DNA and Proteins as Tape Measures of Evolution (Campbell Biology)
We are accustomed to thinking of shared traits, such as hair and milk production in mammals, as evidence of shared ancestry. Because DNA carries heritable information in the form of genes, sequences of genes and their protein products document the hereditary background of an organism. The linear sequences of nucleotides in DNA molecules are passed from parents to offspring; these sequences determine the amino acid sequences of proteins. As a result, siblings have greater similarity in their DNA and proteins than do unrelated individuals of the same species.
Given our evolutionary view of life, we can extend this concept of “molecular genealogy” to relationships between species: We would expect two species that appear to be closely related based on anatomical evidence (and possibly fossil evidence) to also share a greater proportion of their DNA and protein sequences than do less closely related species. In fact, that is the case. An example is the comparison of the β polypeptide chain of human hemoglobin with the corresponding hemoglobin polypeptide in other vertebrates. In this chain of 146 amino acids, humans and gorillas differ in just 1 amino acid, while humans and frogs, more distantly related, differ in 67 amino acids. And this conclusion holds true as well when comparing whole genomes: The human genome is 95–98% identical to that of the chimpanzee, but only roughly 85% identical to that of the mouse, a more distant evolutionary relative. Molecular biology has added a new tape measure to the toolkit biologists use to assess evolutionary kinship.
Urry, Lisa A.. Campbell Biology. Pearson Education. Kindle Edition. https://www.pearson.com/us/higher-education/series/Campbell-Biology-Series/2244849.html
Research Article: From Nonspecific DNA–Protein Encounter Complexes to the Prediction of DNA–Protein Interactions
Date Published: April 3, 2009 Publisher: Public Library of Science Author(s): Mu Gao, Jeffrey Skolnick, Ilya Vakser Abstract: DNA–protein interactions are involved in many essential biological activities. Because there is no simple mapping code between DNA base pairs and protein amino acids, the prediction of DNA–protein interactions is a challenging problem. Here, we present a … Continue reading
Research Article: Sliding of Proteins Non-specifically Bound to DNA: Brownian Dynamics Studies with Coarse-Grained Protein and DNA Models
Date Published: December 11, 2014 Publisher: Public Library of Science Author(s): Tadashi Ando, Jeffrey Skolnick, G. Marius Clore Abstract: DNA binding proteins efficiently search for their cognitive sites on long genomic DNA by combining 3D diffusion and 1D diffusion (sliding) along the DNA. Recent experimental results and theoretical analyses revealed that the proteins show a … Continue reading
Research Article: Potency, Efficacy and Durability of DNA/DNA, DNA/Protein and Protein/Protein Based Vaccination Using gp63 Against Leishmania donovani in BALB/c Mice
Date Published: February 2, 2011 Publisher: Public Library of Science Author(s): Saumyabrata Mazumder, Mithun Maji, Amrita Das, Nahid Ali, Jörg Hermann Fritz. http://doi.org/10.1371/journal.pone.0014644 Abstract: Visceral leishmaniasis (VL) caused by an intracellular protozoan parasite Leishmania, is fatal in the absence of treatment. At present there are no effective vaccines against any form of leishmaniasis. Here, we evaluate … Continue reading
Research Article: Predicting Target DNA Sequences of DNA-Binding Proteins Based on Unbound Structures
Date Published: February 1, 2012 Publisher: Public Library of Science Author(s): Chien-Yu Chen, Ting-Ying Chien, Chih-Kang Lin, Chih-Wei Lin, Yi-Zhong Weng, Darby Tien-Hao Chang, Vladimir N. Uversky. http://doi.org/10.1371/journal.pone.0030446 Abstract: DNA-binding proteins such as transcription factors use DNA-binding domains (DBDs) to bind to specific sequences in the genome to initiate many important biological functions. Accurate prediction of … Continue reading