Scaffold attachment factor B, also known as SAFB, is a gene with homologs that have been studied in humans and mice. [5]
This gene encodes a DNA-binding protein that has specificity for scaffold or matrix attachment region DNA elements (S/MAR DNA). This protein is thought to be involved in attaching the base of chromatin loops to the nuclear matrix but there are conflicting views as to whether this protein is a component of chromatin, the nuclear matrix, or both. Scaffold attachment factors are a subset of nuclear matrix proteins (NMP) with enriched binding to AT-rich S/MAR sequences. The SAF-B protein is thought to serve as a molecular base to assemble a 'transcriptosome complex' in the vicinity of actively transcribed genes. It is involved in the regulation of the heat shock protein 27 transcription and also can act as an estrogen receptor corepressor. This gene is a candidate gene for breast tumorigenesis. [5]
SAFB has been shown to interact with:
Histone acetyltransferase p300 also known as p300 HAT or E1A-associated protein p300 also known as EP300 or p300 is an enzyme that, in humans, is encoded by the EP300 gene. It functions as histone acetyltransferase that regulates transcription of genes via chromatin remodeling by allowing histone proteins to wrap DNA less tightly. This enzyme plays an essential role in regulating cell growth and division, prompting cells to mature and assume specialized functions (differentiate), and preventing the growth of cancerous tumors. The p300 protein appears to be critical for normal development before and after birth.
In molecular biology and genetics, transcription coregulators are proteins that interact with transcription factors to either activate or repress the transcription of specific genes. Transcription coregulators that activate gene transcription are referred to as coactivators while those that repress are known as corepressors. The mechanism of action of transcription coregulators is to modify chromatin structure and thereby make the associated DNA more or less accessible to transcription. In humans several dozen to several hundred coregulators are known, depending on the level of confidence with which the characterisation of a protein as a coregulator can be made. One class of transcription coregulators modifies chromatin structure through covalent modification of histones. A second ATP dependent class modifies the conformation of chromatin.
Estrogen receptor alpha (ERα), also known as NR3A1, is one of two main types of estrogen receptor, a nuclear receptor that is activated by the sex hormone estrogen. In humans, ERα is encoded by the gene ESR1.
The nuclear receptor coactivator 2 also known as NCoA-2 is a protein that in humans is encoded by the NCOA2 gene. NCoA-2 is also frequently called glucocorticoid receptor-interacting protein 1 (GRIP1), steroid receptor coactivator-2 (SRC-2), or transcriptional mediators/intermediary factor 2 (TIF2).
The nuclear receptor coactivator 3 also known as NCOA3 is a protein that, in humans, is encoded by the NCOA3 gene. NCOA3 is also frequently called 'amplified in breast 1' (AIB1), steroid receptor coactivator-3 (SRC-3), or thyroid hormone receptor activator molecule 1 (TRAM-1).
The nuclear receptor co-repressor 1 also known as thyroid-hormone- and retinoic-acid-receptor-associated co-repressor 1 (TRAC-1) is a protein that in humans is encoded by the NCOR1 gene.
Retinoid X receptor alpha (RXR-alpha), also known as NR2B1 is a nuclear receptor that in humans is encoded by the RXRA gene.
C-jun-amino-terminal kinase-interacting protein 1 is an enzyme that in humans is encoded by the MAPK8IP1 gene.
Heterogeneous nuclear ribonucleoprotein U is a protein that in humans is encoded by the HNRNPU gene.
Nuclear receptor-interacting protein 1 (NRIP1) also known as receptor-interacting protein 140 (RIP140) is a protein that in humans is encoded by the NRIP1 gene.
E3 SUMO-protein ligase PIAS4 is one of several protein inhibitor of activated STAT (PIAS) proteins. It is also known as protein inhibitor of activated STAT protein gamma, and is an enzyme that in humans is encoded by the PIAS4 gene.
C-terminal-binding protein 1 also known as CtBP1 is a protein that in humans is encoded by the CTBP1 gene. CtBP1 is one of two CtBP proteins, the other protein being CtBP2.
Mediator of RNA polymerase II transcription subunit 1 also known as DRIP205 or Trap220 is a subunit of the Mediator complex and is a protein that in humans is encoded by the MED1 gene. MED1 functions as a nuclear receptor coactivator.
E3 SUMO-protein ligase PIAS3 is an enzyme that in humans is encoded by the PIAS3 gene.
Nuclear receptor coactivator 6 is a protein that in humans is encoded by the NCOA6 gene.
Tripartite motif-containing 24 (TRIM24) also known as transcriptional intermediary factor 1α (TIF1α) is a protein that, in humans, is encoded by the TRIM24 gene.
TATA-binding protein-associated factor 2N is a protein that in humans is encoded by the TAF15 gene.
Vinexin is a protein that in humans is encoded by the SORBS3 gene.
Scaffold attachment factor B2 is a protein that in humans is encoded by the SAFB2 gene.
CREB/ATF bZIP transcription factor is a protein that in humans is encoded by the CREBZF gene.