Systems biology Flashcards
True or false: genotype can refer to only one gene
True
- Genotype can refer to only one gene, or all the genes in a genome
- Genotype: gene(s) inherited by an organism
What are the two things that result in phenotypic variation (what makes individuals different from each other?)
- Different alleles (slight variation in gene sequence results in changes in amino acid sequence of proteins.
- Differential regulation of gene and protein expression (deep blue eyes vs. light blue eyes)
Why do identical twins have slight differences in phenotypes?
Due to epigenetics
- Chromatin packing, nothing to do with nucleotide sequence
- More histones (packed chromatin)= gene silencing and vice versa
Every cell in an organism has an identical genome (DNA sequence). How do different cell types exist?
Due to regulation of which genes are being turned on and off
If we can control tissue-specific transcription, then it is possible for transdifferentiation (changing one tissue into another type of tissue). What are some applications of this?
Regenerative medicine (e.g. making skin grafts for burn victims)
True or false: Macromolecules work individually in a cell to carry out cellular processes
False. Cellular processes involve the concerted action of macromolecules.
If a protein was missing in a ribosome complex (or any protein complex), would the complex remain functional?
Probably not, every protein is usually required in a complex (because these macromolecules are dependent on each other).
How do extracellular stimuli/hormones communicate to genes?
By signal transduction pathways.
What do the the signal transduction pathway components include?
Ligand, cell surface receptor, kinase cascade, transcriptional regulator
What do signal transduction cascades ensure?
Proper gene expression or physiological response from stimulus.
What 4 things are needed to fully decipher and understand how life works?
- Identify all the parts/macromolecules in the cell/organism (nucleic acids, proteins, lipid, metabolites)
- Measure the abundance and dynamics of each macromolecule
- Determine the regulation (multiple levels) and function of each macromolecule (i.e. how does a cell know when to turn a gene on and off?)
- Determine interactions between macromolecules and their biological significance.
Why do we sequence genomes?
To understand how the types and abundance of RNA and proteins result in a phenotype of an organism.
What is systems biology?
The study of an organism (or cell), viewed as an integrated and interacting network of genes, proteins and biochemical reactions which give rise to life.
Describe the systems biology approach
The approach is to analyze all the components (e.g. genes, mRNA and proteins) and their interactions at once to obtain a systems view of a cell/organism (opposite of reductionism)
What is reductionism?
When scientists study one or two components (e.g. their favourite genes)
What was the systems biology field driven by?
This recent field of science was driven by the human genome sequence project and the development of high-throughput technologies to monitor global levels of molecules and interactions simultaneously in a cell.
What are some potential benefits of a system understanding of a cell/organism?
Health, agriculture, ecology, environment.
What four components are needed for a system-level understanding?
- Systems Structures
- System Dynamics
- System Control
- System Design
Describe the systems structures component
What is the parts list?
- Macromolecules: Genes, RNA, proteins, lipids, metabolites
- Macromolecular interactions (e.g. transcriptional regulation, protein binding and biochemical activity)