IDPs puts the final nail in the NeoDarwinian SSFP hypothesis

Neo-Darwinism is a modern synthesis of Darwin's theory of evolution by natural selection and Mendelian genetics. It states that the genetic variation that drives evolution is caused by mutations, which can be inherited from parents to offspring. These mutations can change the amino acid sequence of a protein, which can in turn change its three-dimensional structure and function.

The sequence–structure–function paradigm (SSFP) is the idea that the amino acid sequence of a protein determines its three-dimensional structure, and its three-dimensional structure determines its function. This means that changes in the amino acid sequence can lead to changes in the three-dimensional structure, and changes in the three-dimensional structure can lead to changes in the function.

Neo-Darwinism relies on the SSFP because it is the mechanism by which genetic variation can lead to changes in function. If the SSFP did not hold true, then mutations would not be able to change the function of proteins, and therefore could not drive evolution.

The SSFP is essential to understanding how neo-Darwinism works. 

The SSFP was thought to provides a way to link genetic variation to phenotypic variation. Phenotypic variation is the observable differences between individuals, such as their size, shape, and behavior. The SSFP and neodarwinism states that genetic variation can lead to changes in protein function, which can in turn lead to changes in phenotype.

The SSFP was thought to explain how natural selection can act on genetic variation. Natural selection is the process by which organisms with favorable traits are more likely to survive and reproduce than organisms with unfavorable traits. The SSFP states that natural selection can act on genetic variation that affects protein function. This is because changes in protein function can have a direct impact on an organism's ability to survive and reproduce.

The SSFP is a central tenet of Neo-Darwinism, which states that the sequence of a protein determines its structure, which in turn determines its function. However, intrinsically disordered proteins (IDPs) do not fit this paradigm. IDPs are proteins that lack a well-defined three-dimensional structure, and their function is not determined by their sequence alone.

Only recently have scientists discovered that the majority (51%) of human proteins are IDPs. This number is expected to increase in fact scientists believe all proteins have some level of intrinsic disorder to function.

There are several ways in which IDPs disprove neo darwinism and SSFP. First, IDPs can have multiple different structures, depending on their environment. This means that their sequence does not uniquely determine their structure as with neodarwinism. Second, IDPs can have multiple different functions, even though they have the same sequence. This means that their structure does not uniquely determine their function. Third IDP can have more mutations without changing their function. In fact phylogenetic studies have found billion year old IDPs with conserved function. A billion years of no evolution. This violates the NeoDarwinian gradualistic mutation model as with IDPs they have more mutations with no change in function over billions of year's. 

The existence of IDPs challenges the NeoDarwinian understanding of how proteins function and evolve. It shows that the SSFP is incorrect. Instead the function of a protein is determined by a combination of factors, including IDPs and environment.

The discovery of IDPs has led to a rethinking of the SSFP and neodarwinism. It is now clear that this paradigm is not accurate, and that there are other factors that can influence protein structure and function.

Here are some specific examples of how IDPs violate the SSFP:

  • Some IDPs have multiple functions, even though they have the same amino acid sequence.

  • Some IDPs can change their function depending on their environment.

  • Some IDPs can interact with other proteins to form a functional complex, even though they do not have a well-defined structure on their own.

The discovery of IDPs has made it clear that the neodarwinian SSFP is no longer accurate.

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