Sp1, also known as Specificity Protein 1, is a human transcription factor

Transcription factor

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow of genetic information from DNA to mRNA...

 involved in gene expression in the early development of an organism. It belongs to the Sp/KLF family

Sp/KLF family

The Sp/KLF family is a family of transcription factors, including the Kruppel-like factors as well as Sp1, Sp2, Sp3, Sp4, Sp8, Sp9; and possibly Sp5 and Sp7. KLF14 is also designated Sp6....

 of transcription factors. The protein is 785 amino acids long, with a molecular weight

Molecular mass

The molecular mass of a substance is the mass of one molecule of that substance, in unified atomic mass unit u...

 of 81 kDA. The SP1 transcription factor contains a zinc finger protein

Zinc finger

Zinc fingers are small protein structural motifs that can coordinate one or more zinc ions to help stabilize their folds. They can be classified into several different structural families and typically function as interaction modules that bind DNA, RNA, proteins, or small molecules...

 motif, by which it binds directly to DNA and enhances gene transcription. Its zinc fingers are of the Cys₂/His₂ type and bind the consensus sequence

Consensus sequence

In molecular biology and bioinformatics, consensus sequence refers to the most common nucleotide or amino acid at a particular position after multiple sequences are aligned. A consensus sequence is a way of representing the results of a multiple sequence alignment, where related sequences are...

 5'-(G/T)GGGCGG(G/A)(G/A)(C/T)-3' (GC box element). It was discovered in 1983 and has since been modified to form Sp1C, which has a zinc finger protein

Zinc finger

Zinc fingers are small protein structural motifs that can coordinate one or more zinc ions to help stabilize their folds. They can be classified into several different structural families and typically function as interaction modules that bind DNA, RNA, proteins, or small molecules...

 DNA-binding domain.

In the SV40

SV40

SV40 is an abbreviation for Simian vacuolating virus 40 or Simian virus 40, a polyomavirus that is found in both monkeys and humans...

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

Sp1 has been used as a control protein to compare with when studying the increase or decrease of the aryl hydrocarbon receptor

Aryl hydrocarbon receptor

The Aryl hydrocarbon receptor is a member of the family of basic-helix-loop-helix transcription factors. AhR is a cytosolic transcription factor that is normally inactive, bound to several co-chaperones...

 and/or the estrogen receptor

Estrogen receptor

Estrogen receptor refers to a group of receptors that are activated by the hormone 17β-estradiol . Two types of estrogen receptor exist: ER, which is a member of the nuclear hormone family of intracellular receptors, and the estrogen G protein-coupled receptor GPR30 , which is a G protein-coupled...

, since it binds to both and generally remains at a relatively constant level.

Interactions

Sp1 transcription factor has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with MEF2C

MEF2C

Myocyte-specific enhancer factor 2C also known as MADS box transcription enhancer factor 2, polypeptide C is a protein that in humans is encoded by the MEF2C gene. MEF2C is a transcription factor in the Mef2 family.-Genomics:...

, MEF2D

MEF2D

Myocyte-specific enhancer factor 2D is a protein that in humans is encoded by the MEF2D gene.-Interactions:MEF2D has been shown to interact with YWHAQ, MAPK7, EP300, Sp1 transcription factor, Myocyte-specific enhancer factor 2A, NFATC2 and CABIN1....

, E2F1

E2F1

Transcription factor E2F1 is a protein that in humans is encoded by the E2F1 gene.-Interactions:E2F1 has been shown to interact with NCOA6, Retinoblastoma-like protein 1, Retinoblastoma protein, GTF2H1, SKP2, PURA, NPDC1, Sp2 transcription factor, Sp1 transcription factor, CUL1, ARID3A, TOPBP1,...

, POU2F1

POU2F1

POU domain, class 2, transcription factor 1 is a protein that in humans is encoded by the POU2F1 gene.-Interactions:POU2F1 has been shown to interact with SNAPC4, Ku80, Glucocorticoid receptor, Sp1 transcription factor, NPAT, POU2AF1, Host cell factor C1, TATA binding protein, RELA, Nuclear...

, Host cell factor C1

Host cell factor C1

Host cell factor is a protein that in humans is encoded by the HCFC1 gene.-Interactions:Host cell factor C1 has been shown to interact with HDAC1, Histone deacetylase 2, OGT, SIN3A, SUDS3, ZBTB17, Sp1 transcription factor, MLL, PPP1CA, POU2F1, PDCD2, WDR5, CREB3 and GABPA.-Further reading:...

, RELA

RELA

Transcription factor p65 is a protein that in humans is encoded by the RELA gene.-Interactions:RELA has been shown to interact with NFKBIB, ETHE1, NFKBIE, RFC1, TRIB3, CREB binding protein, Neutrophil cytosolic factor 1, Glucocorticoid receptor, MTPN, BRCA1, C-Fos, POU2F1, BTRC, TATA-binding...

, CEBPB

CEBPB

CCAAT/enhancer-binding protein beta is a protein that in humans is encoded by the CEBPB gene.- Function :The protein encoded by this intronless gene is a bZIP transcription factor that can bind as a homodimer to certain DNA regulatory regions. It can also form heterodimers with the related proteins...

, HMGA1

HMGA1

High-mobility group protein HMG-I/HMG-Y is a protein that in humans is encoded by the HMGA1 gene.Mice lacking their variant of HMGA1, i.e., Hmga1-/- mice, are diabetic and express low levels of the insulin receptor.-Interactions:...

, MSX1

MSX1

Msh homeobox 1, also known as MSX1, is a protein that in humans is encoded by the MSX1 gene. MSX1 transcripts are not only found in thyrotrope-derived TSH cells, but also in the TtT97 thyrotropic tumor, which is a well differentiated hyperplastic tissue that produces both TSHß- and a-subunits and...

, GABPA

GABPA

GA-binding protein alpha chain is a protein that in humans is encoded by the GABPA gene.-Interactions:GABPA has been shown to interact with Host cell factor C1, Sp1 transcription factor and Sp3 transcription factor.-External links:...

, Small ubiquitin-related modifier 1

Small ubiquitin-related modifier 1

Small ubiquitin-related modifier 1 is a protein that in humans is encoded by the SUMO1 gene.Most cleft genes have a sumoylation component .-Interactions:...

, Mothers against decapentaplegic homolog 3

Mothers against decapentaplegic homolog 3

Mothers against decapentaplegic homolog 3 also known as SMAD family member 3 or SMAD3 is a protein that in humans is encoded by the SMAD3 gene. SMAD3 is a member of the SMAD family of proteins.The human SMAD3 gene is located on chromosome 15...

, HDAC1

HDAC1

Histone deacetylase 1 is an enzyme that in humans is encoded by the HDAC1 gene.-Interactions:HDAC1 has been shown to interact with RAD9A, DNMT3L, MTA1, FKBP3, CDC20, CDH1, Host cell factor C1, BUB3, Nuclear receptor co-repressor 2, IKZF1, Prohibitin, EVI1, DDX5, DNMT3A, Mothers against...

, Histone deacetylase 2

Histone deacetylase 2

Histone deacetylase 2 is an enzyme that in humans is encoded by the HDAC2 gene.-Interactions:Histone deacetylase 2 has been shown to interact with CHD3, MTA1, FKBP3, CHD4, RCOR1, Retinoblastoma protein, CDC20, RBBP4, CDH1, EED, GTF2I, Host cell factor C1, PHF21A, BUB3, MXD1, HDAC10, RELA, Sp3...

, Huntingtin

Huntingtin

The Huntingtin gene, also called HTT or HD gene, is the IT15 gene which codes for a protein called the huntingtin protein...

, KLF6

KLF6

Krueppel-like factor 6 is a protein that in humans is encoded by the KLF6 gene.It is a tumor suppressor gene.-Interactions:KLF6 has been shown to interact with Sp1 transcription factor.-External links:...

, PSMC5

PSMC5

26S protease regulatory subunit 8 is an enzyme that in humans is encoded by the PSMC5 gene.-Interactions:PSMC5 has been shown to interact with XPB, Sp1 transcription factor, PSMC3 and PSMC4.-Further reading:...

, Apoptosis-antagonizing transcription factor, PPP1R13L

PPP1R13L

RelA-associated inhibitor is a protein that in humans is encoded by the PPP1R13L gene.-Interactions:PPP1R13L has been shown to interact with Sp1 transcription factor and RELA.-Further reading:...

, Steroidogenic factor 1

Steroidogenic factor 1

The steroidogenic factor 1 protein controls sexual development in the embryo and at puberty.SF1 is a member of the nuclear receptor family of intracellular transcription factors and is encoded by the NR5A1 gene .- Function :SF-1 is a critical regulator of reproduction, regulating the transcription...

, Myogenin

Myogenin

Myogenin , also known as MYOG, is a gene.Myogenin is a muscle-specific basic-helix-loop-helix transcription factor involved in the coordination of skeletal muscle development and repair...

, TAL1

TAL1

T-cell acute lymphocytic leukemia protein 1 is a protein that in humans is encoded by the TAL1 gene.The protein encoded by TAL1 is a basic-helix-loop-helix transcription factor.-Interactions:...

, Promyelocytic leukemia protein

Promyelocytic leukemia protein

Probable transcription factor PML is a tumor suppressor protein that in humans is encoded by the PML gene.-Interactions:Promyelocytic leukemia protein has been shown to interact with Retinoic acid receptor alpha, HDAC1, Nerve Growth factor IB, SKI protein, Zinc finger and BTB domain-containing...

 and Ubiquitin C

Ubiquitin C

Ubiquitin is a protein that in humans is encoded by the UBC gene.-Interactions:Ubiquitin C has been shown to interact with SCNN1A, SCNN1G, Parkin , P70-S6 Kinase 1, TRAF6, HDAC3, SFPQ, S100A10, Mothers against decapentaplegic homolog 3, NOTCH1, HIF1A, Epidermal growth factor receptor, E2F1,...

.

Further reading

External links