Plant Transposable Elements

Transposon tagging can work. Even though most of our understand­ ing about the factors that contribute to a successful tagging experiment has been accumulated from a limited number of experiments using different transposable elements in different genetic backgrounds, it is still possible to draw some conclusions regarding the best experimental strategies for gene tagging. In our experience, Spm has proved to be a good element for transposon tagging. The frequency of recovering mutable alleles in­ duced by Spm is not significantly different from that for Ac-Ds or for Mu 6 (summarized in Ref. 22) and varies from about 10- to 10=zr:-8pm has the unique advantage, however, in that all of the members of thiSfumily that have been examined thus far are homologous to each other at the DNA level. Therefore, by combining molecular analysis with genetic segre­ gation, it is possible to identify and isolate alleles that are due to insertions of either autonomous or nonautonomous Spm elements. There are definite steps one can take to increase the chances of de­ tecting a transposition into the gene of interest. The most important step is to select a genetic background in which the desired phenotype will be easy to screen. If the phenotype is not likely to be mutable, then tester lines should be constructed so as to contain flanking markers that can aid in subsequent segregation analyses. Front Matter....Pages i-xi Positive and Negative Regulation of the Suppressor-Mutator Element....Pages 1-15 Germ Line and Somatic Mutator Activity: Are they Functionally Related?....Pages 17-42 The Mobile Element Systems in Maize....Pages 43-68 Genetic and Molecular Analysis of Transposable Elements in Antirrhinum Majus ....Pages 69-80 Recombinant Mutable Alleles of the Maize R Gene....Pages 81-89 Studies on Transposable Element Ac of Zea Mays ....Pages 91-99 Maize Transposable Elements: Structure, Function, and Regulation....Pages 101-113 Structure and Function of the En / Spm Transposable Element System of Zea Mays : Identification of the Suppressor Component of En ....Pages 115-119 Regulation of Mutator Activities in Maize....Pages 121-135 The Use of Mutator for Gene-Tagging: Cross-Referencing between Transposable Element Systems....Pages 137-147 Advantages and Limitations of Using Spm as a Transposon Tag....Pages 149-159 Transposition of Ac in Tobacco....Pages 161-174 Transposition and Retrotransposition in Plants....Pages 175-187 The Maintenance of Transposable Elements in Natural Populations....Pages 189-212 Deletions and Breaks Involving the Borders of the Ac Element in the bz-m2(Ac) Allele of Maize....Pages 213-226 Transposable Elements of Antirrhinum Majus ....Pages 227-235 The State of DNA Modification within and Flanking Maize Transposable Elements....Pages 237-250 Extrachromosomal Mu ....Pages 251-259 Molecular Characterization of Suppressor-Mutator ( Spm )-Induced Mutations at the bronze-1 Locus in Maize: The bz-m13 Alleles....Pages 261-278 Mutagenesis Using Robertson’s Mutator Lines and Consequent Insertions at the Adh1 Gene in Maize....Pages 279-288 A New Mu Element from a Robertson’s Mutator Line....Pages 289-291 Alterations in Gene Expression Mediated by DNA Insertions in the waxy Gene of Maize....Pages 293-303 Discovery of Ac Activity Among Progeny of Tissue Culture-Derived Maize Plants....Pages 305-315 Activation of Silent Transposable Elements....Pages 317-323 Activation of a Mutable Allele in Alfalfa Tissue Culture....Pages 325-337 Structure and DNA Modification of Endogenous Mu Elements....Pages 339-350 Comparison of Methylation of the Male- and Female-Derived wx-m9Ds-cy Allele in Endosperm and Sporophyte....Pages 351-354 Back Matter....Pages 355-404