodon and medaka bmal2a/bmal2b are ancient duplicates. Although the dN/dS ratios of these four fish bmal duplicates are all <1, implicating they have been under purifying selection, the Tajima relative rate test showed that fugu,
tetraodon and medaka bmal2a/bmal2b have asymmetric evolutionary rates, suggesting that one of these duplicates have been subject to positive selection or relaxed
functional constraint. These results support the notion that teleost fish bmal genes were derived from the fish-specific genome duplication (FSGD), divergent resolution following the duplication led to
retaining different ancient bmal duplicates in different fishes, which could have shaped the evolution of the complex teleost fish timekeeping mechanisms.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
4.
Bin Cai Xiangxiong Kong Chao Zhong Suli Sun Xiao Feng Zhou Yin Hua Jin Youning Wang Xia Li Zhendong Zhu Jing Bo Jin 《植物学报(英文版)》2017,59(1):2-14
SIZ1 is a small ubiquitin‐related modifier (SUMO) E3 ligase that mediates post‐translational SUMO modification of target proteins and thereby regulates developmental processes and hormonal and environmental stress responses in Arabidopsis. However, the role of SUMO E3 ligases in crop plants is largely unknown. Here, we identified and characterized two Glycine max (soybean) SUMO E3 ligases, GmSIZ1a and GmSIZ1b. Expression of GmSIZ1a and GmSIZ1b was induced in response to salicylic acid (SA), heat, and dehydration treatment, but not in response to cold, abscisic acid (ABA), and NaCl treatment. Although GmSIZ1a was expressed at higher levels than GmSIZ1b, both genes encoded proteins with SUMO E3 ligase activity in vivo. Heterologous expression of GmSIZ1a or GmSIZ1b rescued the mutant phenotype of Arabidopsis siz1‐2, including dwarfism, constitutively activated expression of pathogen‐related genes, and ABA‐sensitive seed germination. Simultaneous downregulation of GmSIZ1a and GmSIZ1b (GmSIZ1a/b) using RNA interference (RNAi)‐mediated gene silencing decreased heat shock‐induced SUMO conjugation in soybean. Moreover, GmSIZ1RNAi plants exhibited reduced plant height and leaf size. However, unlike Arabidopsis siz1‐2 mutant plants, flowering time and SA levels were not significantly altered in GmSIZ1RNAi plants. Taken together, our results indicate that GmSIZ1a and GmSIZ1b mediate SUMO modification and positively regulate vegetative growth in soybean. 相似文献
5.
Plasticity and innovation of regulatory mechanisms underlying seed oil content mediated by duplicated genes in the palaeopolyploid soybean 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《The Plant journal : for cell and molecular biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dajian Zhang Meixia Zhao Shuai Li Lianjun Sun Weidong Wang Chunmei Cai Emily C. Dierking Jianxin Ma 《The Plant journal : for cell and molecular biology》2017,90(6):1120-1133
Many plants have undergone whole genome duplication (WGD). However, how regulatory networks underlying a particular trait are reshaped in polyploids has not been experimentally investigated. Here we show that the regulatory pathways modulating seed oil content, which involve WRINKLED1 (WRI1), LEAFY COTYLEDON1 (LEC1), and LEC2 in Arabidopsis, have been modified in the palaeopolyploid soybean. Such modifications include functional reduction of GmWRI1b of the GmWRI1a/GmWRI1b homoeologous pair relevant to WRI1, complementary non‐allelic dosage effects of the GmLEC1a/GmLEC1b homoeologous pair relevant to LEC1, pseudogenization of the singleton GmLEC2 relevant to LEC2, and the rise of the LEC2‐like function of GmABI3b, contrasting to its homoeolog GmABI3a, which maintains the ABSCISIC ACID INSENSITIVE 3 (ABI3)‐like function in modulating seed maturation and dormancy. The function of GmABI3b in modulating seed oil biosynthesis was fulfilled by direct binding to a RY (CATGCA) cis‐regulatory element in the GmWRI1a promoter, which was absent in the GmWRI1b promoter, resulting in reduction of the GmWRI1b expression. Nevertheless, the three regulators each exhibited similar intensities of purifying selection to their respective duplicates since these pairs were formed by a WGD event that is proposed to have occurred approximately 13 million years ago (mya), suggesting that the differentiation in spatiotemporal expression between the duplicated genes is more likely to be the outcome of neutral variation in regulatory sequences. This study thus exemplifies the plasticity, dynamics, and novelty of regulatory networks mediated by WGD. 相似文献
6.
Metallothioneins (MTs) are cysteine-rich proteins required for heavy metal tolerance in animals and fungi. Recent results indicate that plants also possess functional metallothionein genes. Here we report the cloning and characterization of five metallothionein genes fromArabidopsis thaliana. The position of the single intron in each gene is conserved. The proteins encoded by these genes can be divided into two groups (MT1 and MT2) based on the presence or absence of a central domain separating two cysteine-rich domains. Four of the MT genes (MT1a,MT1c,MT2a andMT2b) are transcribed inArabidopsis. Several lines of evidence suggest that the fifth gene,MT1b, is inactive. There is differential regulation of the MT gene family. MT1 mRNA is expressed highly in roots, moderately in leaves and is barely detected in inflorescences and siliques. MT2a and MT2b mRNAs are more abundant in leaves, inflorescences and in roots from mature plants, but are also detected in roots of young plants, and in siliques. MT2a mRNA is strongly induced in seedlings by CUSO4, whereas MT2b mRNA is relatively abundant in this tissue and levels increase only slightly upon exposure to copper.MT1a andMT1c are located within 2 kb of each other and have been mapped to chromosome 1.MT1b andMT2b map to separate loci on chromosome V, andMT2a is located on chromosome III. The locations of these MT genes are different from that ofCAD1, a gene involved in cadmium tolerance inArabidopsis. 相似文献
7.
Sang‐Hwa Lee Yasuhito Sakuraba Taeyoung Lee Kyu‐Won Kim Gynheung An Han Yong Lee Nam‐Chon Paek 《植物学报(英文版)》2015,57(6):562-576
Jasmonic acid (JA) functions in plant development, including senescence and immunity. Arabidopsis thaliana CORONATINE INSENSITIVE 1 encodes a JA receptor and functions in the JA‐responsive signaling pathway. The Arabidopsis genome harbors a single COI gene, but the rice (Oryza sativa) genome harbors three COI homologs, OsCOI1a, OsCOI1b, and OsCOI2. Thus, it remains unclear whether each OsCOI has distinct, additive, synergistic, or redundant functions in development. Here, we use the oscoi1b‐1 knockout mutants to show that OsCOI1b mainly affects leaf senescence under senescence‐promoting conditions. oscoi1b‐1 mutants stayed green during dark‐induced and natural senescence, with substantial retention of chlorophylls and photosynthetic capacity. Furthermore, several senescence‐associated genes were downregulated in oscoi1b‐1 mutants, including homologs of Arabidopsis thaliana ETHYLENE INSENSITIVE 3 and ORESARA 1, important regulators of leaf senescence. These results suggest that crosstalk between JA signaling and ethylene signaling affects leaf senescence. The Arabidopsis coi1‐1 plants containing 35S:OsCOI1a or 35S:OsCOI1b rescued the delayed leaf senescence during dark incubation, suggesting that both OsCOI1a and OsCOI1b are required for promoting leaf senescence in rice. oscoi1b‐1 mutants showed significant decreases in spikelet fertility and grain weight, leading to severe reduction of grain yield, indicating that OsCOI1‐mediated JA signaling affects spikelet fertility and grain filling. 相似文献
8.
9.
10.
11.
12.
13.
Gare Hoon Yeo Felicia S. H. Cheah Christoph Winkler Ethylin Wang Jabs Byrappa Venkatesh Samuel S. Chong 《Development genes and evolution》2009,219(6):289-300
Four members of the twist gene family (twist1a, 1b, 2, and 3) are found in the zebrafish, and they are thought to have arisen through three rounds of gene duplication, two of which occurred
prior to the tetrapod-fish split. Phylogenetic analysis groups most of the vertebrate Twist1 peptides into clade I, except
for the Twist1b proteins of the acanthopterygian fish (medaka, pufferfish, stickleback), which clustered within clade III.
Paralogies and orthologies among the zebrafish, medaka, and human twist genes were determined using comparative synteny analysis of the chromosomal regions flanking these genes. Comparative nucleotide
substitution analyses also revealed a faster rate of nucleotide mutation/substitution in the acanthopterygian twist1b compared to the zebrafish twist1b, thus accounting for their anomalous phylogenetic clustering. We also observed minimal expression overlap among the four
twist genes, suggesting that despite their significant peptide similarity, their regulatory controls have diverged considerably,
with minimal functional redundancy between them.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
15.
Differential expression of cucumber RNA‐dependent RNA polymerase 1 genes during antiviral defence and resistance
下载免费PDF全文
![点击此处可从《Molecular Plant Pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Diana Leibman Michael Kravchik Dalia Wolf Sabrina Haviv Mira Weissberg Ron Ophir Harry S. Paris Peter Palukaitis Shou‐Wei Ding Victor Gaba Amit Gal‐On 《Molecular Plant Pathology》2018,19(2):300-312
16.
17.
18.
H. Verreycken G. Van Thuyne C. Belpaire 《Zeitschrift fur angewandte Ichthyologie》2011,27(6):1416-1421
Nearly 263 000 individual length–weight (L/W) data, collected during 2839 fish stock assessments between 1992 and 2009, were used to calculate L/W relationships (W = aLb) of 40 freshwater fish species from Flanders (Belgium). Roach Rutilus rutilus, perch Perca fluviatilis, three‐spine stickleback Gasterosteus aculeatus, gudgeon Gobio gobio and European eel Anguilla anguilla were the most abundant species in our surveys. Mean a and b values were in accordance with those available in FishBase. Mean b across all examined species is 3.094 (95% CL = 3.041 to 3.148) indicating a tendency towards slightly positive allometric growth in most fishes (thirty‐three species with b > 3). On the basis of a form factor equation, we characterized 2 species as ‘eel‐like’, 7 as ‘elongated’, 22 as ‘fusiform’ and 9 species as ‘short and deep’. This paper adds a substantial dataset to the yet scarcely available a and b values of European populations of freshwater fish species. 相似文献
19.
Pei Xu Hui Lan Zhu Hai Bin Xu Zheng Zhi Zhang Cai Qin Zhang Li Xia Zhang Zheng Qiang Ma 《Molecular biology reports》2010,37(2):825-832
Cryptochrome (CRY) gene family encodes photoreceptors mediating developmental responses to blue light throughout the life
of plants. We report here the characterization of CRY gene family in hexaploid wheat. Degenerate PCR amplification of the regions encoding the conserved flavin-binding domain
of CRY proteins yielded seven bands, resulting from amplification of CRY1a, CRY1b and CRY2 homologous genes. Assignment of individual amplicons to subgenomes was accomplished by comparing their sequence compositions
with those from the ancestor species of wheat. ESTs coding for CRY-DASH like proteins were identified in wheat EST database
in GenBank. Southern blot showed that TaCRY1a, TaCRY1b and TaCRY2 are single copy genes. We mapped TaCRY1a and TaCRY2 to chromosomes of homoeologous group 6, TaCRY1b to group 2, and TaCRY-DASH to group 7. Phylogenetic analysis showed that CRY subfamily diversification occurred before the divergence of monocots and dicots. The regulatory and functional changes of
CRY members within subfamily are discussed. 相似文献