Sp1 (I18) Antibody from MyBioSource.com

The Sp (specificity protein) family is a family of transcription factors that bind to cis-elements in the promoter regions of various genes. Members of the family bind with varying affinities to sequences designated as 'Sp1 sites' (e.g. GC-boxes. CACCC-boxes. and basic transcription elements) (4.8). In human cells. telomerase activity is tightly regulated by the expression of human telomerase reverse transcriptase (hTERT). Sp1 and Sp3 have been shown to associate with the hTERT promoter. recruiting histone deacetylase for the localized deacetylation of nucleosomal histones and transcriptional silencing of the hTERT gene in normal human somatic cells (3). The role of the Sp family members in many diseases is being investigated. Sp-1 has been discussed in association with diabetic microvasculopathy and Huntington's disease (2.5). It has been suggested that transcription of the Sp3 gene is blocked in immune cells from most patients with multiple sclerosis and that this contributes to the development of central nervous system inflammation in the disease (6). Sp3 has also been shown to be required for proper skeletal ossification (7). Down-regulation of the transcription factor Sp-1 is thought to be involved in the inhibition of strain-induced mitogenesis in human vascular smooth muscle cells by estrogen via an estrogen receptor mediated process (1).