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Glasgow in a knot
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News & Comment
brought on by 0.5 M mannitol treatment in T87 cells (DREB2A, rd29A, rd17, AtP5CS1 and rd20). Neomycin significantly reduces the expression of the genes that contain only a cis-acting element – rd29A and rd17 – termed the dehydration-responsive element (or C-repeat in their promoter). Consequently, the authors propose the involvement of phosphoinositide-turnover in an abscisic acidindependent hyperosmotic-stress signal transduction pathway in higher plants. This is the first study that clearly defines the increase of Ins(1,4,5)P3 as a possible
TRENDS in Plant Science Vol.6 No.9 September 2001
early response to hyperosmotic stress, which supports the hypothesis that Ins(1,4,5)P3 functions in the initial stage of signal-transduction cascades. These results open up a broad area of research: on the one hand to elucidate the involvement of phospholipid catabolism in response to other stresses and on the other hand to unravel the downstream events of Ins(1,4,5)P3 signaling pathways. Information from such investigation could aid in developing plants that can adapt or respond more efficiently to the adverse
environments that are becoming more common throughout the world. 1 Drøbak, B.K. and Watkins, P.A.C. (2000) Inositol(1,4,5)trisphosphate production in plant cells: an early response to salinity and hyperosmotic stress. FEBS Lett. 481, 240–244 2 Takahashi, S. et al. (2001) Hyperosmotic stress induces a rapid and transient increase in inositol 1,4,5-trisphosphate independent of abscisic acid in Arabidopsis cell culture. Plant Cell Physiol. 42, 214–222
Juan M. Ruiz [email protected]
In Brief
Nicotine’s naughty bits
Glasgow in a knot
Nicotine, a secondary compound in tobacco, is not only addictive, but promotes angiogenesis, the formation of new blood vessels. Christopher Heescheen and colleagues [Nat. Med. (2001) 7, 833–839] used human cell lines and mouse model systems to show that nicotine enhances blood vessels in vitro and in vivo. Orally administered nicotine increases vascular growth in fibroblast cells in mice. The vessels are functional and allow blood to flow in them. Tobacco’s siren song also stimulates tumor growth, nearly doubling lung tumor size after 16 days of exposure. The research team also observed that nicotine stimulates plaque formation, which depends on vascularization, in a mouse model of atherosclerosis. The molecular mechanism of nicotine angiogenesis remains to be determined. TS
Mention Japanese knotweed (Reynoutria japonica) in Glasgow (UK) and you will probably get an exasperated sigh. The expatriate has bamboo-like shoots and thrives in shady, damp soils. Over the past few years, the weed has got out of control on the banks of Glasgow’s three rivers, and has colonized a cemetery in the span of one growing season. Knotweed-shootcontaminated soil has the same danger rating as asbestos, according to the city council. The weed breaks through concrete and tarmac, and some houses have the weed growing through floorboards. A spokesman for the city council told reporters that ‘the problem is that no matter what we seem to do, the weed just keeps coming back.’ The weed is even resistant to many common pesticides. Importing natural pests from Japan is being investigated. [Lewis, J. (2001) Evening Times (Glasgow) 13 July, p. 11] TS
New banana ornamental Benchamas Silayoi of Kasetsart University (Thailand) accidentally developed a banana tree that barely reaches the height of a writing pen. Tissue cultures treated with Oryzalin, a herbicide that multiplies plant chromosomes, produced the tiny banana tree, now called BEP. The dwarf has smaller rounder leaves than its original parent, and accumulates stress pigments. Silayoi first publicly displayed the BEP trees last year at the Kasetsart Fair, an agricultural exposition in Bangkok. Silayoi told reporters, ‘the oldest plants are four years old and they still bear no banana blossoms. I hope someday they will.’ Even if the trees bear no fruit, demand for BEP as an ornamental is increasing. (Bangkok Post, 21 June 2001) TS http://plants.trends.com
only known habitat, the Northern Cape plateau of South Africa, by a team from the Millennium Seed Bank in Sussex (UK). ‘Rediscovery’ of this plant, which gets its curious name from its enormous edible tuber, which can weigh up to 300 kg, begs the question of how many other ‘extinct’ species are just waiting to be refound. [New Sci. (2001) 19 May, p. 25] NC
Sudden oak hits tenth species Forest scientists recently identified California buckeye trees (Aesculus californica) as the tenth species infected with Phytophthora, which causes the disease known as sudden oak death. Already, the pathogen has killed tens of thousands of oaks in California and has been found to infect a variety of species such as rhododendron and arrow wood (Viburnum acerifolium). In some counties, 80% of the canopy trees are dead. Matteo Garbelotto, a forest pathologist at the University of California at Berkeley (CA, USA) told reporters that he believes that the pathogen uses other infected species as a launching pad for its spores to spread to oak trees. Ecologists are concerned that oak trees could disappear like the American chestnut tree (Castanea dentata) did nearly a century ago. [Fimrite, P. (2001) The San Francisco Chronicle 2 July, p. A13] TS
Yam today (and yam tomorrow) A structure in search of a function It seems that reports of the demise of elephant’s foot (a variety of Dioscorea elephantipes) are an exaggeration. Although feared extinct for >40 years, the yam has recently been rediscovered in its
Although discovered in the castor oil plant (Ricinus communis) >30 years ago, the ricinosome has only recently been ascribed a function. In spite of its name, it
1360-1385/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.
News & Comment
brought on by 0.5 M mannitol treatment in T87 cells (DREB2A, rd29A, rd17, AtP5CS1 and rd20). Neomycin significantly reduces the expression of the genes that contain only a cis-acting element – rd29A and rd17 – termed the dehydration-responsive element (or C-repeat in their promoter). Consequently, the authors propose the involvement of phosphoinositide-turnover in an abscisic acidindependent hyperosmotic-stress signal transduction pathway in higher plants. This is the first study that clearly defines the increase of Ins(1,4,5)P3 as a possible
TRENDS in Plant Science Vol.6 No.9 September 2001
early response to hyperosmotic stress, which supports the hypothesis that Ins(1,4,5)P3 functions in the initial stage of signal-transduction cascades. These results open up a broad area of research: on the one hand to elucidate the involvement of phospholipid catabolism in response to other stresses and on the other hand to unravel the downstream events of Ins(1,4,5)P3 signaling pathways. Information from such investigation could aid in developing plants that can adapt or respond more efficiently to the adverse
environments that are becoming more common throughout the world. 1 Drøbak, B.K. and Watkins, P.A.C. (2000) Inositol(1,4,5)trisphosphate production in plant cells: an early response to salinity and hyperosmotic stress. FEBS Lett. 481, 240–244 2 Takahashi, S. et al. (2001) Hyperosmotic stress induces a rapid and transient increase in inositol 1,4,5-trisphosphate independent of abscisic acid in Arabidopsis cell culture. Plant Cell Physiol. 42, 214–222
Juan M. Ruiz [email protected]
In Brief
Nicotine’s naughty bits
Glasgow in a knot
Nicotine, a secondary compound in tobacco, is not only addictive, but promotes angiogenesis, the formation of new blood vessels. Christopher Heescheen and colleagues [Nat. Med. (2001) 7, 833–839] used human cell lines and mouse model systems to show that nicotine enhances blood vessels in vitro and in vivo. Orally administered nicotine increases vascular growth in fibroblast cells in mice. The vessels are functional and allow blood to flow in them. Tobacco’s siren song also stimulates tumor growth, nearly doubling lung tumor size after 16 days of exposure. The research team also observed that nicotine stimulates plaque formation, which depends on vascularization, in a mouse model of atherosclerosis. The molecular mechanism of nicotine angiogenesis remains to be determined. TS
Mention Japanese knotweed (Reynoutria japonica) in Glasgow (UK) and you will probably get an exasperated sigh. The expatriate has bamboo-like shoots and thrives in shady, damp soils. Over the past few years, the weed has got out of control on the banks of Glasgow’s three rivers, and has colonized a cemetery in the span of one growing season. Knotweed-shootcontaminated soil has the same danger rating as asbestos, according to the city council. The weed breaks through concrete and tarmac, and some houses have the weed growing through floorboards. A spokesman for the city council told reporters that ‘the problem is that no matter what we seem to do, the weed just keeps coming back.’ The weed is even resistant to many common pesticides. Importing natural pests from Japan is being investigated. [Lewis, J. (2001) Evening Times (Glasgow) 13 July, p. 11] TS
New banana ornamental Benchamas Silayoi of Kasetsart University (Thailand) accidentally developed a banana tree that barely reaches the height of a writing pen. Tissue cultures treated with Oryzalin, a herbicide that multiplies plant chromosomes, produced the tiny banana tree, now called BEP. The dwarf has smaller rounder leaves than its original parent, and accumulates stress pigments. Silayoi first publicly displayed the BEP trees last year at the Kasetsart Fair, an agricultural exposition in Bangkok. Silayoi told reporters, ‘the oldest plants are four years old and they still bear no banana blossoms. I hope someday they will.’ Even if the trees bear no fruit, demand for BEP as an ornamental is increasing. (Bangkok Post, 21 June 2001) TS http://plants.trends.com
only known habitat, the Northern Cape plateau of South Africa, by a team from the Millennium Seed Bank in Sussex (UK). ‘Rediscovery’ of this plant, which gets its curious name from its enormous edible tuber, which can weigh up to 300 kg, begs the question of how many other ‘extinct’ species are just waiting to be refound. [New Sci. (2001) 19 May, p. 25] NC
Sudden oak hits tenth species Forest scientists recently identified California buckeye trees (Aesculus californica) as the tenth species infected with Phytophthora, which causes the disease known as sudden oak death. Already, the pathogen has killed tens of thousands of oaks in California and has been found to infect a variety of species such as rhododendron and arrow wood (Viburnum acerifolium). In some counties, 80% of the canopy trees are dead. Matteo Garbelotto, a forest pathologist at the University of California at Berkeley (CA, USA) told reporters that he believes that the pathogen uses other infected species as a launching pad for its spores to spread to oak trees. Ecologists are concerned that oak trees could disappear like the American chestnut tree (Castanea dentata) did nearly a century ago. [Fimrite, P. (2001) The San Francisco Chronicle 2 July, p. A13] TS
Yam today (and yam tomorrow) A structure in search of a function It seems that reports of the demise of elephant’s foot (a variety of Dioscorea elephantipes) are an exaggeration. Although feared extinct for >40 years, the yam has recently been rediscovered in its
Although discovered in the castor oil plant (Ricinus communis) >30 years ago, the ricinosome has only recently been ascribed a function. In spite of its name, it
1360-1385/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.