Revealing evolutionary constraints on proteins through sequence analysis

Statistical analysis of alignments of large numbers of protein sequences has revealed "sectors" of collectively coevolving amino acids in several protein families. Here, we show that selection acting on any functional property of a protein, represented by an additive trait, can give rise to such a sector. As an illustration of a selected trait, we consider the elastic energy of an important conformational change within an elastic network model, and we show that selection acting on this energy leads to correlations among residues. For this concrete example and more generally, we demonstrate that the main signature of functional sectors lies in the small-eigenvalue modes of the covariance matrix of the selected sequences. However, secondary signatures of these functional sectors also exist in the extensively-studied large-eigenvalue modes. Our simple, general model leads us to propose a principled method to identify functional sectors, along with the magnitudes of mutational effects, from sequence data. We further demonstrate the robustness of these functional sectors to various forms of selection, and the robustness of our approach to the identification of multiple selected traits.Comment: 37 pages, 28 figure

Florence S. Ogden to Mr. Silver 9 April 1959

Personal correspondenc

Florence Ogden to Dr. Silver, 7 October 1959

Personal correspondenc

New Basic Chromosome Numbers For Genera Of Neotropical Ferns

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141121/1/ajb207703.pd

Numerical Relation of Spermatozoa to Sertoli Cells

Non

Florence S. Ogden to Dr. Silver, 18 June 1961

Professional correspondenc

Buy American: An Introspective Look into National Corporate Consciousness

My research is interested in examining product perceptions and the importance of national identity on the marketability on a variety of foreign and domestic consumer products. I am also interested in determining whether the process of globalization has weakened an individual’s sense of national identity and whether that changes their preference for purchasing a foreign and/or domestic product. Primarily, my research question asks whether nationalism influences a product’s marketability. My hypothesis suggests that individual perceptions are heavily influenced by a sense of nationalism and ultimately affects an individual’s decision whether or not to buy a foreign good. To test this hypothesis, I constructed two original surveys that were distributed to university students at two different universities in two separate countries, Wilfred Laurier University in Canada and Georgia Southern University in Georgia, US. From my surveys, I have found that despite the advance of globalization and the integration of markets, it appears that student consumers still tend to identify themselves with products and corporations that they perceived as domestic. When asked, they chose domestic products as a means for reaffirming their national identity