A regulatory sequence is a segment of a nucleic acid molecule which is capable of increasing or decreasing the expression of specific genes within an organism. Regulation of gene expression is an essential feature of all living organisms and viruses.
Histone methyltransferases (HMT) are histone-modifying enzymes, that catalyze the transfer of one, two, or three methyl groups to lysine and arginine residues of histone proteins. The attachment of methyl groups occurs predominantly at specific lysine or arginine residues on histones H3 and H4. Two major types of histone methyltranferases exist, lysine-specific and arginine-specific. In both types of histone methyltransferases, S-Adenosyl methionine (SAM) serves as a cofactor and methyl donor group.
The genomic DNA of eukaryotes associates with histones to form chromatin. The level of chromatin compaction depends heavily on histone methylation and other post-translational modifications of histones. Histone methylation is a principal epigenetic modification of chromatin that determines gene expression, genomic stability, stem cell maturation, cell lineage development, genetic imprinting, DNA methylation, and cell mitosis.
In molecular biology and genetics, transcriptional regulation is the means by which a cell regulates the conversion of DNA to RNA (transcription), thereby orchestrating gene activity. A single gene can be regulated in a range of ways, from altering the number of copies of RNA that are transcribed, to the temporal control of when the gene is transcribed. This control allows the cell or organism to respond to a variety of intra- and extracellular signals and thus mount a response. Some examples of this include producing the mRNA that encode enzymes to adapt to a change in a food source, producing the gene products involved in cell cycle specific activities, and producing the gene products responsible for cellular differentiation in multicellular eukaryotes, as studied in evolutionary developmental biology.
Regulation of gene expression, or gene regulation, includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products. Sophisticated programs of gene expression are widely observed in biology, for example to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. Virtually any step of gene expression can be modulated, from transcriptional initiation, to RNA processing, and to the post-translational modification of a protein. Often, one gene regulator controls another, and so on, in a gene regulatory network.
Zinc finger protein GLI1 also known as glioma-associated oncogene is a protein that in humans is encoded by the GLI1 gene. It was originally isolated from human glioblastoma cells.
Methyl-CpG-binding domain protein 1 is a protein that in humans is encoded by the MBD1 gene. The protein encoded by MBD1 binds to methylated sequences in DNA, and thereby influences transcription. It binds to a variety of methylated sequences, and appears to mediate repression of gene expression. It has been shown to play a role in chromatin modification through interaction with the histone H3K9 methyltransferase SETDB1. H3K9me3 is a repressive modification.
Transcriptional repressor CTCF also known as 11-zinc finger protein or CCCTC-binding factor is a transcription factor that in humans is encoded by the CTCF gene. CTCF is involved in many cellular processes, including transcriptional regulation, insulator activity, V(D)J recombination and regulation of chromatin architecture.
Zinc finger and BTB domain-containing protein 16 is a protein that in humans is encoded by the ZBTB16 gene.
Methyl-CpG-binding domain protein 2 is a protein that in humans is encoded by the MBD2 gene.
p120 catenin, or simply p120, also called catenin delta-1, is a protein that in humans is encoded by the CTNND1 gene.
Transcription regulator protein BACH1 is a protein that in humans is encoded by the BACH1 gene.
Hypermethylated in cancer 1 protein is a protein that in humans is encoded by the HIC1 gene.
Nucleus accumbens-associated protein 1 is a protein that in humans is encoded by the NACC1 gene.
Zinc finger and BTB domain-containing protein 7A is a protein that in humans is encoded by the ZBTB7A gene.
Krueppel-like factor 12 is a protein that in humans is encoded by the KLF12 gene.
POZ-, AT hook-, and zinc finger-containing protein 1 is a protein that in humans is encoded by the PATZ1 gene.
Zinc finger and BTB domain-containing protein 32 is a protein that in humans is encoded by the 1960 bp ZBTB32 gene. The 52 kDa protein is a transcriptional repressor and the gene is expressed in T and B cells upon activation, but also significantly in testis cells. It is a member of the Poxviruses and Zinc-finger (POZ) and Krüppel (POK) family of proteins, and was identified in multiple screens involving either immune cell tumorigenesis or immune cell development.
Zinc finger protein 161 homolog is a protein that in humans is encoded by the ZBTB14 gene.
Epigenomics is the study of the complete set of epigenetic modifications on the genetic material of a cell, known as the epigenome. The field is analogous to genomics and proteomics, which are the study of the genome and proteome of a cell. Epigenetic modifications are reversible modifications on a cell's DNA or histones that affect gene expression without altering the DNA sequence. Epigenomic maintenance is a continuous process and plays an important role in stability of eukaryotic genomes by taking part in crucial biological mechanisms like DNA repair. Plant flavones are said to be inhibiting epigenomic marks that cause cancers. Two of the most characterized epigenetic modifications are DNA methylation and histone modification. Epigenetic modifications play an important role in gene expression and regulation, and are involved in numerous cellular processes such as in differentiation/development and tumorigenesis. The study of epigenetics on a global level has been made possible only recently through the adaptation of genomic high-throughput assays.
Juliet M Daniel is a Barbadian-born Canadian biology professor at McMaster University, where her research focuses on cancer biology. Daniel is recognized in the cancer biology field for the discovery and naming of the gene Kaiso, and is the recipient of several prestigious awards in recognition of her research and leadership, including an Ontario Premier Research Excellence Award and a Vice-Chancellor Award from the University of the West Indies.
