The climbing assay

Download Report

Transcript The climbing assay

The University
of Manchester
The climbing assay:
Faculty of
Life Sciences
Learning data analysis through live
experiments with fruit flies..
..reflecting contemporary research into
ageing and neurodegeneration
If you find this resource helpful and integrate (part of) it into your teaching, please, let us
know by sending an informal email to: [email protected]
Starter task
What are they?
How are they different?
Why are they different?
Starter task
They are Fruit Flies (Drosophila melanogaster).
• Females are slightly larger
• Females display dark serrated stripes at the posterior abdomen;
stripes are merged in males
• Only males possess sex combs.
Learning outcome of this lesson
By the end of the lesson I will have…
• ... learned to organise data into tables and graphs.
• ... learned to interpret data trends.
• ... have understood the importance of sample size.
• ... have learned about ..
 .. concepts of ageing
 .. concepts of neurodegeneration
 .. principles of nervous system function
Introduction to the history & importance of Drosophila
https://www.youtube.com/watch?v=qDbJnFLl3kU
What can you remember?
1. What is the scientific name for Fruit Flies?
2. How many Nobel prizes have Fruit Flies contributed to?
3. Where did Fruit Flies originate from?
4. When did Fruit Flies supposedly enter America?
5. Who used Fruit Flies to first demonstrate a link between
Mutation, Genes, Chromosomes and Inheritance.
6. How many flies can you keep on a few lab trays?
7. How quickly do flies become ‘Grandparents’?
8. True or False – Humans and Fruit Flies share many of the
same genes.
Why the fly?
cheap
small
breed rapidly
less legal &
ethical issues
shared biology
with humans
75%
9. Name at least 7 areas of
research that Fruit Flies
currently contribute towards.
Ageing and Mobility
What happens to our ability
to move as we get older?
Assessing motor skills of old versus young
One vial (without mark):
young flies
Other vial (no mark):
old flies
(<1 week; teenagers)
(≥5 weeks; grandparents)
How to carry out the experiment
Carry out & document your experiment: tap flies to bottom, let them climb up
for 15 seconds, take a picture in front of the scale
How to carry out the experiment
Analyse your data: enter numbers of flies in each of the height areas
1-10 for both sides, respectively
Now perform the experiment
Your hypothesis: I predict that
older flies will …
Carry out the experiment
(in parallel look at the activity sheet)
Now plot your data
Plot your results
6 7
5
4
3
2
0 1
Number of flies
8
9 10
Fly distribution across height segments
0
1
2
3
4
5
6
7
Height segments
Old flies
Young flies
8
9
10
Collect data across the course
your own plot
data of all groups
Conclusion of the experiment
• What is the outcome?
• Why do older flies do less well than
younger flies on the climbing assay?
Ageing and muscle degeneration
• Our muscles
degenerate as we age.
• This affects our ability
to jump high, run fast
and lift heavy objects.
Peak Strength
BUT why do
some young
people have
mobility issues?
All organs and
systems in the body
undergo age-related
degeneration
Age
The problem is not with his muscles!
Why can’t Professor Hawking move?
What controls our muscles?
The importance of the nervous system for motor behaviours
Brain
Spinal cord
nerve /
muscle
We often do not understand
why neurons become
dysfunctional.
Drosophila research provides
means to fill this knowledge
gap!
What happens if
motor neurones
are damaged or
lost?
Drosophila and Motor Neurone Disease
Fruit Flies to the rescue!
Bringing a ‘MND gene’ into flies damages
their motor nerves.
CLI MB I N G A SSAY
Wild Type
SOD1
1
0.9
Cl i mbing Index
Drosophila has motor
neurons just as humans.
0.8
0.7
0.6
How would they perform
in the climbing assay?
These assays with MND flies can
be used to find genes &
mechanism explaining the disease,
or drugs to treat it!
0.5
D AY 1
D AY 7
D AY 1 4
D AY 2 1
Age of fl ies
Adapted from: Watson et al 2008
D AY 2 8
Alternative or additional
example of application:
Parkinson's Disease research
(for explanations see the notes below slides)
Drosophila in Parkinson's disease research
• In Parkinson's Disease, primarily nerve cells in the
midbrain (substantia nigra region) are being lost.
• these neurons contain the neurotransmitter
Dopamine and are important for motor coordination.
Paul de Saint-Leger (1879)
Studying Parkinson's in Drosophila
normal
plus α-synuclein
modified from: Feany & Bender (2000)
Bringing a "Parkinson gene" into the fly brain,
selectively kills dopamine nerve cells
modified from: Mao & Davis (2009)
There are
dopamine nerve
cells in the fly brain
These "Parkinson
flies" lose climbing
abilities earlier than
control animals
These assays are
being used to
search for
Parkinson-relevant
genes
modified from: Feany & Bender (2000)
Homework Task
Complete the worksheet provided
Plenary
1) Use bullet points to list what you did and what you learnt
in this lesson.
2) What did you find most difficult to understand during
today's lesson?
3) How would you explain these points to your class mates?
Acknowledgements
If you find this resource helpful and integrate (part of) it into your teaching, please, let us
know by sending an informal email to: [email protected]
This resourse was generated by Patrick Strangward in the
context of a BBSRC-funded internship for PhD students
School supervision and teacher support was provided by
Catherine Alnuamaani, Trinity Church of England High School,
Manchester, UK
Academic, design & Drosophila-specific support was provided
by Andreas Prokop and Sanjai Patel, Faculty of Life Sciences,
The University of Manchester, UK
Note that this resource was developed for the UK key stage 3 school level, but can easily be
adapted to higher levels. Support documents for this teaching resource can be downloaded here:
dx.doi.org/10.6084/m9.figshare.1352064