This could happen if transcription factors in the first milieu are blocked by repressive chromatin marks present in certain cis-regulatory sequences of a gene, but transcription factors in the second milieu, distinct from the first, are able to drive expression by recognizing a different set of cis-regulatory sequences of the gene not affected by repressive chromatin.
These American Buddhists, drawn East in part by a rejection of Gilded Age ostentation, recognized a set of preoccupations like those they knew already — Whitman's vision of a self that could shift and contain multitudes, or Thoreau's secular withdrawal from the race of life.
In reality, however, each TF recognizes a set of sequences, located around a consensus sequence [ 1- 11].
In vascular tissue, Toll-like receptors (TLRs) have important roles in activation of the innate and adaptive host defense against infections, by recognizing a specific but restricted set of patterns of microbial origin (so-called pathogen- or microbe-associated molecular patterns or PAMPs/MAMPs).
Upon infection, microbe-specific immune elicitors, known as microbe-associated molecular patterns (MAMPs), are recognized by a set of so-called pathogen recognition receptors (PRRs) [3], [4].
In addition, SAR also uncovered a second binding site in the histone-binding surface recognized by a set of benzimidazoles.
A model has thus emerged in which 'nonself' sequences, such as those introduced with transgenic DNA, is recognized by a set of piRNAs with some level of antisense complementarity.
For instance, conserved structural features of molecular determinants on pathogens, termed pathogen-associated molecular patterns, such as lipopolysaccharide (LPS), flagellin, peptidoglycans, microbial DNA and bacterial lipoproteins, are recognized by a set of germline-encoded receptors on host cells, the Toll-like receptor (TLR) family [ 5- 8].
