L1 - Introduction Flashcards
What are the translational implications of stem cells?
Stem cell therapy Disease modelling Congenital birth defects Ageing related conditions Cancer
What are the 5 stages of early embryonic development?
- Zygote – first diploid cell to arise following fertilisation
- Morula
- Blastocyst
a. Inner cell mass
b. Trophoectoderm – gives rise to extra embryonic tissues
c. Blastocoel – fluid filled cavity - Implantation
- Post-implantation epiblast
What is cell potency?
Ability of a cell to differentiate to other cell types
What are stem cells?
Drivers of both embryonic development and adult tissue homeostasis
Exhibit multiple degrees of potency
What do stem cells have the ability to do?
Undergo self-renewal in a niche
Make one or more different cell types under the influence of specific signals
What are embryonic stem cells?
Pluripotent
In vitro culture – embryonic stem cells = induced pluripotent stem cells
- Can give rise to every single cell of the body
What are the applications of pluripotent stem cells?
Cell replacement therapy
Disease modelling
Drug screening
Modelling embryonic development
What is an example of an adult stem cell?
Intestinal epithelium
- Undergoes constant turnover
- Driven by cells in the intestinal crypt at the base of the villi
- Can also be captured in vitro giving rise to organoids resembling a crypt
What is senescence?
Age related decline in function
What are some factors of senescence?
DNA damage, reactive oxygen species
What is regeneration?
Ability of the fully developed organism to replace organs by growth/repatterning of existing tissue
What is growth and cell division driven by?
Driven by the cell cycle
- Consists of 4 phases
- Resting phase = G0
- Driven by cycling and CDKs
What is an oncogene?
A gene capable of transforming a normal cell into a tumour cell
What is a tumour suppressor gene?
Restrict proliferation
What is one example of an oncogene?
Neuroblastoma – common solid tumour in infants and young children
Aggressive neuroblastomas express high levels of the transcription factor MYCN
What is one example of a tumour suppressor gene?
Normally function in DNA damage/repair and induces cell cycle arrest or apoptosis
Mice with mutation in p53 have higher incidence of tumours
Where do neuroblastomas originate?
Originates in embryonic cell types called neural crest which generates peripheral neurons
What does ectopic overexpression of MYCN lead to?
In normal neural crest cells gives rise to neuroblastoma like tumours
What are pharmacogenetics?
Study of individual gene-drug interactions
Usually one or two genes that have dominant effect on a drug response
What are pharmacogenomics?
Study of genomic influence on drug response
Often using high-throughput data
