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Bhat M, Nambiar A, Edakkandiyil L, Abraham IM, Sen R, Negi M, Manjithaya R. A genetically-encoded fluorescence-based reporter to spatiotemporally investigate mannose-6-phosphate pathway. Mol Biol Cell 2024; 35:mr6. [PMID: 38888935 PMCID: PMC11321044 DOI: 10.1091/mbc.e23-09-0344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 06/04/2024] [Accepted: 06/12/2024] [Indexed: 06/20/2024] Open
Abstract
Maintenance of a pool of active lysosomes with acidic pH and degradative hydrolases is crucial for cell health. Abnormalities in lysosomal function are closely linked to diseases, such as lysosomal storage disorders, neurodegeneration, intracellular infections, and cancer among others. Emerging body of research suggests the malfunction of lysosomal hydrolase trafficking pathway to be a common denominator of several disease pathologies. However, available conventional tools to assess lysosomal hydrolase trafficking are insufficient and fail to provide a comprehensive picture about the trafficking flux and location of lysosomal hydrolases. To address some of the shortcomings, we designed a genetically-encoded fluorescent reporter containing a lysosomal hydrolase tandemly tagged with pH sensitive and insensitive fluorescent proteins, which can spatiotemporally trace the trafficking of lysosomal hydrolases. As a proof of principle, we demonstrate that the reporter can detect perturbations in hydrolase trafficking, that are induced by pharmacological manipulations and pathophysiological conditions like intracellular protein aggregates. This reporter can effectively serve as a probe for mapping the mechanistic intricacies of hydrolase trafficking pathway in health and disease and is a utilitarian tool to identify genetic and pharmacological modulators of this pathway, with potential therapeutic implications.
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Affiliation(s)
- Mallika Bhat
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
| | - Akshaya Nambiar
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
| | | | - Irine Maria Abraham
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
| | - Ritoprova Sen
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
| | - Mamta Negi
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
| | - Ravi Manjithaya
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
- Professor and chair, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, India
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Wang Y, Zhao J, Gu Y, Wang H, Jiang M, Zhao S, Qing H, Ni J. Cathepsin H: molecular characteristics and clues to function and mechanism. Biochem Pharmacol 2023; 212:115585. [PMID: 37148981 DOI: 10.1016/j.bcp.2023.115585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/08/2023]
Abstract
Cathepsin H (CatH) is a lysosomal cysteine protease with a unique aminopeptidase activity that is extensively expressed in the lung, pancreas, thymus, kidney, liver, skin, and brain. Owing to its specific enzymatic activity, CatH has critical effects on the regulation of biological behaviours of cancer cells and pathological processes in brain diseases. Moreover, a neutral pH level is optimal for CatH activity, so it is expected to be active in the extra-lysosomal and extracellular space. In the present review, we describe the expression, maturation, and enzymatic properties of CatH, and summarize the available experimental evidence that mechanistically links CatH to various physiological and pathological processes. Finally, we discuss the challenges and potentials of CatH inhibitors in CatH-induced disease therapy.
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Affiliation(s)
- Yanfeng Wang
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Juan Zhao
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China; Aerospace Medical Center, Aerospace Center Hospital, Beijing, 100081, China
| | - Yebo Gu
- Department of Stomatology, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, 200072, China
| | - Haiping Wang
- School of Pharmaceutical Science, Nanjing Tech University, Nanjing, China
| | - Muzhou Jiang
- Department of Periodontics, Liaoning Provincial Key Laboratory of Oral Diseases, School and Hospital of Stomatology, China Medical University, Shenyang, 110002, China
| | - Shuxuan Zhao
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Hong Qing
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
| | - Junjun Ni
- Key Laboratory of Molecular Medicine and Biotherapy, Department of Biology, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
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Wang S, Hannafon BN, Lind SE, Ding WQ. Zinc Protoporphyrin Suppresses β-Catenin Protein Expression in Human Cancer Cells: The Potential Involvement of Lysosome-Mediated Degradation. PLoS One 2015; 10:e0127413. [PMID: 26000787 PMCID: PMC4441374 DOI: 10.1371/journal.pone.0127413] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/15/2015] [Indexed: 02/05/2023] Open
Abstract
Zinc protoporphyrin (ZnPP) has been found to have anticancer activity both in vitro and in vivo. We have recently demonstrated that ZnPP diminishes β-catenin protein expression in cancer cells. The present study examined the cellular mechanisms that mediate ZnPP’s suppression of β-catenin expression. We demonstrate that ZnPP induces a rapid degradation of the β-catenin protein in cancer cells, which is accompanied by a significant inhibition of proteasome activity, suggesting that proteasome degradation does not directly account for the suppression. The possibility that ZnPP induces β-catenin exportation was rejected by the observation that there was no detectable β-catenin protein in the conditioned medium after ZnPP treatment of cancer cells. Further experimentation demonstrated that ZnPP induces lysosome membrane permeabilization, which was reversed by pretreatment with a protein transportation inhibitor cocktail containing Brefeldin A (BFA) and Monensin. More significantly, pretreatment of cancer cells with BFA and Monensin attenuated the ZnPP-induced suppression of β-catenin expression in a concentration- and time-dependent manner, indicating that the lysosome protein degradation pathway is likely involved in the ZnPP-induced suppression of β-catenin expression. Whether there is cross-talk between the ubiquitin-proteasome system and the lysosome pathway that may account for ZnPP-induced β-catenin protein degradation is currently unknown. These findings provide a novel mechanism of ZnPP’s anticancer action and reveal a potential new strategy for targeting the β-catenin Wnt signaling pathway for cancer therapy.
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Affiliation(s)
- Shuai Wang
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Bethany N. Hannafon
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Stuart E. Lind
- Departments of Pathology and Medicine, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Wei-Qun Ding
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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Akasaki K, Shiotsu K, Michihara A, Ide N, Wada I. Constitutive expression of a COOH-terminal leucine mutant of lysosome-associated membrane protein-1 causes its exclusive localization in low density intracellular vesicles. J Biochem 2014; 156:39-49. [PMID: 24695761 DOI: 10.1093/jb/mvu020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Lysosome-associated membrane protein-1 (LAMP-1) is a type I transmembrane protein with a short cytoplasmic tail that possesses a lysosome-targeting signal of GYQTI(382)-COOH. Wild-type (WT)-LAMP-1 was exclusively localized in high density lysosomes, and efficiency of LAMP-1's transport to lysosomes depends on its COOH-terminal amino acid residue. Among many different COOH-terminal amino acid substitution mutants of LAMP-1, a leucine-substituted mutant (I382L) displays the most efficient targeting to late endosomes and lysosomes [Akasaki et al. (2010) J. Biochem. 148: , 669-679]. In this study, we generated two human hepatoma cell lines (HepG2 cell lines) that stably express WT-LAMP-1 and I382L, and compared their intracellular distributions. The subcellular fractionation study using Percoll density gradient centrifugation revealed that WT-LAMP-1 had preferential localization in the high density secondary lysosomes where endogenous human LAMP-1 was enriched. In contrast, a major portion of I382L was located in a low density fraction. The low density fraction also contained approximately 80% of endogenous human LAMP-1 and significant amounts of endogenous β-glucuronidase and LAMP-2, which probably represents occurrence of low density lysosomes in the I382L-expressing cells. Double immunofluorescence microscopic analyses distinguished I382L-containing intracellular vesicles from endogenous LAMP-1-containing lysosomes and early endosomes. Altogether, constitutive expression of I382L causes its aberrant intracellular localization and generation of low density lysosomes, indicating that the COOH-terminal isoleucine is critical for normal localization of LAMP-1 in the dense lysosomes.
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Affiliation(s)
- Kenji Akasaki
- Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292; and Department of Cell Science, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Keiko Shiotsu
- Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292; and Department of Cell Science, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Akihiro Michihara
- Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292; and Department of Cell Science, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Norie Ide
- Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292; and Department of Cell Science, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Ikuo Wada
- Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292; and Department of Cell Science, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
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Bräuer AU, Nitsch R, Savaskan NE. Identification of macrophage/microglia activation factor (MAF) associated with late endosomes/lysosomes in microglial cells. FEBS Lett 2004; 563:41-8. [PMID: 15063720 DOI: 10.1016/s0014-5793(04)00244-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2004] [Revised: 02/20/2004] [Accepted: 02/25/2004] [Indexed: 11/22/2022]
Abstract
Damage to the central nervous system triggers rapid activation and specific migration of glial cells towards the lesion site. There, glial cells contribute heavily to secondary neuronal changes that take place after lesion. In an attempt to identify the molecular cues of glial activation following brain trauma we performed differential display reverse transcription-polymerase chain reaction screenings from lesioned and control hippocampus. Here we report on the identification of the macrophage/microglia activation factor (MAF), a new membrane protein with seven putative transmembrane domains. Expression analysis revealed that MAF is predominantly expressed in microglial cells in the brain, and is upregulated following brain lesion. Overexpression of MAF in non-glial cells shows an intracellular codistribution with the lysosomal marker endosome/lysosome-associated membrane protein-1 (lamp-1). Furthermore, MAF-transfected cells show that MAF is primarily associated with late endosomes/lysosomes, and that this association can be disrupted by activation of protein kinase C-dependent pathways. In conclusion, these results imply that MAF is involved in the dynamics of lysosomal membranes associated with microglial activation following brain lesion.
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Affiliation(s)
- Anja U Bräuer
- Institute of Cell Biology and Neurobiology, Center for Anatomy, Charité University Medical School Berlin, Philippstr. 12, D-10115 Berlin, Germany
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Hendricks LC, McCaffery M, Palade GE, Farquhar MG. Disruption of endoplasmic reticulum to Golgi transport leads to the accumulation of large aggregates containing beta-COP in pancreatic acinar cells. Mol Biol Cell 1993; 4:413-24. [PMID: 8507897 PMCID: PMC300942 DOI: 10.1091/mbc.4.4.413] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
When transport between the rough endoplasmic reticulum (ER) and Golgi complex is blocked by Brefeldin A (BFA) treatment or ATP depletion, the Golgi apparatus and associated transport vesicles undergo a dramatic reorganization. Because recent studies suggest that coat proteins such as beta-COP play an important role in the maintenance of the Golgi complex, we have used immunocytochemistry to determine the distribution of beta-COP in pancreatic acinar cells (PAC) in which ER to Golgi transport was blocked by BFA treatment or ATP depletion. In controls, beta-COP was associated with Golgi cisternae and transport vesicles as expected. Upon BFA treatment, PAC Golgi cisternae are dismantled and replaced by clusters of remnant vesicles surrounded by typical ER transitional elements that are generally assumed to represent the exit site of vesicular carriers for ER to Golgi transport. In BFA-treated PAC, beta-COP was concentrated in large (0.5-1.0 micron) aggregates closely associated with remnant Golgi membranes. In addition to typical ER transitional elements, we detected a new type of transitional element that consists of specialized regions of rough ER (RER) with ribosome-free ends that touched or extended into the beta-COP containing aggregates. In ATP-depleted PAC, beta-COP was not detected on Golgi membranes but was concentrated in similar large aggregates found on the cis side of the Golgi stacks. The data indicate that upon arrest of ER to Golgi transport by either BFA treatment or energy depletion, beta-COP dissociates from PAC Golgi membranes and accumulates as large aggregates closely associated with specialized ER elements. The latter may correspond to either the site of entry or exit for vesicles recycling between the Golgi and the RER.
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Affiliation(s)
- L C Hendricks
- Division of Cellular and Molecular Medicine, University of California, San Diego, La Jolla 92093
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Hendricks LC, McClanahan SL, Palade GE, Farquhar MG. Brefeldin A affects early events but does not affect late events along the exocytic pathway in pancreatic acinar cells. Proc Natl Acad Sci U S A 1992; 89:7242-6. [PMID: 1496018 PMCID: PMC49682 DOI: 10.1073/pnas.89.15.7242] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Brefeldin A (BFA) blocks protein export from the endoplasmic reticulum (ER) to Golgi complex and causes dismantling of the Golgi complex with relocation of resident Golgi proteins to the ER in some cultured cells. It is not known whether later steps in the secretory process are affected. We previously have shown that in BFA-treated rat pancreatic lobules, there is no detectable relocation of Golgi proteins to the ER and, although Golgi cisternae are rapidly dismantled, clusters of small smooth vesicles consisting of both bona fide Golgi remnants and associated vesicular carriers persist even with prolonged BFA exposure. We now report the effects of BFA on transport of proteins through the secretory pathway in exocrine pancreatic cells; we pulse-labeled pancreatic lobules with [35S]methionine and then chased for various times before adding BFA. When BFA was added at pulse, treated lobules released less than 10% of radioactive protein in comparison with controls, regardless of whether or not the lobule cultures were stimulated with carbamoylcholine. However, when lobules were pulsed and then chased for 30, 45, or 60 min before BFA addition, the amount of labeled protein released was comparable in both BFA-treated and untreated cultures. Furthermore, the kinetics and amounts of basal and carbamoylcholine-stimulated release of unlabeled alpha-amylase from storage in zymogen granules were similar in both control and BFA-treated lobules. Therefore, in the rat pancreas, BFA blocks ER to Golgi transport but does not affect later stages along the secretory pathway, including intra-Golgi transport, exit from the Golgi complex, formation and concentration of secretory granules, and exocytosis.
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Affiliation(s)
- L C Hendricks
- Division of Cellular and Molecular Medicine, University of California, San Diego, La Jolla 92093
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Damke H, Klumperman J, von Figura K, Braulke T. Effects of brefeldin A on the endocytic route. Redistribution of mannose 6-phosphate/insulin-like growth factor II receptors to the cell surface. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)54303-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Oda K, Nishimura Y, Ikehara Y, Kato K. Bafilomycin A1 inhibits the targeting of lysosomal acid hydrolases in cultured hepatocytes. Biochem Biophys Res Commun 1991; 178:369-77. [PMID: 2069575 DOI: 10.1016/0006-291x(91)91823-u] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Effects of bafilomycin A1, an inhibitor of vacuolar H(+)-ATPase, on the synthesis and processing of cathepsin D and cathepsin H were investigated in primary cultured rat hepatocytes. Pulse-chase experiments showed that after being synthesized as procathepsin D and procathepsin H the precursors were converted into mature forms in the control cells as the chase time elapsed. However, in the presence of 5 x 10(-7) M of bafilomycin A1, both precursors were largely secreted into the medium and no mature forms were found within the cells. Thus bafilomycin A1 mimics lysosomotropic amines with regard to perturbation of the targeting of lysosomal acid hydrolases. In contrast, bafilomycin A1 was found not to inhibit processings of proalbumin and procomplement component 3, which are thought to occur at the acidic trans-Golgi, implying that the proteolytic event of the proproteins is not sensitive to an increase of intra-Golgi pH. The results suggest that bafilomycin A1 is useful as a pH-perturbant to study the role of acidity in living cells.
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Affiliation(s)
- K Oda
- Department of Biochemistry, Fukuoka University School of Medicine, Japan
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Johnson MJ, Miura Y, Rubin D, Magner JA. Processing to endoglycosidase H-resistant thyrotropin subunits occurs in the presence of brefeldin-A: evidence favoring the recycling of Golgi membranes to the rough endoplasmic reticulum in mouse thyrotrophs. Thyroid 1991; 1:185-94. [PMID: 1822366 DOI: 10.1089/thy.1991.1.185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In order to assess the localization and physiologic redistribution of Golgi enzymes within mouse thyrotrophs, we studied the carbohydrate processing of TSH subunits in the presence of brefeldin A (BFA). Although this drug clearly causes endoglycosidase (endo) H-sensitive species to accumulate in most cell types, our purpose was to determine whether or not endoglycosidase H-resistant forms of free alpha-subunits and TSH subunits eventually accumulated in small but significant amounts within mouse thyrotrophic tumor cells or pituitary thyrotrophs incubated with BFA. This drug is known to block intracellular transport from the rough endoplasmic reticulum (RER) to the proximal Golgi. Stimulated thyrotrophs have been reported to have some Golgi enzymes active in their dilated RER. Accumulation of endo H-resistant forms in the presence of BFA might be explained by (1) drug-induced enhancement of Golgi to RER membrane recycling with further aberrant distribution of Golgi enzymes or (2) an uncharacteristic trapping of glycoproteins within Golgi elements that might be an unusual action of BFA peculiar to thyrotrophs. Free alpha-subunits and TSH were labeled in mouse thyrotrophic tumor tissue or pituitaries incubated in pulse-chase fashion with [35S]methionine in the absence or presence of BFA, carboxyl cyanide m-chlorophylhydrazone (CCCP), or swainsonine. The results in tumor and pituitary tissue were similar. In incubations without drugs, most TSH subunits (greater than 90%) became endo H-resistant after 5-h chase, and the majority (greater than 85%) were secreted. Doses of CCCP and BFA were selected that generally blocked the secretion of TSH subunits by greater than 85% (in some cases greater than 99%), presumably because of accumulation of secretory proteins in the RER. Yet, in the presence of CCCP, 35% and 42% of intracellular free alpha-subunits and TSH subunits, respectively, became endo H-resistant at 5 h chase. Compared to control incubations, intracellular subunits tended to remain endo H-sensitive in the presence of BFA, yet, compared to CCCP incubations, BFA slightly enhanced the attainment of endo H-resistance by free alpha-subunits and TSH subunits to 55% and 52%, respectively. Pretreatment of tumor tissue with BFA allowed more endo H-resistant species to appear, even during coincubation with CCCP. These data suggest that Golgi enzymes cycle back to the dilated RER of active thyrotrophs and that this phenomenon is enhanced by BFA.
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Affiliation(s)
- M J Johnson
- Division of Endocrinology, Michael Reese Hospital, University of Illinois, Chicago
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Kneusel RE, Matern U, Wray V, Klöppel KD. Detoxification of the macrolide toxin brefeldin A by Bacillus subtilis. FEBS Lett 1990; 275:107-10. [PMID: 2124541 DOI: 10.1016/0014-5793(90)81450-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The macrolide toxin brefeldin A is a determinant of Alternaria leaf blight disease in safflower, which causes severe economic losses worldwide. Soilborne bacteria, classified as Bacillus subtilis spp., were isolated and shown to readily metabolize brefeldin A in laboratory culture to one major product. This product was identified by high resolution 2D 1H NMR and FAB mass spectroscopies as the acid resulting from hydrolysis of the macrolide ring in brefeldin A . In contrast to brefeldin A, the acid completely lacked phytotoxic activity in the standard leaf bioassay. Detoxification of brefeldin A by the lactonase activity from Bacillus subtilis may be exploited in the future to introduce resistance to Alternaria leaf blight in safflower.
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Affiliation(s)
- R E Kneusel
- Lehrstuhl für Biochemie der Pflanzen, Universität Freiburg, FRG
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