fly project begins
DESCRIPTION
Fly Project Begins . Objectives: Organize groups - 4 members maximum Start notebooks - Describe traits and strains, etc. Understand traits and obtain needed flies - Purebreeding Learn about handling flies - Feeding , Anesthetizing Sexing, Virgin collection - PowerPoint PPT PresentationTRANSCRIPT
1
Fly Project Begins
Objectives:Organize groups - 4 members maximum
Start notebooks - Describe traits and strains, etc.
Understand traits and obtain needed flies - Purebreeding
Learn about handling flies - Feeding , AnesthetizingSexing, Virgin collectionSet up stock of each strain
For September 18, obtain 10 virgin females of each strain (wild type,
w sn m e).
2
Inheritance in Drosophila melanogaster
Project
Investigate genes responsible for four traits: white vs. red eyes; miniature vs. normal wings;ebony vs. tan body color, singed vs. normal bristles
Determine:1) Number of genes involved2) If each gene is X-linked or autosomal 3) If the mutant or wild-type allele for each is
dominant4) If genes are linked or assorting
independently5) Map distances between all linked genes
3
Wild-type Drosophila melanogaster
Red eyesLong wings‘Gray/ tan’ bodySmooth bristles
4
Traits Studied
Miniature wings ( m )
Forked bristles ( f )Singed bristles (sn)
+
sn
5
Traits Studied
Scarlet eyes (st)
White eyes (w)
wild type (+)
Brown eyes (bw)
6
Traits Studied
Wild type (+) Yellow bodies (y) Ebony bodies (e)
7
Crosses to be Performed
Reciprocal crosses:
strain A x strain B ; strain A x strain B
F1 x F1 crosses ( F1 female x F1 male ): If all X-linked or independently assorting
Testcrosses ( F1 female x strain A or strain B male ): Mapping
F1 x pure-breeding recessive
8
Finding Information about Traits
9
10
Finding Information about Traits
11
Finding Information about Traits
12
Finding Information about Traits
13
Finding Information about Traits
14
Finding Information about Traits
15
Reasons for Studying D. melanogaster
Small size
Short generation time (10 days - two weeks )
Easy maintenance
Number of well characterized traits 13,601 protein-encoding genes identifiedcomprehensive genetic mapgenome sequencedmany genes comparable to humans
16
Viewing and Anesthetizing Flies
Binocular dissecting microscopesocular focus, zoom
Carbon dioxideanesthetizing needlesanesthetizing platformsTurn off CO2 before leaving lab
MITES!!! Wipe down everything with ethanol (70%)even when not working with
flies
17
Fly Care and Maintenance
Feeding - Instant Drosophila MediumSterile vials and plugs
Transfer flies to new vials with new foodStocks - Every two weeksCrosses - Every 3-4 days, until larvae in
first vials
Incubator 24OC (Room temperature for now)
18
Fly Management and Supply Cleaning
Morgue - unwanted adults -
Freezer - unwanted cultures with potential larvae -
Vial and Plug Washing - thawed vials rinsed with warm water,medium dissolved, brushed from vial,
plugs rinsed with warm water until clean,
19
Sexing Flies
Male Female
20
Sexing Flies
http://www.bio.ilstu.edu/Edwards/other/Sexing_Drosophila.shtml
Sex combs are only seen in males
21
Sexing Flies
http://www.bio.ilstu.edu/Edwards/other/Sexing_Drosophila.shtml
Genital arch in males
22
Sexing Flies
Male Female
23
Life Cycle
Pupae Eggs
Larvae
24
Life Cycle
25
Virgin Collection
Adults emerge from pupal cases (eclose)Males not ready to mate for 8-10 hrFemales ready immediately
Clear Vials before 9 AM
Return within 8 hours
Separate males and females into separate vials
26
Lab Supplies and Access
Main Lab
Tour of Fly Room
Key Pad - 3334
27
Before Leaving Lab Tuesday
Everyone in group must know how to:
feed, transfer, anesthetize flies
distinguish mutant traits from wild type
collect virgins
Plan - who will find information about each trait;
times when each member will be in lab to clear, etc.
By September 18 - Make sure you have 10 virgin females from each strain and 10 males from each strain for reciprocal crosses, which will be set up in lab.