L. Gold (source code)
= L. Gold
{c}
= Larry Gold
{c}
{synonym}
\b[L. Gold], also published as \b[Larry Gold], is a molecular biologist associated with the development of <SELEX>, a method of repeated selection and amplification of nucleic-acid <ligands>. Gold's own retrospective connects the abbreviated 1990 byline with the work carried out with <Craig Tuerk> at the University of Colorado.<SELEX: How It Happened and Where It will Go by Larry Gold>[Byline and The First Moments]{ref} His university profile also documents the laboratory's bacteriophage research and identifies him as Larry Gold.<Larry Gold profile by the University of Colorado Boulder>[Profile and laboratory history]{ref}
The 1990 primary experiment randomized eight positions in an <RNA> region interacting with a <DNA polymerase>. Repeated binding selection and amplification recovered two sequences with equivalent binding constants, including a variant differing from the original at four positions.<Systematic evolution of ligands by exponential enrichment: RNA ligands to bacteriophage T4 DNA polymerase by C. Tuerk and L. Gold>[Abstract, randomized region and selected-sequence comparison]{ref} This showed that sequence variation could be explored experimentally through measured molecular function.
The distinction between enrichment and absolute yield is important. In an original two-class example, begin with 1,000 desired molecules and 99,000 others. Suppose one selection retains 20% of the desired class and 1% of the others. There are then 200 desired and 990 other molecules: the desired fraction rises from 1% to $200/1190\simeq16.8\%$, even though most desired molecules were lost. Equal amplification of both surviving classes restores material without changing that fraction.
Thus a selection cycle can improve population composition while decreasing the absolute number of every class. Amplification makes another round possible; it does not retrospectively recover a sequence lost completely. This explains the experimental importance of both discrimination and population survival when interpreting <in vitro selection>.
Gold's firsthand account situates the work in a change of perspective: functional <RNA> can be investigated as a folded binding molecule rather than only as an information carrier.<SELEX: How It Happened and Where It will Go by Larry Gold>[The First Moments]{ref} Selection provides evidence about performance under the assay conditions; an <aptamer> recovered there still requires separate characterization for another environment.
\Image[https://www.colorado.edu/mcdb/sites/default/files/styles/large_image_style/public/people/gold_img_7232_800x1000.jpg?itok=kQSl5JFO]
{title=Larry Gold in his University of Colorado molecular biology portrait}
Back to article page
