Evolutionary Genetics and Gene Expression Quiz

Study Notes

Stanford University professor made several announcements during a lecture, including absence and confusion about positive selection versus stabilizing selection.
A student in the class has a tattoo illustrating the central dogma of life, sparking excitement and education for those around them.
Two concepts introduced: the gradualism of evolution and the role of DNA as the central dogma of life.
Critique of gradualism and the notion of punctuated equilibrium, where most of the time, nothing exciting is happening in terms of evolutionary shift.
Emphasis on the importance of transcription factors and promoters in gene expression, leading to epigenetic changes.
Attack on DNA as the central starting point and commander of life, revealing that genes are just a readout and most of what happens is environmental regulation of gene activation.
Introduction of epigenetic changes, such as alterations to gene expression that have nothing to do with DNA sequences.
Examples of ways to "futz around" with gene expression, including accessibility of transcription factors to the DNA and permanent changes to accessibility.
Discussion of splicing factors and their role in creating novel proteins through mis-splicing.
Not very often are mis-splice products functional.
Recursive regulation: one splicing factor leads to a big consequence, and a mutation in a promoter can lead to a completely novel network of proteins.
Amplifying effects: major consequences arise from changes in gene expression and protein networks, setting up for potential macroevolutionary changes.- The text discusses the significance of promoters in genes, specifically the vasopressin gene and its promoter.
Vasopressin is a hormone involved in social affiliated behavior in males and is linked to a vasopressin receptor gene.
Different species of voles (a type of rodent) have different promoters upstream of the vasopressin receptor gene.
Monogamous vole species have a different promoter than polygamous ones.
Changing the promoter in a polygamous male vole can convert it into a monogamous one, altering behavior.
Dynorphin, a hormone neurotransmitter related to pain perception, also has a promoter that predicts an organism's susceptibility to drug addiction.
In humans, the version of the vasopressin promoter a person has influences the stability of their social relationships.
Transcription factors are crucial as they control which proteins are expressed and when, and changes in transcription factors can result in macroevolutionary differences.
Barbara McClintock, a plant geneticist, discovered transposable genetic elements, which genes can move around within a genome.
Transposable genetic elements are essential for plants as they cannot escape threats like animals can, so they must have more subtle defenses.
Transposable genetic elements are used to create antibodies in response to new pathogens in animals, including humans.
Trypanosomes, a parasite, can create new surface proteins to avoid being recognized by the immune system, making transposable genetic elements crucial in the evolutionary arms race between the parasite and the host.
In primates, a specific transposable element is most mobile during the production of new neurons, allowing for novel neuron functions.
Inducing movable genetic elements is a common theme in evolution and allows for greater adaptability and novelty.- Transposable events result in genetic variability, both beneficial and detrimental.
Transposable events allow for the movement of DNA segments, leading to macro consequences.
An if/then clause example: if you're dehydrated, tell your kidneys to retain water.
Transposable events can result in the movement of the if/then clause promoter, leading to new gene expression.
Example: an if/then clause promoting ovulation when the dehydration promoter is activated.
Transposable events can lead to the creation of new if/then clauses and rules, such as kin selection.
Transposable events can also result in the movement of gene parts (exons) and the creation of new genes.
Steroid hormones bind to specific receptors and activate corresponding promoters.
Transposable events can result in the transfer of hormone binding domains to new promoters, creating new if/then clauses.
Hormone binding domains and DNA binding domains are located in different exons in steroid receptor genes.
A transposable event can result in a new if/then clause, such as the progesterone receptor suppressing immunity instead of glucocorticoids.
During pregnancy, the suppression of the immune system (progesterone) is a useful adaptation.
After pregnancy, the immune system can overshoot, leading to autoimmune diseases.
Gene duplication and copy number variants can lead to interesting outcomes, such as the duplication of genes related to carbohydrate digestion.
Duplicated genes can function as backups or serve as a basis for faster evolution.
Joe Thornton's research shows that steroid receptor genes were once duplicates that evolved independently.
Duplicated genes can help explain the problem of irreducible complexity in evolutionary theory.

Description

Test your knowledge on evolutionary genetics, gene expression, and the role of transposable genetic elements in evolutionary processes. Explore concepts such as the central dogma of life, epigenetic changes, transcription factors, mis-splicing, and the impact of gene duplication and copy number variants on evolution.