Ectopic expression of LhMYC2 increases susceptibility to Botrytis cinerea in Arabidopsis thaliana

Canadian Journal of Plant Science ◽

10.1139/cjps-2020-0047 ◽

2020 ◽

Author(s):

Qi Cui ◽

Xue Gao ◽

Lianjuan Wang ◽

Guixia Jia

Keyword(s):

Functional Characterization ◽

Ectopic Expression ◽

Defense Responses ◽

Gray Mold ◽

Wild Type ◽

Transcriptional Changes ◽

Negative Role ◽

Ja Signaling ◽

Fungal Inoculation

Gray mold disease, mainly caused by Botrytis elliptica and B. cinerea, leads to severe losses in lily cut flower and bulb production. MYC2 is a critical regulator of the activation of jasmonate (JA)-mediated defense responses in plants. However, information about the lily MYC2 gene is limited. Therefore, functional characterization of MYC2 in lily, especially its role in plant immune responses, should be performed. Here, significant differences between the Botrytis-resistant Lilium hybrid ‘Sorbonne’ and the Botrytis-susceptible ‘Tresor’ were found following B. cinerea inoculation, as indicated by jasmonic acid (JA) and JA-isoleucine (JA-Ile) accumulation and related gene expression. More JA and JA-Ile were detected in ‘Sorbonne’ than in ‘Tresor’ following fungal inoculation, and higher transcript levels of JA biosynthesis genes (LhAOS, LhAOC, and LhOPR3) and a signaling gene (LhCOI1) were detected in ‘Sorbonne’ than in ‘Tresor’. In contrast, expression of the critical signaling regulator LhMYC2 was higher in ‘Tresor’ than in ‘Sorbonne’. LhMYC2 was then isolated from ‘Sorbonne’ and found to be similar to several plant MYC2 homologs that have pivotal roles in JA signaling. The expression of LhMYC2 increased significantly in response to JA and salicylic acid (SA) in ‘Sorbonne’. Ectopic expression of LhMYC2 in Arabidopsis resulted in greater susceptibility to B. cinerea than that observed in wild-type plants. This susceptibility was coupled with the transcriptional changes in SA- and JA-responsive genes. Overall, our findings indicate that LhMYC2 plays a negative role in Arabidopsis resistance to B. cinerea.

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Functional characterization of the H+/K+ ATPase in wild type and gastrin knock-out mice

Zeitschrift für Gastroenterologie ◽

10.1055/s-2007-982721 ◽

2007 ◽

Vol 45 (05) ◽

Author(s):

A Schnur ◽

P Hegyi ◽

V Venglovecz ◽

Z Rakonczay ◽

I Ignáth ◽

...

Keyword(s):

Functional Characterization ◽

Wild Type ◽

Knock Out ◽

Knock Out Mice

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A Phytophthora capsici RXLR effector manipulates plant immunity by targeting RAB proteins and disturbing vesicle-mediated protein trafficking pathway

10.22541/au.163697880.04261552/v1 ◽

2021 ◽

Author(s):

Tianli Li ◽

Gan Ai ◽

Xiaowei Fu ◽

Jin Liu ◽

Hai Zhu ◽

...

Keyword(s):

Membrane Trafficking ◽

Plant Immunity ◽

Phytophthora Capsici ◽

Functional Characterization ◽

Ectopic Expression ◽

Defense Responses ◽

Infection Process ◽

Small Gtpase ◽

Rab Proteins ◽

Rxlr Effector

The oomycete pathogen Phytophthora capsici encodes hundreds of RXLR effectors to enter plant cells and suppress host defense responses. Only few of them are conserved across different strains and species. Such ‘core effectors’ may target hub immunity pathways that are essential during Phytophthora pathogens interacting with their hosts. However, the underlying mechanisms of core RXLRs-mediated host immunity manipulation are largely unknown. Here, we report the functional characterization of a P. capsici RXLR effector, RXLR242. RXLR242 expression is highly induced during the infection process. Its ectopic expression in Nicotiana benthamiana promotes Phytophthora infection. RXLR242 physically interacts with a group of RAB proteins, which belong to the small GTPase family and function in specifying transport pathways in the intracellular membrane trafficking system. RXLR242 impedes the secretion of PATHOGENESIS-RELATED 1 (PR1) protein to the apoplast by interfering the formation of RABE1-7-labeled vesicles. Further analysis indicated that such phenomenon is resulted from competitive binding of RXLR242 to RABE1-7. RXLR242 also interferes trafficking of the membrane-located receptor FLAGELLIN-SENSING 2 (FLS2) through competitively interacting with RABA4-3. Taken together, our work demonstrates that RXLR242 manipulates plant immunity by targeting RAB proteins and disturbing vesicle-mediated protein transporting pathway in plant hosts.

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Molecular Characterization of the Interaction of Borrelia parkeri and Borrelia turicatae with Human Complement Regulators

Infection and Immunity ◽

10.1128/iai.00089-10 ◽

2010 ◽

Vol 78 (5) ◽

pp. 2199-2208 ◽

Cited By ~ 16

Author(s):

Melanie Schott ◽

Sonja Grosskinsky ◽

Christiane Brenner ◽

Peter Kraiczy ◽

Reinhard Wallich

Keyword(s):

Binding Capacity ◽

Functional Characterization ◽

Ectopic Expression ◽

Factor H ◽

Human Complement ◽

Related Protein ◽

Relapsing Fever ◽

Extracellular Matrix Components ◽

Complement Regulators

ABSTRACT In North America, tick-borne relapsing fever is caused by the species Borrelia hermsii, B. parkeri, and B. turicatae, which are transmitted to humans through the bite of the respective infected tick vectors. Here we describe the identification and functional characterization of a surface lipoprotein of B. parkeri, designated BpcA, that binds the human complement regulators factor H and factor H-related protein 1 and, simultaneously, the host protease plasminogen. In contrast, the homologous B. turicatae protein failed to bind human factor H and factor H-related protein 1 but retained its plasminogen binding capacity. Factor H bound to BpcA maintains its regulatory capacity to control C3b deposition and C3 convertase activity. Ectopic expression of BpcA in a serum-sensitive B. burgdorferi strain protects transformed cells from complement-mediated killing. Furthermore, bound plasminogen/plasmin endows B. parkeri and B. turicatae with the potential to degrade extracellular matrix components. These findings expand our understanding of the putative recent evolutionary separation of Borrelia parkeri and Borrelia turicatae, provide evidence that B. parkeri differs from B. turicatae in its ability to resist complement attack, and may help in understanding the pathological processes underlying tick-borne relapsing fever.

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Functional characterization of the rod visual pigment of the echidna (Tachyglossus aculeatus), a basal mammal

Visual Neuroscience ◽

10.1017/s0952523812000223 ◽

2012 ◽

Vol 29 (4-5) ◽

pp. 211-217 ◽

Cited By ~ 18

Author(s):

CONSTANZE BICKELMANN ◽

JAMES M. MORROW ◽

JOHANNES MÜLLER ◽

BELINDA S.W. CHANG

Keyword(s):

Half Life ◽

Functional Characterization ◽

Egg Laying ◽

Sensory Transduction ◽

Wild Type ◽

Functional Variation ◽

Bovine Rhodopsin ◽

Tachyglossus Aculeatus

AbstractMonotremes are the most basal egg-laying mammals comprised of two extant genera, which are largely nocturnal. Visual pigments, the first step in the sensory transduction cascade in photoreceptors of the eye, have been examined in a variety of vertebrates, but little work has been done to study the rhodopsin of monotremes. We isolated the rhodopsin gene of the nocturnal short-beaked echidna (Tachyglossus aculeatus) and expressed and functionally characterized the protein in vitro. Three mutants were also expressed and characterized: N83D, an important site for spectral tuning and metarhodopsin kinetics, and two sites with amino acids unique to the echidna (T158A and F169A). The λmax of echidna rhodopsin (497.9 ± 1.1 nm) did not vary significantly in either T158A (498.0 ± 1.3 nm) or F169A (499.4 ± 0.1 nm) but was redshifted in N83D (503.8 ± 1.5 nm). Unlike other mammalian rhodopsins, echidna rhodopsin did react when exposed to hydroxylamine, although not as fast as cone opsins. The retinal release rate of light-activated echidna rhodopsin, as measured by fluorescence spectroscopy, had a half-life of 9.5 ± 2.6 min−1, which is significantly shorter than that of bovine rhodopsin. The half-life of the N83D mutant was 5.1 ± 0.1 min−1, even shorter than wild type. Our results show that with respect to hydroxylamine sensitivity and retinal release, the wild-type echidna rhodopsin displays major differences to all previously characterized mammalian rhodopsins and appears more similar to other nonmammalian vertebrate rhodopsins such as chicken and anole. However, our N83D mutagenesis results suggest that this site may mediate adaptation in the echidna to dim light environments, possibly via increased stability of light-activated intermediates. This study is the first characterization of a rhodopsin from a most basal mammal and indicates that there might be more functional variation in mammalian rhodopsins than previously assumed.

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Functional characterization of wild-type and mutant human sialin

The EMBO Journal ◽

10.1038/sj.emboj.7600464 ◽

2004 ◽

Vol 23 (23) ◽

pp. 4560-4570 ◽

Cited By ~ 62

Author(s):

Pierre Morin ◽

Corinne Sagné ◽

Bruno Gasnier

Keyword(s):

Functional Characterization ◽

Wild Type

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Genome-Wide Identification and Analysis of VQ Motif-containing Gene Family in Brassica napus and Functional Characterization of BnMKS1 in Response to Leptosphaeria maculans

Phytopathology ◽

10.1094/phyto-04-20-0134-r ◽

2020 ◽

Cited By ~ 1

Author(s):

Zhongwei Zou ◽

Fei Liu ◽

Shuanglong Huang ◽

DILANTHA GERARD FERNANDO

Keyword(s):

Brassica Napus ◽

Gene Family ◽

Functional Characterization ◽

Leptosphaeria Maculans ◽

Defense Responses ◽

Marker Genes ◽

Blackleg Disease ◽

Genome Wide ◽

A Genome

Proteins containing Valine-glutamine (VQ) motifs play important roles in plant growth and development, as well as in defense responses to both abiotic and biotic stresses. Blackleg disease, which is caused by Leptosphaeria maculans, is the most important disease in canola (Brassica napus L.) worldwide. H; however, the identification of B. napus VQs and their functions in response to blackleg disease have not yet been reported. In this study, we conducted a genome genome-wide identification and characterization of the VQ gene family in B. napus, including chromosome location, phylogenetic relations, gene structure, motif domain, synteny analysis, and cis-elements categorization of their promoter regions. To understand B. napus VQ gene function in response to blackleg disease, we overexpressed BnVQ7 (BnaA01g36880D, also known as the mitogen-activated protein kinase4 substrate1 (MKS1) gene) in a blackleg-susceptible canola variety Westar. Overexpression The overexpression of BnMKS1 in canola did not improve its resistance to blackleg disease at the seedling stage. H; however, transgenic canola plants overexpressing BnMKS1 displayed an enhanced resistance to L. maculans infection at the adult plant stage. Expression levels of downstream and defense marker genes in cotyledons increased significantly at the necrotrophic stage of L. maculans infection in the overexpression line of BnMKS1, suggesting that the SA salicylic acid (SA)- and jasmonic acid (JA )-mediated signaling pathways were both involved in the defense responses. Together, these results suggest that BnMKS1 might play an important role in the defense against L. maculans.

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2066 Functional characterization of mutant BRCA1

Journal of Clinical and Translational Science ◽

10.1017/cts.2018.77 ◽

2018 ◽

Vol 2 (S1) ◽

pp. 13-13

Author(s):

John Barrows ◽

David Long

Keyword(s):

Functional Characterization ◽

Coiled Coil ◽

Wild Type ◽

Coiled Coil Region ◽

Egg Extracts ◽

Study Population ◽

Xenopus Egg ◽

Xenopus Egg Extracts

OBJECTIVES/SPECIFIC AIMS: The objective of this work is to determine the mechanistic consequences of BRCA1 mutants in inter-strand crosslink (ICL) repair. METHODS/STUDY POPULATION: Our lab uses Xenopus egg extracts to study ICL repair. These extracts can be depleted of endogenous BRCA1 by immunoprecipitation. The goal of this work is to rescue endogenous depletion with in vitro translated, wild type BRCA1. Once achieved, we can supplement the depleted extract with BRCA1 mutants to access their function in ICL repair. RESULTS/ANTICIPATED RESULTS: We hypothesize that the BRCT and RING domain mutations will abrogate ICL repair, while mutations in the coiled coil region will not affect repair. DISCUSSION/SIGNIFICANCE OF IMPACT: These findings will have an immense impact on the understanding of BRCA1 domains. Importantly these results will spur personalized therapy of BRCA1 mutants by showing which domains are sensitive to cross-linking agents.

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Functional Characterization of BRASSINAZOLE-RESISTANT 1 in Panax Ginseng (PgBZR1) and Brassinosteroid Response during Storage Root Formation

International Journal of Molecular Sciences ◽

10.3390/ijms21249666 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9666

Author(s):

Hyeona Hwang ◽

Hwa-Yong Lee ◽

Hojin Ryu ◽

Hyunwoo Cho

Keyword(s):

Panax Ginseng ◽

Glycogen Synthase ◽

Functional Characterization ◽

Secondary Growth ◽

Ectopic Expression ◽

Floral Organ ◽

Membrane Receptors ◽

Storage Root ◽

Functional Conservation

Brassinosteroids (BRs) play crucial roles in the physiology and development of plants. In the model plant Arabidopsis, BR signaling is initiated at the level of membrane receptors, BRASSINOSTEROIDS INSENSITIVE 1 (BRI1) and BRI1-ASSOCIATED RECEPTOR KINASE 1 (BAK1) complex, thus activating the transcription factors (TFs) BRASSINAZOLE RESISTANT 1/BRI1-EMS-SUPPRESSOR 1 (BZR1/BES1) to coordinate BR responsive genes. BRASSINOSTEROIDS INSENSITIVE 2 (BIN2), glycogen synthase kinase 3 (GSK3) like-kinase, negatively regulates BZR1/BES1 transcriptional activity through phosphorylation-dependent cytosolic retention and shuttling. However, it is still unknown whether this mechanism is conserved in Panax ginseng C. A. Mayer, a member of the Araliaceae family, which is a shade-tolerant perennial root crop. Despite its pharmacological and agricultural importance, the role of BR signaling in the development of P. ginseng and characterization of BR signaling components are still elusive. In this study, by utilizing the Arabidopsisbri1 mutant, we found that ectopic expression of the gain of function form of PgBZR1 (Pgbzr1-1D) restores BR deficiency. In detail, ectopic expression of Pgbzr1-1D rescues dwarfism, defects of floral organ development, and hypocotyl elongation of bri1-5, implying the functional conservation of PgBZR1 in P. ginseng. Interestingly, brassinolide (BL) and BRs biosynthesis inhibitor treatment in two-year-old P. ginseng storage root interferes with and promotes, respectively, secondary growth in terms of xylem formation. Altogether, our results provide new insight into the functional conservation and potential diversification of BR signaling and response in P. ginseng.

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