Arabidopsis Sugar Perception Signal Mutation The Body Mig3 Research

Arabidopsis tha/iana is a member of the mustard family (Cruciferae or Brassicaceae) with a broad natural distribution throughout Europe, Asia, and North America. In China it could be found in these provinces such as Inner Mongolia, Xinjiang, Shaanxi, Gansu, Tibet, Shandong, Anhui, Hubei, Sichuan, Yunnan.F. Laibach first summarized the potential of Arabidopsis thaliana as a model organism for genetics in 1943 - he did some work on it much earlier though, publishing its correct chromosome number in 1907. There are lot of advantages with Arabidopsis as a model organism for studies of the cellular and molecular biology of flowering plants The following are the main advantages cited from TAIR database:1. Small genome (114.5 Mb/125 Mb total) has been sequenced in the year 2000.2. Extensive genetic and physical maps of all 5 chromosomes.3. A rapid life cycle (about 6 weeks from germination to mature seed).4. Prolific seed production and easy cultivation in restricted space.5. Efficient transformation methods utilizing Agrohacterium tumefaciem6. A large number of mutant lines and genomic resources.7. Multinational research community of academic, government and industry laboratories. Arabidopsis thaliana has recently become the organism of choice for a wide range ofstudies in plant sciences. The current visibility of Arabidopsis research reflects the growing realization among biologists that this simple angiosperm can serve as a convenient model not only for plant biology but also for addressing fundamental questions of biological structure and function common to all eukaryotes.Sugars such as sucrose, glucose, and fructose have an essential function in plant metabolism. These sugars are important for intermediary and respiratory metabolism and are the substrate for synthesizing complex carbohydrates such as starch and cellulose. Moreover, sugars provide the building blocks for amino acid and fatty acid biosynthesis and essentially all other compounds present in plants. These metabolic processes have long been studied in depth but another aspect of plant sugar biology has recently become the focus of intense research efforts: the signaling function of sugars. Sugars as such can signal alterations in gene expression similar to the concepts developed for hormones.Mutants are important tools to analyze the physiological function of complex sensing and signaling systems. Moreover, mutants allow the study of functional interactions between genes. Importantly, in several plant systems, the technology is now available to clone the relevant genes and study their function. Arabidopsis is being used extensively in sugar sensing research for mutant identification, and several laboratories have established different mutant identification protocols. A mig (mannose insensitive germination) mutant pool, which was created with T-DNA insertion by Kenneth Feldmann, University of Arizona (ecotype Wassilewskija-2, Ws-2), was obtained from the Nottingham ArabidopsisIV 吉林衣业大学博士论文 PhD －Yhesls 摘要 Ah。tractsStock Centre (NASC), UK. mig3 is one line of the mutant pool, which was thought as a putative mutant for having a high germination rate (about 70%) on MS media containing about 5-7.5 mM mannose. Lately, the mig3 was found there are some special characteristics in two French labs by Laurent Signore and Marlire Dieuaide. When germinated and growth under high CO2 mig3 showed an increase in biomass. Freezing tolerance was impaired in mig3 and the roots of mig3 plants were susceptible to sugar starvation. It, therefore, is thought meaningful to find the gene(s) responsible for the mutant, not only helpful to the sugar sensing signal research, but also to Agriculture on crop production in a high CO2 condition.Search for the mig3 gene was going with entailing fine mapping the mutant gene to a small region of the genome by the generation and successive screening of a collection of recombinants. The mutant, therefore, is cro...