SOX21
Encyclopedia
Transcription factor SOX-21 is a protein
that in humans is encoded by the SOX21 gene
. It is a member of the Sox
gene family of transcription factor
s.
al cellular differentiation
by counteracting the activity of Sox1
, Sox2
, and Sox3
, which maintain neural cells in an undifferentiated state.
SOX21 knockout mice
display hair loss beginning from postnatal day 11. New hair regrowth was initiated a few days later but was followed by renewed hair loss. Sox21 is also expressed in the hair shaft cuticle in humans and consequently variants of the Sox21 gene could be responsible for some hair loss conditions in humans.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the SOX21 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
. It is a member of the Sox
SOX genes
SOX genes encode a family of transcription factors that bind to the minor groove in DNA, and belong to a super-family of genes characterized by a homologous sequence called the HMG box. This HMG box is a DNA binding domain that is highly conserved throughout eukaryotic species...
gene family of 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...
s.
Function
In the chick embryo, Sox21 promotes neuronNeuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
al cellular differentiation
Cellular differentiation
In developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized cell type. Differentiation occurs numerous times during the development of a multicellular organism as the organism changes from a simple zygote to a complex system of...
by counteracting the activity of Sox1
SOX1
SOX1 is a transcription factor in the Sox protein family. SOX1 expression is restricted to neuroectoderm in the tetrapod embryo. SOX1 is involved in early central nervous system development, where it is functionally redundant with SOX3 and to a lesser degree SOX2, and maintenance of neural...
, Sox2
SOX2
SRY -box 2, also known as SOX2, is a transcription factor that is essential to maintain self-renewal of undifferentiated embryonic stem cells....
, and Sox3
SOX3
Transcription factor SOX-3 is a protein that in humans is encoded by the SOX3 gene.This gene encodes a member of the SOX family of transcription factors involved in the regulation of embryonic brain development and in determination of cell fate. The encoded protein acts as a transcriptional...
, which maintain neural cells in an undifferentiated state.
SOX21 knockout mice
Knockout mouse
A knockout mouse is a genetically engineered mouse in which researchers have inactivated, or "knocked out," an existing gene by replacing it or disrupting it with an artificial piece of DNA...
display hair loss beginning from postnatal day 11. New hair regrowth was initiated a few days later but was followed by renewed hair loss. Sox21 is also expressed in the hair shaft cuticle in humans and consequently variants of the Sox21 gene could be responsible for some hair loss conditions in humans.