F

Pushin gThe Theory and Practiceof Drosophila Genetics

SECOND EDITION '

Ralph J . Greenspan

Preface, xi

Frequently Used Markers, xi v

Introduction

1

CHAPTER 1The Basics of Doing a Cross, 3

FLY CHROMOSOMES, 3

RECOGNIZING MARKERS, 6

NOMENCLATURE, 7

EVOLUTION OF GENE NAMES, 1 3

WHAT MAKES FLIES SO GREAT? BALANCER CHROMOSOMES, 1 3

DECIPHERING MATING SCHEMES, 1 5

BASIC FLY HUSBANDRY, 1 8

CODDLING DIFFICULT STRAINS, 20

COLLECTING FLIES FOR CROSSES, 21

CHAPTER 2Isolating New Variants, 25

Principles, 2 5

MUTAGENS, 27Ethylmethanesulfonate, 2 7Ethylnitrosourea, 2 8Radiation, 29

Insertional Mutagenesis, 2 9GENETIC SCHEMES FOR DETECTING MUTANTS, 3 1

New Alleles at an Autosomal Locus, 3 1New Alleles on the X, 3 3Identifying New Genes by Mutagenesis, 3 6

Isogenizing the Starter Stock, 36The Mutagenesis Screen, 37Screening the X for New Genes, 40

Insertional Mutagenesis and Enhancer Trapping, 4 1Enhancer-trap Screens, 42New Insertional Alleles of Known Loci, 4 5

Mutating Genes for Which There Are No Allelic Differences, 4 5Screening Over a Deletion of the Locus, 4 5Targeted Insertional Mutagenesis, 4 6

Homologous Recombination, 4 6RNA Interference, 50Searching for Gain of Function, 5 0Generating Mutants : One Size Does Not Fit All, 5 1

CHAPTER 3Mapping, 53

SEGREGATION ANALYSIS, 54Problems with Balancers, 5 5

MEIOTIC MAPPING, 5 7DELETION MAPPING, 6 1DUPLICATION MAPPING, 6 2SYNTHESIZING DELETIONS AND DUPLICATIONS, 63

Identifying New Embryonic Genes by Deletion Mapping, 6 6MAPPING P-ELEMENT INSERTION SITES, 6 9FINE-GRAIN TRADITIONAL MEIOTIC MAPPING WITH P-ELEMEN T

MARKERS, 6 9MAPPING BY P-ELEMENT-INDUCED MALE RECOMBINATION, 7 1FINE-GRAIN MAPPING BY TRANSPOSON-INDUCED

DELETIONS, 73MAPPING BY DNA POLYMORPHISMS, 74

CHAPTER 4Synthesizing Specific Genotypes, 77

Principles, 77

SIMPLE MANIPULATIONS OF A SINGLE CHROMOSOME, 7 8Linking Mutations, 7 8

MANIPULATING TWO CHROMOSOMES, 8 1Pitfalls, 8 5

How Many Flies?, 85Which Sex?, 85

MANIPULATING THREE CHROMOSOMES, 8 7

MAKING REARRANGEMENTS, 88Inducing Deletions, 8 9Synthesizing Stable Deletions from T(YA)s, 92Synthesizing Deletions from P-element Insertions, 9 3Inducing Duplications, 9 5Synthesizing Stable Duplications from T(Y,•A)s, 9 6Synthesizing Attached-Xs, 98Autosynaptic Chromosomes and the Joys of Gibberish, 9 9

-CHAPTER 5Analysis of Mutations : I . Characteristics of the Allele, 10 1

FORMAL CLASSIFICATION OF MUTATIONS, 101Principles, 10 1Null Alleles (Amorphs), 10 2Hypomorphs, 10 3Hypermorphs, 106Neomorphs, 106Antimorphs, 10 7Gain Versus Loss of Function, 10 8Intragenic Interactions, 10 8

INTERACTING LOCI, 10 9Ordering Genes in a Pathway, 11 0Dosage-dependent Interactions, 112

CONDITIONAL ALLELES, 11 3Inducible Promoters, 11 5

MAINTENANCE OF MUTANT PHENOTYPES, 11 7GENETIC BACKGROUND, 118

CHAPTER 6Analysis of Mutations : II . Mosaics, 121

Principles, 12 1

CHROMOSOME LOSS, 122Uses of Chromosome Loss Mosaics, 123

Fate Mapping, 123Focus of Gene Action, 12 4

Methods for Inducing Chromosome Loss, 125Ring Loss, 125Chromosome Loss Mosaics for Autosomal Genes, 12 7paternal-loss (pal), 128claret-non-disjunctional (ca" d ), 129

Care of Mosaic-producing Stocks, 13 0MITOTIC RECOMBINATION, 130

Synchronizing Age of Cultures, 13 3Uses of Mitotic Recombination Mosaics, 13 4

Lineage Analysis, 134Focus of Gene Action, 135Time of Gene Action, 13 6Methods for Producing Mitotic Recombinant Clones, 13 8

Markers for Internal Tissues, 14 0

GAL4 AND EXPRESSION MOSAICISM, 14 0

CELL ABLATIONS, 14 2GAL4 TARGETED FLP/FRT RECOMBINATION, 142

Isolating Tissue-targeted Mutations Using Mitotic Recombination, 14 4P-element Replacement for Exploitation of Existing Enhancer Traps, 14 5

CHAPTER 7Commencement, 147

Solutions to Problems, 14 9

Glossary, 15 9

Appendix : Fly Resources, 16 1

References, 17 1

Index, 183