IMMEDIATE EARLY GENES IN SENSORY PROCESSING, COGNITIVE PERFORMANCE AND NEUROLOGICAL DISORDERS

Immediate early genes (IEGs) are a class of genes that are rapidly expressed without new protein synthesis and, in most cases, in direct response to synaptic input. The most widely studied IEGs in neurobiology encode transcription factors, with two popular examples being c-fos and NGFI-A (a.k.a., zif268 , egr-1, krox-24 and zenk). The activity-dependent expression of most inducible transcription factors has enabled neuroscientists to use their expression as mapping tools for neuronal activation, thereby enhancing our understanding of the anatomical and functional organization of the central nervous system (CNS). IEGs, however, are known to encode not only transcription factors, but a much wider variety of proteins including signaling molecules, growth factors and cytoskeletal proteins. IEGs are therefore both directly and indirectly implicated in the dynamic functional and anatomical restructuring of the CNS that permits the rapid integration of new sensory experience with pre-existing or on-going neural function.