Sp1 transcription factor

Transcription factor Sp1, also known as specificity protein 1* is a is_associated_with::protein that in humans is encoded by the SP1 is_associated_with::gene.

Function
The protein encoded by this gene is a is_associated_with::zinc finger is_associated_with::transcription factor that binds to GC-rich motifs of many promoters. The encoded protein is involved in many cellular processes, including cell differentiation, cell growth, is_associated_with::apoptosis, immune responses, response to DNA damage, and is_associated_with::chromatin remodeling. Post-translational modifications such as phosphorylation, acetylation, glycosylation, and proteolytic processing significantly affect the activity of this protein, which can be an activator or a repressor.

In the is_associated_with::SV40 virus, Sp1 binds to the GC boxes in the regulatory region (RR) of the genome.

Structure
SP1 belongs to the is_associated_with::Sp/KLF family of transcription factors. The protein is 785 is_associated_with::amino acids long, with a molecular weight of 81 kDA. The SP1 transcription factor contains a zinc finger protein motif, by which it binds directly to DNA and enhances gene transcription. Its zinc fingers are of the Cys2/His2 type and bind the is_associated_with::consensus sequence 5'-(G/T)GGGCGG(G/A)(G/A)(C/T)-3' (is_associated_with::GC box element).

Applications
Sp1 has been used as a control protein to compare with when studying the increase or decrease of the is_associated_with::aryl hydrocarbon receptor and/or the is_associated_with::estrogen receptor, since it binds to both and generally remains at a relatively constant level.

Inhibitors
is_associated_with::Withaferin A, a sterodial lactone from is_associated_with::Withania Somnifera plant is known to inhibit Sp1 transcription factor.

Interactions
Sp1 transcription factor has been shown to interact with:


 * AATF,
 * is_associated_with::CEBPB,
 * is_associated_with::COL1A1,
 * is_associated_with::E2F1,
 * is_associated_with::FOSL1,
 * is_associated_with::GABPA,
 * is_associated_with::HDAC1,
 * HDAC2,
 * is_associated_with::HMGA1,
 * HCFC1,
 * HTT,
 * is_associated_with::KLF6,
 * is_associated_with::MEF2C,
 * is_associated_with::MEF2D,
 * is_associated_with::MSX1,
 * is_associated_with::Myogenin,
 * is_associated_with::POU2F1,
 * is_associated_with::PPP1R13L,
 * is_associated_with::PSMC5,
 * PML,
 * is_associated_with::RELA,
 * SMAD3,
 * SUMO1,
 * SF1,
 * is_associated_with::TAL1, and
 * UBC.