Rac and RhoA GTPases coordinate changes in cytoskeleton organization and also through Jun-N-terminal kinase (JNK) regulate gene expression

TLS Online TPP Program

#Id: 8961

#Unit 11. Evolution and Behavior

No matter how it is born, a new gene starts its life as a single copy in the population.

As with any new mutation, by far the most likely outcome is that it will be lost by random drift or selection over the next few generations

TLS Online TPP Program

#Id: 8962

#Unit 11. Evolution and Behavior

Fate of duplicate gene 

TLS Online TPP Program

#Id: 8963

#Unit 11. Evolution and Behavior

If the duplicate is redundant and does not provide a fitness benefit, it will be lost by deletion or the accumulation of loss of-function mutations.

A second fate is that a duplicate can simply retain its original function.

TLS Online TPP Program

#Id: 8964

#Unit 11. Evolution and Behavior

A third fate that can befall a duplicated gene is neofunctionalization. Here the duplicate evolves a novel biological function. 

TLS Online TPP Program

#Id: 8965

#Unit 11. Evolution and Behavior

Most protein-encoding genes, the synonymous rate of change is considerably higher than the nonsynonymous rate because synonymous mutations are tolerated by natural selection

TLS Online TPP Program

#Id: 8966

#Unit 11. Evolution and Behavior

Molecular Variation (Rate) - Which is the number of substitutions taking place per nucleotide site per year