Lysine synthesis and catabolism are coordinately regulated during tobacco seed development
The regulation of synthesis and accumulation of the essential amino acid lysine was studied in seeds of transgenic tobacco plants expressing, in a seed-specific manner, two feedback-insensitive bacterial enzymes: dihydrodipicolinate synthase (EC 4.2.1.52) and aspartate kinase (EC 2.7.2.4). High-leve...
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| Veröffentlicht in: | Proceedings of the National Academy of Sciences - PNAS 1994-03, Vol.91 (7), p.2577-2581 |
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| creator | Karchi, H Shaul, O Galili, G |
| description | The regulation of synthesis and accumulation of the essential amino acid lysine was studied in seeds of transgenic tobacco plants expressing, in a seed-specific manner, two feedback-insensitive bacterial enzymes: dihydrodipicolinate synthase (EC 4.2.1.52) and aspartate kinase (EC 2.7.2.4). High-level expression of the two bacterial enzymes resulted in only a slight increase in free lysine accumulation at intermediate stages of seed development, while free lysine declined to the low level of control plants toward maturity. To test whether enhanced catabolism may have contributed to the failure of free lysine to accumulate in seeds of transgenic plants, we analyzed the activity of lysine-ketoglutarate reductase (EC 1.5.1.7), an enzyme that catabolizes lysine into saccharopine. In both the control and the transgenic plants, the timing of appearance of lysine-ketoglutarate reductase activity correlated very closely with that of dihydrodipicolinate synthase activity, suggesting that lysine synthesis and catabolism were coordinately regulated during seed development. Notably, the activity of lysine-ketoglutarate reductase was significantly higher in seeds of the transgenic plants than in the controls. Coexpression of both bacterial enzymes in the same plant resulted in a significant increase in the proportions of lysine and threonine in seed albumins. Apparently, the normal low steady-state levels of free lysine and threonine in tobacco seeds may be rate limiting for the synthesis of seed proteins, which are relatively rich in these amino acids. |
| doi_str_mv | 10.1073/pnas.91.7.2577 |
| format | Article |
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High-level expression of the two bacterial enzymes resulted in only a slight increase in free lysine accumulation at intermediate stages of seed development, while free lysine declined to the low level of control plants toward maturity. To test whether enhanced catabolism may have contributed to the failure of free lysine to accumulate in seeds of transgenic plants, we analyzed the activity of lysine-ketoglutarate reductase (EC 1.5.1.7), an enzyme that catabolizes lysine into saccharopine. In both the control and the transgenic plants, the timing of appearance of lysine-ketoglutarate reductase activity correlated very closely with that of dihydrodipicolinate synthase activity, suggesting that lysine synthesis and catabolism were coordinately regulated during seed development. Notably, the activity of lysine-ketoglutarate reductase was significantly higher in seeds of the transgenic plants than in the controls. Coexpression of both bacterial enzymes in the same plant resulted in a significant increase in the proportions of lysine and threonine in seed albumins. Apparently, the normal low steady-state levels of free lysine and threonine in tobacco seeds may be rate limiting for the synthesis of seed proteins, which are relatively rich in these amino acids.</description><identifier>ISSN: 0027-8424</identifier><identifier>EISSN: 1091-6490</identifier><identifier>DOI: 10.1073/pnas.91.7.2577</identifier><identifier>PMID: 8146157</identifier><identifier>CODEN: PNASA6</identifier><language>eng</language><publisher>Washington, DC: National Academy of Sciences of the United States of America</publisher><subject>ACIDE AMINE ; ACTIVIDAD ENZIMATICA ; ACTIVITE ENZYMATIQUE ; Albumins ; Amino acids ; AMINOACIDOS ; Aspartate Kinase - genetics ; Aspartate Kinase - metabolism ; Biological and medical sciences ; Catabolism ; Enzymes ; Flowering ; Fundamental and applied biological sciences. Psychology ; GENE ; Gene Expression Regulation ; GENES ; Genotypes ; GRAINE ; Hydro-Lyases - genetics ; Hydro-Lyases - metabolism ; LIASAS ; LISINA ; LYASE ; LYSINE ; Lysine - biosynthesis ; Metabolism ; METABOLISME ; METABOLISMO ; Nicotiana - growth & development ; Nicotiana - metabolism ; NICOTIANA TABACUM ; Nitrogen metabolism ; OXIDORREDUCTASAS ; OXYDOREDUCTASE ; Plant physiology and development ; Plant Proteins - biosynthesis ; Plants ; Plants, Genetically Modified ; Plants, Toxic ; Recombinant Fusion Proteins - metabolism ; Saccharopine Dehydrogenases - metabolism ; Seed development ; Seeds ; Seeds - growth & development ; Seeds - metabolism ; SEMILLA ; Threonine - biosynthesis ; Tobacco ; TRANSFERASAS ; TRANSFERASE ; TRANSFERENCIA DE GENES ; TRANSFERT DE GENE ; Transgenic plants</subject><ispartof>Proceedings of the National Academy of Sciences - PNAS, 1994-03, Vol.91 (7), p.2577-2581</ispartof><rights>Copyright 1994 The National Academy of Sciences of the United States of America</rights><rights>1994 INIST-CNRS</rights><rights>Copyright National Academy of Sciences Mar 29, 1994</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c568t-5b22e35154738e90766967cbb80232b5c6024ba994167ecba2d60b5a9aed86673</citedby></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Uhttp://www.pnas.org/content/91/7.cover.gif</thumbnail><linktopdf>$$Uhttps://www.jstor.org/stable/pdf/2364277$$EPDF$$P50$$Gjstor$$H</linktopdf><linktohtml>$$Uhttps://www.jstor.org/stable/2364277$$EHTML$$P50$$Gjstor$$H</linktohtml><link.rule.ids>230,309,310,314,723,776,780,785,786,799,881,23909,23910,25118,27901,27902,53766,53768,57992,58225</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=4172057$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/8146157$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Karchi, H</creatorcontrib><creatorcontrib>Shaul, O</creatorcontrib><creatorcontrib>Galili, G</creatorcontrib><title>Lysine synthesis and catabolism are coordinately regulated during tobacco seed development</title><title>Proceedings of the National Academy of Sciences - PNAS</title><addtitle>Proc Natl Acad Sci U S A</addtitle><description>The regulation of synthesis and accumulation of the essential amino acid lysine was studied in seeds of transgenic tobacco plants expressing, in a seed-specific manner, two feedback-insensitive bacterial enzymes: dihydrodipicolinate synthase (EC 4.2.1.52) and aspartate kinase (EC 2.7.2.4). High-level expression of the two bacterial enzymes resulted in only a slight increase in free lysine accumulation at intermediate stages of seed development, while free lysine declined to the low level of control plants toward maturity. To test whether enhanced catabolism may have contributed to the failure of free lysine to accumulate in seeds of transgenic plants, we analyzed the activity of lysine-ketoglutarate reductase (EC 1.5.1.7), an enzyme that catabolizes lysine into saccharopine. In both the control and the transgenic plants, the timing of appearance of lysine-ketoglutarate reductase activity correlated very closely with that of dihydrodipicolinate synthase activity, suggesting that lysine synthesis and catabolism were coordinately regulated during seed development. Notably, the activity of lysine-ketoglutarate reductase was significantly higher in seeds of the transgenic plants than in the controls. Coexpression of both bacterial enzymes in the same plant resulted in a significant increase in the proportions of lysine and threonine in seed albumins. Apparently, the normal low steady-state levels of free lysine and threonine in tobacco seeds may be rate limiting for the synthesis of seed proteins, which are relatively rich in these amino acids.</description><subject>ACIDE AMINE</subject><subject>ACTIVIDAD ENZIMATICA</subject><subject>ACTIVITE ENZYMATIQUE</subject><subject>Albumins</subject><subject>Amino acids</subject><subject>AMINOACIDOS</subject><subject>Aspartate Kinase - genetics</subject><subject>Aspartate Kinase - metabolism</subject><subject>Biological and medical sciences</subject><subject>Catabolism</subject><subject>Enzymes</subject><subject>Flowering</subject><subject>Fundamental and applied biological sciences. Psychology</subject><subject>GENE</subject><subject>Gene Expression Regulation</subject><subject>GENES</subject><subject>Genotypes</subject><subject>GRAINE</subject><subject>Hydro-Lyases - genetics</subject><subject>Hydro-Lyases - metabolism</subject><subject>LIASAS</subject><subject>LISINA</subject><subject>LYASE</subject><subject>LYSINE</subject><subject>Lysine - biosynthesis</subject><subject>Metabolism</subject><subject>METABOLISME</subject><subject>METABOLISMO</subject><subject>Nicotiana - growth & development</subject><subject>Nicotiana - metabolism</subject><subject>NICOTIANA TABACUM</subject><subject>Nitrogen metabolism</subject><subject>OXIDORREDUCTASAS</subject><subject>OXYDOREDUCTASE</subject><subject>Plant physiology and development</subject><subject>Plant Proteins - biosynthesis</subject><subject>Plants</subject><subject>Plants, Genetically Modified</subject><subject>Plants, Toxic</subject><subject>Recombinant Fusion Proteins - metabolism</subject><subject>Saccharopine Dehydrogenases - metabolism</subject><subject>Seed development</subject><subject>Seeds</subject><subject>Seeds - growth & development</subject><subject>Seeds - metabolism</subject><subject>SEMILLA</subject><subject>Threonine - biosynthesis</subject><subject>Tobacco</subject><subject>TRANSFERASAS</subject><subject>TRANSFERASE</subject><subject>TRANSFERENCIA DE GENES</subject><subject>TRANSFERT DE GENE</subject><subject>Transgenic plants</subject><issn>0027-8424</issn><issn>1091-6490</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>1994</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNp9kc-LEzEcxYMoa129ehCFQcRbxySTHxPYiyy7KhQ86F68hG8yme6UaVKTzGL_ezO2lnrxlJD3ee_7JQ-hlwTXBMvmw85DqhWpZU25lI_QgmBFloIp_BgtMKZy2TLKnqJnKW0wxoq3-AJdtIQJwuUC_Vjt0-BdlfY-37s0pAp8V1nIYMI4pG0F0VU2hNgNHrIb91V062ks167qpjj4dZWDAWtDldz85h7cGHZb5_Nz9KSHMbkXx_MS3d3efL_-vFx9_fTl-uNqablo85IbSl3DCWeyaZ3CUgglpDWmxbShhluBKTOgFCNCOmuAdgIbDgpc1wohm0t0dcjdTWbrOltGRxj1Lg5biHsdYND_Kn641-vwoFnDCC32t0d7DD8nl7LehCn6srGmmBSkjC9QfYBsDClF15_iCdZzD3ruQSuipZ57KIY350ud8OPHF_3dUYdkYewjeDukE8aIpJifx8zxf9XzMe__p-t-GsfsfuUCvj6Am5RDPJG0EYz-yXl1kHsIGtaxrHL3TTFOMGfNb47ou3E</recordid><startdate>19940329</startdate><enddate>19940329</enddate><creator>Karchi, H</creator><creator>Shaul, O</creator><creator>Galili, G</creator><general>National Academy of Sciences of the United States of America</general><general>National Acad Sciences</general><general>National Academy of Sciences</general><scope>FBQ</scope><scope>IQODW</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7QG</scope><scope>7QL</scope><scope>7QP</scope><scope>7QR</scope><scope>7SN</scope><scope>7SS</scope><scope>7T5</scope><scope>7TK</scope><scope>7TM</scope><scope>7TO</scope><scope>7U9</scope><scope>8FD</scope><scope>C1K</scope><scope>FR3</scope><scope>H94</scope><scope>M7N</scope><scope>P64</scope><scope>RC3</scope><scope>5PM</scope></search><sort><creationdate>19940329</creationdate><title>Lysine synthesis and catabolism are coordinately regulated during tobacco seed development</title><author>Karchi, H ; Shaul, O ; Galili, G</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c568t-5b22e35154738e90766967cbb80232b5c6024ba994167ecba2d60b5a9aed86673</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>1994</creationdate><topic>ACIDE AMINE</topic><topic>ACTIVIDAD ENZIMATICA</topic><topic>ACTIVITE ENZYMATIQUE</topic><topic>Albumins</topic><topic>Amino acids</topic><topic>AMINOACIDOS</topic><topic>Aspartate Kinase - genetics</topic><topic>Aspartate Kinase - metabolism</topic><topic>Biological and medical sciences</topic><topic>Catabolism</topic><topic>Enzymes</topic><topic>Flowering</topic><topic>Fundamental and applied biological sciences. Psychology</topic><topic>GENE</topic><topic>Gene Expression Regulation</topic><topic>GENES</topic><topic>Genotypes</topic><topic>GRAINE</topic><topic>Hydro-Lyases - genetics</topic><topic>Hydro-Lyases - metabolism</topic><topic>LIASAS</topic><topic>LISINA</topic><topic>LYASE</topic><topic>LYSINE</topic><topic>Lysine - biosynthesis</topic><topic>Metabolism</topic><topic>METABOLISME</topic><topic>METABOLISMO</topic><topic>Nicotiana - growth & development</topic><topic>Nicotiana - metabolism</topic><topic>NICOTIANA TABACUM</topic><topic>Nitrogen metabolism</topic><topic>OXIDORREDUCTASAS</topic><topic>OXYDOREDUCTASE</topic><topic>Plant physiology and development</topic><topic>Plant Proteins - biosynthesis</topic><topic>Plants</topic><topic>Plants, Genetically Modified</topic><topic>Plants, Toxic</topic><topic>Recombinant Fusion Proteins - metabolism</topic><topic>Saccharopine Dehydrogenases - metabolism</topic><topic>Seed development</topic><topic>Seeds</topic><topic>Seeds - growth & development</topic><topic>Seeds - metabolism</topic><topic>SEMILLA</topic><topic>Threonine - biosynthesis</topic><topic>Tobacco</topic><topic>TRANSFERASAS</topic><topic>TRANSFERASE</topic><topic>TRANSFERENCIA DE GENES</topic><topic>TRANSFERT DE GENE</topic><topic>Transgenic plants</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Karchi, H</creatorcontrib><creatorcontrib>Shaul, O</creatorcontrib><creatorcontrib>Galili, G</creatorcontrib><collection>AGRIS</collection><collection>Pascal-Francis</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Animal Behavior Abstracts</collection><collection>Bacteriology Abstracts (Microbiology B)</collection><collection>Calcium & Calcified Tissue Abstracts</collection><collection>Chemoreception Abstracts</collection><collection>Ecology Abstracts</collection><collection>Entomology Abstracts (Full archive)</collection><collection>Immunology Abstracts</collection><collection>Neurosciences Abstracts</collection><collection>Nucleic Acids Abstracts</collection><collection>Oncogenes and Growth Factors Abstracts</collection><collection>Virology and AIDS Abstracts</collection><collection>Technology Research Database</collection><collection>Environmental Sciences and Pollution Management</collection><collection>Engineering Research Database</collection><collection>AIDS and Cancer Research Abstracts</collection><collection>Algology Mycology and Protozoology Abstracts (Microbiology C)</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>Genetics Abstracts</collection><collection>PubMed Central (Full Participant titles)</collection><jtitle>Proceedings of the National Academy of Sciences - PNAS</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Karchi, H</au><au>Shaul, O</au><au>Galili, G</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Lysine synthesis and catabolism are coordinately regulated during tobacco seed development</atitle><jtitle>Proceedings of the National Academy of Sciences - PNAS</jtitle><addtitle>Proc Natl Acad Sci U S A</addtitle><date>1994-03-29</date><risdate>1994</risdate><volume>91</volume><issue>7</issue><spage>2577</spage><epage>2581</epage><pages>2577-2581</pages><issn>0027-8424</issn><eissn>1091-6490</eissn><coden>PNASA6</coden><abstract>The regulation of synthesis and accumulation of the essential amino acid lysine was studied in seeds of transgenic tobacco plants expressing, in a seed-specific manner, two feedback-insensitive bacterial enzymes: dihydrodipicolinate synthase (EC 4.2.1.52) and aspartate kinase (EC 2.7.2.4). High-level expression of the two bacterial enzymes resulted in only a slight increase in free lysine accumulation at intermediate stages of seed development, while free lysine declined to the low level of control plants toward maturity. To test whether enhanced catabolism may have contributed to the failure of free lysine to accumulate in seeds of transgenic plants, we analyzed the activity of lysine-ketoglutarate reductase (EC 1.5.1.7), an enzyme that catabolizes lysine into saccharopine. In both the control and the transgenic plants, the timing of appearance of lysine-ketoglutarate reductase activity correlated very closely with that of dihydrodipicolinate synthase activity, suggesting that lysine synthesis and catabolism were coordinately regulated during seed development. Notably, the activity of lysine-ketoglutarate reductase was significantly higher in seeds of the transgenic plants than in the controls. Coexpression of both bacterial enzymes in the same plant resulted in a significant increase in the proportions of lysine and threonine in seed albumins. Apparently, the normal low steady-state levels of free lysine and threonine in tobacco seeds may be rate limiting for the synthesis of seed proteins, which are relatively rich in these amino acids.</abstract><cop>Washington, DC</cop><pub>National Academy of Sciences of the United States of America</pub><pmid>8146157</pmid><doi>10.1073/pnas.91.7.2577</doi><tpages>5</tpages><oa>free_for_read</oa></addata></record> |
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| source | Jstor Complete Legacy; MEDLINE; PubMed Central; Alma/SFX Local Collection; Free Full-Text Journals in Chemistry |
| subjects | ACIDE AMINE ACTIVIDAD ENZIMATICA ACTIVITE ENZYMATIQUE Albumins Amino acids AMINOACIDOS Aspartate Kinase - genetics Aspartate Kinase - metabolism Biological and medical sciences Catabolism Enzymes Flowering Fundamental and applied biological sciences. Psychology GENE Gene Expression Regulation GENES Genotypes GRAINE Hydro-Lyases - genetics Hydro-Lyases - metabolism LIASAS LISINA LYASE LYSINE Lysine - biosynthesis Metabolism METABOLISME METABOLISMO Nicotiana - growth & development Nicotiana - metabolism NICOTIANA TABACUM Nitrogen metabolism OXIDORREDUCTASAS OXYDOREDUCTASE Plant physiology and development Plant Proteins - biosynthesis Plants Plants, Genetically Modified Plants, Toxic Recombinant Fusion Proteins - metabolism Saccharopine Dehydrogenases - metabolism Seed development Seeds Seeds - growth & development Seeds - metabolism SEMILLA Threonine - biosynthesis Tobacco TRANSFERASAS TRANSFERASE TRANSFERENCIA DE GENES TRANSFERT DE GENE Transgenic plants |
| title | Lysine synthesis and catabolism are coordinately regulated during tobacco seed development |
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