1
|
Spears BJ, Howton TC, Gao F, Garner CM, Mukhtar MS, Gassmann W. Direct Regulation of the EFR-Dependent Immune Response by Arabidopsis TCP Transcription Factors. Mol Plant Microbe Interact 2019; 32:540-549. [PMID: 30480481 DOI: 10.1094/mpmi-07-18-0201-fi] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
One layer of the innate immune system allows plants to recognize pathogen-associated molecular patterns (PAMPS), activating a defense response known as PAMP-triggered immunity (PTI). Maintaining an active immune response, however, comes at the cost of plant growth and development; accordingly, optimization of the balance between defense and development is critical to plant fitness. The TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factor family consists of well-characterized transcriptional regulators of plant development and morphogenesis. The three closely related class I TCP transcription factors TCP8, TCP14, and TCP15 have also been implicated in the regulation of effector-triggered immunity, but there has been no previous characterization of PTI-related phenotypes. To identify TCP targets involved in PTI, we screened a PAMP-induced gene promoter library in a yeast one-hybrid assay and identified interactions of these three TCPs with the EF-Tu RECEPTOR (EFR) promoter. The direct interactions between TCP8 and EFR were confirmed to require an intact TCP binding site in planta. A tcp8 tcp14 tcp15 triple mutant was impaired in EFR-dependent PTI and exhibited reduced levels of PATHOGENESIS-RELATED PROTEIN 2 and induction of EFR expression after elicitation with elf18 but also increased production of reactive oxygen species relative to Col-0. Our data support an increasingly complex role for TCPs at the nexus of plant development and defense.
Collapse
Affiliation(s)
- Benjamin J Spears
- 1 Division of Plant Sciences, University of Missouri, Columbia, MO 65211-7310, U.S.A
- 2 C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri
| | - T C Howton
- 3 Department of Biology, University of Alabama, Birmingham, AL, 35233, U.S.A.; and
| | - Fei Gao
- 1 Division of Plant Sciences, University of Missouri, Columbia, MO 65211-7310, U.S.A
- 2 C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri
| | - Christopher M Garner
- 2 C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri
- 4 Division of Biological Sciences, University of Missouri
| | - M Shahid Mukhtar
- 3 Department of Biology, University of Alabama, Birmingham, AL, 35233, U.S.A.; and
| | - Walter Gassmann
- 1 Division of Plant Sciences, University of Missouri, Columbia, MO 65211-7310, U.S.A
- 2 C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri
| |
Collapse
|
2
|
Garner CM, Kim SH, Spears BJ, Gassmann W. Express yourself: Transcriptional regulation of plant innate immunity. Semin Cell Dev Biol 2016; 56:150-162. [PMID: 27174437 DOI: 10.1016/j.semcdb.2016.05.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Revised: 05/03/2016] [Accepted: 05/04/2016] [Indexed: 12/19/2022]
Abstract
The plant immune system is a complex network of components that function together to sense the presence and activity of potential biotic threats, and integrate these signals into an appropriate output, namely the transcription of genes that activate an immune response that is commensurate with the perceived threat. Given the variety of biotic threats a plant must face the immune response must be plastic, but because an immune response is costly to the plant in terms of energy expenditure and development it must also be under tight control. To meet these needs transcriptional control is exercised at multiple levels. In this article we will review some of the latest developments in understanding how the plant immune response is regulated at the level of transcription. New roles are being discovered for the long-studied WRKY and TGA transcription factor families, while additional critical defense functions are being attributed to TCPs and other transcription factors. Dynamically controlling access to DNA through post-translational modification of histones is emerging as an essential component of priming, maintaining, attenuating, and repressing transcription in response to biotic stress. Unsurprisingly, the plant's transcriptional response is targeted by pathogen effectors, and in turn resistance proteins stand guard over and participate in transcriptional regulation. Together, these multiple layers lead to the observed complexity of the plant transcriptional immune response, with different transcription factors or chromatin components playing a prominent role depending on the plant-pathogen interaction being studied.
Collapse
Affiliation(s)
- Christopher M Garner
- Division of Biological Sciences, University of Missouri, Columbia, MO, USA; C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA
| | - Sang Hee Kim
- Division of Plant Sciences, University of Missouri, Columbia, MO, USA; C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA
| | - Benjamin J Spears
- Division of Plant Sciences, University of Missouri, Columbia, MO, USA; C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA
| | - Walter Gassmann
- Division of Plant Sciences, University of Missouri, Columbia, MO, USA; C.S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, MO, USA.
| |
Collapse
|
3
|
Bhattacharjee S, Garner CM, Gassmann W. New clues in the nucleus: transcriptional reprogramming in effector-triggered immunity. Front Plant Sci 2013; 4:364. [PMID: 24062762 PMCID: PMC3772313 DOI: 10.3389/fpls.2013.00364] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/27/2013] [Indexed: 05/05/2023]
Abstract
The robustness of plant effector-triggered immunity is correlated with massive alterations of the host transcriptome. Yet the molecular mechanisms that cause and underlie this reprogramming remain obscure. Here we will review recent advances in deciphering nuclear functions of plant immune receptors and of associated proteins. Important open questions remain, such as the identities of the primary transcription factors involved in control of effector-triggered immune responses, and indeed whether this can be generalized or whether particular effector-resistance protein interactions impinge on distinct sectors in the transcriptional response web. Multiple lines of evidence have implicated WRKY transcription factors at the core of responses to microbe-associated molecular patterns and in intersections with effector-triggered immunity. Recent findings from yeast two-hybrid studies suggest that members of the TCP transcription factor family are targets of several effectors from diverse pathogens. Additional transcription factor families that are directly or indirectly involved in effector-triggered immunity are likely to be identified.
Collapse
Affiliation(s)
- Saikat Bhattacharjee
- Division of Plant Sciences, University of MissouriColumbia, MO, USA
- Christopher S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of MissouriColumbia, MO, USA
- *Correspondence: Saikat Bhattacharjee, Division of Plant Sciences, University of Missouri, 314, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA e-mail:
| | - Christopher M. Garner
- Christopher S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of MissouriColumbia, MO, USA
- Division of Biological Sciences, University of MissouriColumbia, MO, USA
| | - Walter Gassmann
- Division of Plant Sciences, University of MissouriColumbia, MO, USA
- Christopher S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of MissouriColumbia, MO, USA
| |
Collapse
|
4
|
Abstract
Much improvement in the treatment of ovarian cancer has been achieved since the introduction of platinum compounds in the 1980s, with the result that single-agent platinum-based therapy following primary surgery is now the standard treatment for advanced ovarian cancer. The main therapeutic effect of chemotherapy is based on the sensitivity of the patient's tumour to the drug. However, testing a new chemical compound on humans requires much care, time and resources, whereas prior testing of drugs on cancer cell lines may indicate those drugs particularly suited to treatment of a specific disease. This study investigates the actions of two established platinum-based chemotherapeutic agents (cisplatin and carboplatin) on a panel of 10 human ovarian cancer cell lines. Each cell line was plated onto 96-well tissue culture plates, incubated for 72 hours with the drug, formalin-fixed and then assessed using the methylene blue colorimetric microassay to detect viable cells. The IC50 values for each cell line were calculated in order to assess the toxicity of each drug, and a wide range of responses were observed across the 10 cell lines investigated. This suggests that the panel reflected the heterogeneous nature of ovarian cancer, a malignancy in which a huge range of drug sensitivities can be seen even among tumours of the same histological type. The results indicate that the panel could be of use either as a primary screen to test new drugs against ovarian cancer or to investigate the drug resistance that is so common in this disease.
Collapse
Affiliation(s)
- C M Garner
- Oncology Research Laboratory, Derby Cancer Centre, Derby City General Hospital.
| | | | | |
Collapse
|
5
|
Hubbold LM, Garner CM, Chakraborti PR. Measuring the effect of different agents on the viscosity of biological fluids: a novel method. Br J Biomed Sci 2001; 58:33-6. [PMID: 11284222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Affiliation(s)
- L M Hubbold
- Oncology Research Laboratory, Derby Cancer Centre, Derby City General Hospital, Uttoxeter Road, Derby DE22 3NE, UK
| | | | | |
Collapse
|
6
|
Garner CM, Hubbold LM, Chakraborti PR. Mycoplasma detection in cell cultures: a comparison of four methods. Br J Biomed Sci 2001; 57:295-301. [PMID: 11204859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Mycoplasma is a common contaminant of tissue culture samples. Infection is persistent, difficult to detect and diagnose, and very difficult to cure. The concentration of mycoplasma in infected cultures can be as high as 10(7) colony-forming units per mL, and their presence can change many of the cell reactions, including altering cell growth rate, inducing morphological changes or cell transformation, and mimicking virus infection. Therefore, it should be assumed that a mycoplasma-contaminated cell line may be significantly influenced in every respect, and, thus, experimental data derived from such a cell line is likely to be invalid. Contamination is not obvious, either macroscopically or microscopically; thus, routine mycoplasma testing is essential for any cell culture laboratory. Many of the testing procedures developed so far are time-consuming, expensive, inconclusive and unsuitable for screening large numbers of test specimens. This study compares DNA staining, enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR) and PCR ELISA, to determine which is the best procedure for routine assessment of cell cultures. All four methods gave reproducible results with both infected and non-infected cell lines. Both ELISA methods were easy to perform, reproducible and easily interpreted.
Collapse
Affiliation(s)
- C M Garner
- Oncology Research Laboratory, Derby Cancer Centre, Derby City General Hospital, Uttoxeter Road, Derby DE22 3NE, UK
| | | | | |
Collapse
|
7
|
Garner CM. Cancer-related spinal cord compression. Am J Nurs 1999; 99:34-5. [PMID: 10410129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
|
8
|
|
9
|
Abstract
The Attitudes Toward Obesity Scale was administered to 23 male and 45 female caregivers and 55 patients. There were no sex differences in reported negative feelings of caregivers, but the obese patients reported significantly more negative attitudes of caregivers than did the nonobese patients.
Collapse
Affiliation(s)
- C M Garner
- Jacksonville University, FL 32211-3394, USA
| | | |
Collapse
|
10
|
Abstract
Positron emission tomography (PET), the newest of the nuclear medicine imaging instruments, is now being used for diagnosis in 20 clinical sites in the United States. Recent approval of third-party reimbursement for PET scans for selected illnesses has set the precedence for wider clinical applications of this advanced diagnostic tool. Most practical of the newest applications of PET in the US is in early detection of recurrent brain tumors. Early detection not only saves lives, but also may save thousands of dollars in unnecessary tests, treatments, and surgeries. PET has two basic advantages over computerized tomography (CT) scans and magnetic resonance imaging (MRI). First, PET creates vastly superior images of metabolic activity, making possible more accurate and detailed diagnoses. Secondly, PET causes very low radiation absorption due to the volatile nature of the radioisotopes used. The rapidly increasing use of PET in clinical situations requires the nurse to become aware of its basic principles and applications, as well as the nursing care involved when a client is scheduled for a PET scan. This study serves to explain basic physical principles employed by PET. The historical development of PET and the comparison of PET with x-ray, CT, and MRI are reviewed. The article concludes with a discussion of future oncologic applications and the latest research developments in clinical use of PET scans.
Collapse
Affiliation(s)
- C M Garner
- Department of Nursing, Jacksonville University, FL 32211, USA
| |
Collapse
|
11
|
Garner CM, Richards GM, Adu D, Pall AA, Taylor CM, Richards NT, Michael J. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression and function on cultured human glomerular epithelial cells. Clin Exp Immunol 1994; 95:322-6. [PMID: 7508348 PMCID: PMC1534934 DOI: 10.1111/j.1365-2249.1994.tb06531.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Glomerular epithelial cells are involved in extracapillary inflammation (crescents) but the mechanisms of this extracapillary accumulation of macrophages, epithelial cells and occasional lymphocytes are unknown. Human glomerular parietal epithelial cells express ICAM-1 and VCAM-1 on immunohistological stains of renal biopsies. We studied the expression of these cell adhesion molecules on cultured human glomerular epithelial cells (HGEC), their regulation by pro-inflammatory cytokines, and their role in mediating the adhesion of concanavalin A (Con A)-activated peripheral blood mononuclear cells. Human glomerular epithelial cells in culture constitutively express ICAM-1 and VCAM-1. The expression of ICAM-1 was not significantly altered by tumour necrosis factor-alpha (TNF-alpha) (P = 0.32), IL-1 beta (P = 0.24), interferon-gamma (IFN-gamma) (P = 0.66) or IL-4 (P = 0.85). VCAM-1 expression was increased by all four cytokines, but only significantly so by IL-4 (P = 0.0001). Con A-stimulated, monocyte-depleted peripheral blood lymphocytes bound to human glomerular epithelial cells, median 28.9% (range 14.5-37.9%). This adherence was significantly inhibited by anti-ICAM-1 (P = 0.03) and anti-LFA-1 (P = 0.02), but not by anti-VCAM-1 (P = 0.13) or by antibody to von Willebrand factor (P = NS). The interaction between ICAM-1 on HGEC and LFA-1 on mononuclear cells may be important in the pathogenesis of extracapillary inflammation in glomerulonephritis.
Collapse
Affiliation(s)
- C M Garner
- Renal Research Laboratory, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK
| | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
The uptake and release of radiochromium from adult human vascular endothelial cells in culture was employed to determine the relative toxicity of different bile salts. Endothelial cells after pre-incubation with 51Cr for 18 h were incubated with bile salts for 24 h and percentage chromium release was taken as a measure of toxicity to cells. Lithocholic acid (LC) (potassium salt) was cytotoxic at concentrations greater than 50 microM. However, LC glucuronide, sulfate and the beta-epimer were progressively less toxic with toxicity seen at concentrations of 60, 110 and 180 microM, respectively. The greatest cytotoxic effect was observed with glycolithocholic acid (GLC) (potassium salt) which was toxic at every concentration tested (20-200 microM). Sulfation abolished the toxic effect of GLC. At the concentrations employed for the assay (between 20 and 240 microM) GLC sulfate (disodium salt), taurolithocholic acid sulfate (disodium salt), cholic acid (sodium salt), glycocholic acid (sodium salt), deoxycholic acid (sodium salt) and ursodeoxycholic acid (sodium salt) were not cytotoxic. The 51Cr release cytotoxicity assay was validated with lactate dehydrogenase leakage from endothelial cells with a good correlation (r = 0.87). These data confirm in a human cellular system that LC and its conjugates were the most toxic of the bile salts tested and explains its pathophysiological importance in hepatobiliary disease. It also suggests that biotransformation by either sulfation or beta-epimerisation of bile salts especially of LC, as occurs in patients with intrahepatic or extrahepatic biliary obstruction or severe cholestasis, is hepatoprotective.
Collapse
Affiliation(s)
- C M Garner
- Liver Research Laboratories, Queen Elizabeth Hospital, Edgbaston, Birmingham, U.K
| | | | | | | |
Collapse
|
13
|
Blann AD, Garner CM. Indium 111 (111In) as a label for endothelial cells and fibroblasts used as target cells in cytotoxicity tests. Med Lab Sci 1985; 42:92-4. [PMID: 3982251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
14
|
Taylor AM, Flude E, Garner CM, Campbell JB, Edwards MJ. Effects of the DNA strand-cleaving antitumor agent, streptonigrin, on ataxia telangiectasia cells. Cancer Res 1983; 43:2700-3. [PMID: 6850587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cells from patients with ataxia telangiectasia (A-T) were shown to be more sensitive to streptonigrin than were cells from normal individuals. A linear dose-dependent cell survival was observed for both normal and A-T cells exposed to streptonigrin (up to 1.5 ng/ml) for 3-hr, with the A-T cells being about twice as sensitive as were the normal cells (Do approximately 0.25 ng compared with Do approximately 0.5 ng). The extreme toxicity of streptonigrin is also seen in the response of DNA synthesis which is inhibited sharply in both A-T and normal cells using doses of up to 125 ng/ml, although the effect was less pronounced in A-T cells. A greater amount of time was needed for recovery of DNA synthesis in normal cells compared with that of A-T cells. Finally, chromosomes from both A-T lymphocytes and fibroblasts show about a doubling of breakage rate following exposure to streptonigrin. The increased sensitivity of A-T cells to streptonigrin appears to be fairly comparable to the sensitivity to ionizing radiation, bleomycin, or neocarzinostatin and provides further evidence that perhaps A-T cells are deficient in some form of DNA strand repair.
Collapse
|