(Usseek.com, 2016)

PRESENTED BY:

LAW CHOON YIK

SATHIAVANI

TAN KIAN LEONG

WONG CHING YEE CHRISTIN (0322752)

INTRODUCTION

Knock-in is targeted, meaning the

desired gene is inserted into a specific

locus in the target genome via

homologous recombination (Cureffi,

org, 2016)

Figure explaining the process of knock in and knock out

in mouse model (Kumar & Sahal, 2016)

A gene knock-in can be seen as a gain of

function mutation.

One example of Gene knock in mouse,

are the humanised mouse models.

Advantages of Humanized Mouse

Model

1. Mimic human pathological

conditions

2. Conduct preclinical research

3. Test compound efficacy

4. Measure compound’s effects on

human proteins (Genoway.com, 2016)

INTRODUCTION

Figure explaining differences between wild type mouse and Humanized Mouse (Genoway.com, 2016)

INTRODUCTIONALZHEIMER’S DISEASE

Alzheimer’s is a progressive disease

which cause progressive brain damage,

causing problems with memory,

thinking and behavior.

DISEASE PROGRESSION

Proteins build up in the brain to form

structures called plague and tangles.

This leads to the loss of connections

between nerve cells and eventually

causing the death of nerve cells and loss

of brain tissue

Patients will have shortage of chemical

messengers which is important for

transmitting signals around the brain.

Figure showing effects of Alzheimer’s disease to brain of patient

(Prezi.com, 2016)

APPLICATION

APPLICATION OF KNOCK IN MOUSE MODEL

It is use as models for a variety of studies which includes, human disease, target protein

expression, and cell trafficking.

GENE KNOCK IN FOR ALZHEIMERS DISEASE

Mutations in the amyloidprecursor protein gene leading to a production of excess amyloid β-peptide (αβ) is believed to be a main contributor to the dysfunction and degeneration of neurons that occurs in Alzheimer’s disease.

Figure showing the various mutation to APP gene affecting the different type of

Secretase (Bassit, Chau, Ming Li, and Tian, 2009)

APP mutations are located in exons 16

and 17, where they cluster primarily

around the secretase processing sites.

There are genes coding for β-, α-, γ-

Secretase within the APP gene.

For Example, mutations near the β-

secretase site, augment β-secretase

cleavage and increase general α β

levels, which leads to excess

production of amyloid peptide.

(Wiki.iop.kcl.ac.uk, 2016)

For study of Alzheimer’s Disease,

Mouse with overexpression of mutant

APP is generated.

APPLICATION

Figure showing the various mutation to APP gene affecting the different type of

Secretase (Bassit, Chau, Ming Li, and Tian, 2009)

Study of Alzheimer’s Disease in Mouse Model

Mouse with Swedish

Mutation

Mouse with Swedish

and Iberian Mutation

Mouse with Swedish,

Iberian and Arctic Mutation

NORMAL

α β deposition in the

cortex and

hippocampus at 6th

month

Memory impairment

at 11th Month

Accelerated α β

aggregation starting at

2nd month

Memory impairment

at 6th month.

(Mus. brc.riken.jp, 2016),

(medicalxpress.com, 2016)

APPLICATION

RESULT

Both mutation group, (Swedish And

Iberian Mutation) And ( Swedish,

Iberian, and Artic Mutation), the mice

are found to have typical α β

pathology,

Neuroinflammation, and memory

impairment (Mus. brc.riken.jp, 2016).

IMPLICATION

IMPLICATION

Various type of different mutation in the

Amyloid Precursor Protein (APP) gene can

contribute to Alzheimer’s Disease causing

its plagues and tangles formation,

degeneration of brain tissue.

The symptoms from the mouse also

matched with the symptoms from

Alzheimer’s patients.

Figure showing the effects of mutation of APP gene to mice (Mus. brc.riken.jp, 2016)

Potential Challenges in this study

1. The mouse usually over expresses the α β expression compared to a normal human which makes the Alzheimer studies hard to be compared to a human Alzheimer (Elder, Gama Sosa & De Gasperi, 2010).

2. Despite similarities between mouse and human brain, it can be challenging to draw definitive parallels between cognitive function in humans and mouse models (Oapublishinglondon.com,2016).

CHALLENGES

(Clipartpanda.com, 2016)

- Lack of progressive model

- Limited translation of preclinical findings

- Outcome measures may not be relevant to human disease

- High label-license costs

- Inability to compare results across experiments and laboratories

-Lack of standardization in outcome measures and varying methodologies (Marco

et.al, 2013).

Challenge of Knock In Mouse Model

-Mouse physiology is not the same as

humans

-Proteins expressed may not be expressed

the same as the human expression of the

same protein

Knock in gene makes mouse model too

complex.

- Which may lead to side effects and

unexplainable phenotypes

CHALLENGES

(The gramMarch Challenge, 2016)

-Knock In Mouse Model is a good strategy to

study for variety of human diseases, targeted

protein expression.

-This model have been used to study for other

diseases such as Huntington Disease and Dilated

Cardiomyopathy.

-Due to this model, scientist could deduce that

the accumulation of amyloid peptide is the

contribution to Alzheimer’s Disease.

-More effective treatment and possibly drugs can

be produced based on the studies done.

CONCLUSION

Figure depicting the disorder in movement due to

Hungtington’s Disease ( Browning and Browning, 2016)

Figure showing chest radiograph of a child with idiopathic

dilated cardiomyopathy (emedicine.medscape.com, 2016)

Bassit, B, Chau, D, Ming Li, Y and Tian, Y. (2009) An APP inhibitory domain containing the Flemish mutation residue modulates y-secretase activity for AB production. Nature Structural & Molecular Biology. [online] Available at: http://www.nature.com/nsmb/journal/v17/n2/full/nsmb.1743.html [Accessed 20 Oct. 2016].

Browning, K. and Browning, K. (2016). The disorderly dance: Huntington's Disease | Read About This. [online] Read About This. Available at: http://read-about-this.com/huntingtons-disease-the-disorderly-dance/ [Accessed 20 Oct. 2016].

Clipartpanda.com. (2016). Challenge Clipart | Clipart Panda - Free Clipart Images. [online] Available at: http://www.clipartpanda.com/categories/challenge-clipart [Accessed 20 Oct. 2016].

Cureffi.org. (2016). The difference between knock-in and transgenic mice. [online] Available at: http://www.cureffi.org/2012/11/13/the-difference-between-knock-in-and-transgenic-mice/ [Accessed 20 Oct. 2016].

Elder, G., Gama Sosa, M. and De Gasperi, R. (2010). Transgenic Mouse Models of Alzheimer's Disease. Mount Sinai Journal of Medicine: A Journal of Translational and Personalized Medicine, 77(1), pp.69-81.

Emedicine.medscape.com. (2016). Pediatric Dilated Cardiomyopathy: Practice Essentials, Background, Pathophysiology. [online] Available at: http://emedicine.medscape.com/article/895187-overview [Accessed 20 Oct. 2016].

Genoway.com. (2016) Humanized Mouse Model. [online] Available at: https://www.genoway.com/services/customized-mouse/knockin-models/humanisation.htm [Accessed 20 Oct. 2016].

Hall, B., Limaye, A. and Kulkarni, A. (2009). Overview: Generation of Gene Knockout Mice. Current Protocols in Cell Biology.

Kumar, V And Sahal, D. (2016). Genetic Engineering. [online] Available at: https://www.researchgate.net/figure/292262701_fig25_Figure-26-Genetic-mouse-models-A-Transgenic-mice-are-generated-by-pronuclear-injection [Accessed 20 Oct. 2016].

Marco, A, et.al. (2013) A strategy for the generation, characterization and distribution of animal models by the Michael J. Fox foundation for Parkinson’s research (2013) Special Article, 6(6), pp. 1316–1324. doi: 10.1242/dmm.011940.

Medicalxpress.com. (2016). New mouse model could revolutionize research in Alzheimer's disease. [online] Available at: http://medicalxpress.com/news/2014-04-mouse-revolutionize-alzheimer-disease.html [Accessed 20 Oct. 2016].

Mus.brc.riken.jp. (2016). September 2014 App knock-in mouse strains: new models for Alzheimer’s disease « Experimental Animal Division (RIKEN BRC). [online] Available at: http://mus.brc.riken.jp/en/mouse_of_month/sep_2014_mm [Accessed 20 Oct. 2016].

Oapublishinglondon.com. (2016). Dementia in mouse models of neurodegeneration.OA Neurosciences. [online] Available at: http://www.oapublishinglondon.com/article/1261 [Accessed 20 Oct. 2016].

prezi.com. (2016). Gene Mutation Defends Against Alzheimer's Disease. [online] Available at: https://prezi.com/tuzgjzaxcndb/gene-mutation-defends-against-alzheimers-disease/ [Accessed 19 Oct. 2016].

The gramMarch Challenge. (2016). Home. [online] Available at: http://www.grammarch.org/ [Accessed 20 Oct. 2016].

Usseek.com. (2016). mouse model images - usseek.com. [online] Available at: http://www.usseek.com/images/mouse-model [Accessed 19 Oct. 2016].

Wiki.iop.kcl.ac.uk. (2016). APP mutations. [online] Available at: http://wiki.iop.kcl.ac.uk/default.aspx/Neurodegeneration/APP%20mutations.html [Accessed 20 Oct. 2016].

REFERENCES