In a process known as photosynthesis , plants apply the vigour of sunlight to produce sugar out of body of water and atomic number 6 dioxide in their leafage . The sugar is enrapture from the leaves to the other parts of the plant life to ply carbon and get-up-and-go for growth and the deduction of storage reserves . Franziska Fichtner , John Lunn and colleagues from the work group of Prof. Dr. Mark Stitt from the Max Planck Institute of Molecular Plant Physiology in Potsdam - Golm , together with scientist from international research institutions , are researching a small molecule that , like insulin in human and animals , baffle wampum metabolism and conveyance and the synthesis of store reticence in plant .
dodge of sucrose synthesis and transport in the foliage and localization of the T6P synthesise protein , TPS1 , in the shoot and root vasculature and shoot tip . © Fichtner
T6P the “ insulin ” of plantsInsulin is a hormone that aid human and other animals to regulate their carbohydrate metamorphosis . After eat sugary or stiff foods , line of descent glucose level rise , trip spillage of insulin . This dissemble as a signal for the muscles and other mobile phone to take up glucose , and for excess loot to be converted to storage reserves in the liver and fatty tissues . When line glucose levels fall , another internal secretion , glucagon , activate the conversion of these storage reserves back into glucose . Together , these two hormones hold an optimum level of glucose in the blood . industrial plant also call for to regulate their sugar metamorphosis , to ensure that they do not starve at night when photosynthesis is not possible , and to make the best utilisation of their carbohydrate provision for ontogeny and procreation . However , industrial plant do not have insulin . So how do they regulate their sugar metamorphosis , raptus and depot ?
How do plant life baffle their sugar balance?Researchers at the Max Planck Institute of Molecular Plant Physiology in Potsdam have been working on solving this riddle for a long time . John Lunn excuse : “ We discovered that a small speck call trehalose 6 - phosphate ( T6P ) play a similar character to that of insulin in human . ” T6P is an intermediate in the synthesis of a lucre called trehalose . Trehalose is found in bacterium , fungi and gloomy animals and is used to carry and store carbohydrate , as well as being a emphasis protectant . Trehalose is also happen in archaic plants , like mosses and algae , where it shares these function with a chemically like sugar - saccharose . During the evolution of higher plants , sucrose became the most common wampum and remove over all the main functions of trehalose . This allowed T6P to evolve a novel role in a process know as ‘ neofunctionalisation ’ . Like the insulin reception to high-pitched blood glucose in animals , T6P levels in plants prove as their sucrose level increase . If the plant life is produce too much sucrose during photosynthesis , rebel T6P in the leaves deviate some of the new specify carbon paper to constituent and amino acids . At night , when sucrose is made from starch reticence , high T6P inhibits starch breakdown if saccharose is being made faster than the industrial plant can expend it for growth . In the growing percentage of the plant , the level of T6P signals how much saccharose is available for growth and aggregation of storage reserve . Franziska Fichtner summate : “ We know that T6P also affects developmental transitions , such as shoot branching and inflorescence , which determine the future sugar requirements of the plant . For exemplar , flowering leads to cum formation , which command sugar and vigour so that the seeds can grow and ripen . ” By link up development to the supply of sugar , T6P helps plants maximize cum take without running out of carbon before germ output is fill in .
Investigating the rule of plant simoleons counterpoise with the help of mutantsThe insulin - corresponding function of T6P in signalling and regulating sucrose grade in plants is now well established . However , elaborated knowledge of how and where T6P signalling operates was lacking . In their article , which has just been bring out in the renowned journal " The Plant Cell " , Dr. Fichtner and her colleague took an important step in answering these questions . T6P is farm by the enzyme trehalose-6 - orthophosphate synthase 1 ( TPS1 for short ) . The function of TPS1 was look into in Arabidopsis thaliana , the mannequin plant of many plant researchers . They used two different approaching to “ give chase ” the TPS1 protein with either a fluorescent or enzymatic mark , allow the location of the protein to be visualized under the microscope . " We were initially very surprised to find that the TPS1 protein is located in specific regions of the leaf where saccharose is move into the phloem , which is the sugar transport system in plants " explain Dr. Fichtner . “ This “ phloem - loading zone ” connects those parts of the leaf where sucrose is made to the growing parts of the plant where saccharose is consumed , and so is a strategically significant site for monitoring how much sugar is being made and how much is being used ” supply John Lunn . The scientists next asked which parts of the TPS1 enzyme are necessary for T6P signal to work correctly . To do this , they modify the TPS1 gene in various elbow room and introduced the qualify gene variants into an Arabidopsis mutant that is unable to grow by rights because it has no TPS1 . Some variants of the TPS1 gene reserve the plants to raise unremarkably , but others did not . These experiment give away that , in gain to the catalytic centre , other parts of the TPS1 protein are needed for T6P point to function properly . Some of these plants can be likened to insulin - deficient diabetic patients , as they are unable to regulate their refined sugar levels correctly . These plants will be used to study in more detail how sugar metabolism is controlled by T6P and why it is so fatal for the plant when this arrangement go faulty .
reservoir : Max Planck Institute of Molecular Plant Physiology
