What are estrogen responsive elements?
What are estrogen responsive elements?
estrogen response element. bp. base pair(s). The estrogen receptor (ER)1 is a transcription factor that regulates the expression of estrogen-responsive genes by binding to a specific DNA sequence found in their regulatory regions. This sequence is called the estrogen response element (ERE).
How many estrogen receptors are there?
two different
There are two different forms of the estrogen receptor, usually referred to as α and β, each encoded by a separate gene (ESR1 and ESR2, respectively).
What genes does estrogen activate?
Several genes that are induced by estrogens in MCF-7 cells are activated through one or more GC-rich sites in their regulatory regions and these include the cathepsin D, E2F1, bcl-2, c-fos, adenosine deaminase, insulinlike growth factor binding protein 4, and retinoic acid receptor alpha 1 genes.
How does estrogen decrease gene expression?
How does estrogen regulate gene expression? Estrogen can bind to classic estrogen receptors (ER), ERα and ERβ, which act as ligand-gated transcription factors that bind to DNA with the help of co-activators and co-repressors and alter DNA transcription (see [2] for more details).
What is HRE in biology?
HRE allows interaction of the receptor with the DNA leading to transcriptional activation or repression of target gene.
What is the estrogen signaling pathway?
The estrogen signaling pathway refers to all proteins of estrogen function and related regulatory proteins. Estrogen is a substance that promotes the development of secondary sexual characteristics and sexual organ maturation in female animals. It is secreted by the ovary and placenta of female animals.
Where are the most estrogen receptors?
Estrogen receptors (ERs) are members of the superfamily class of nuclear receptors located in either the cell cytoplasm or nucleus and which function as transcription factors (Lovejoy, 2005).
Is it better to be hormone receptor positive or negative?
Hormone receptor-positive cancers tend to grow more slowly than those that are hormone receptor-negative. Women with hormone receptor-positive cancers tend to have a better outlook in the short-term, but these cancers can sometimes come back many years after treatment.
How is estrogen activated?
Estrogens exert their actions by binding to specific receptors, the estrogen receptors (ERs), which in turn activate transcriptional processes and/or signaling events that result in the control of gene expression.
How is estrogen receptor regulated?
As a nuclear receptor, ER has a DNA-binding domain (DBD) that enables it to directly regulate gene expression events and a ligand-binding domain (LBD) that renders it responsive to an activating ligand, namely oestrogen.
What is Oestrogen gene transcription?
Oestrogen receptor (ER) is a transcription factor that regulates gene expression events that culminate in cell division, an important property that contributes to its critical role in mammary gland development.
How does estrogen affect transcription?
What is hormone responsiveness?
Listen to pronunciation. (HOR-mone reh-SPONT-siv) In oncology, describes cancer that responds to hormone treatment.
What is a responsive element?
Response elements are short sequences of DNA within a gene promoter or enhancer region that are able to bind specific transcription factors and regulate transcription of genes. Under conditions of stress, a transcription activator protein binds to the response element and stimulates transcription.
What activates estrogen receptor?
ESTROGEN RECEPTOR LIGAND INDEPENDENT SIGNALING This ligand-independent estrogen receptor activation is mainly triggered by phosphorylation on specific residues (e.g. serine and tyrosine) in the receptors themselves, or their association with coregulators (described below).
Can estrogen receptors change?
The characteristics of a breast cancer — including hormone receptor status and HER2 status — can change over time. These changes may happen because the cancer cells change themselves or because treatment changes the cells.
What percentage is considered ER positive?
Guidelines for the use of chemotherapy and endocrine therapy recently recommended that estrogen receptor (ER) status be considered positive if ≥1% of tumor cells demonstrate positive nuclear staining by immunohistochemistry. In clinical practice, a range of thresholds are used; a common one is 10% positivity.
What percentage of breast cancers are estrogen receptor-positive?
About 70-80 percent of breast cancers are hormone receptor-positive [18,29]. Hormone receptor status is part of breast cancer staging and helps guide your treatment. You may hear the term “biomarker” to describe hormone receptors.
What is estrogen receptor gene?
How many Hox genes are in Drosophila melanogaster?
eight Hox genes
Drosophila, like all insects, has eight Hox genes. These are clustered into two complexes, both of which are located on chromosome 3.
Does oestrogen increase transcription?
Estrogen stimulation of protein synthesis was first observed in the 1960s, leading to active discussion about whether estrogen directly stimulates transcription or translation (5,6,7). The discovery of ER solidified the idea that estrogen can directly regulate RNA synthesis (8,9).
Does DHEA increase estrogen?
DHEA produced a significant rise in androgens levels, whereas HRT did not. Moreover, DHEA alone induced a significantly lower increase in estrogens and beta-endorphin levels and a higher decrease in cortisol levels than HRT. DHEA and HRT also produced a significant similar increase in allopregnanolone levels.
What is hormone responsive tumors?
If a tumor is hormone-sensitive, it means that there are special proteins called receptors on cells surface. When the hormone bind the matched receptor, it results in growth and spread of cancer cells.
What is a response element genetics?
By definition, a “response element” is a portion of a gene which must be present in order for that gene to respond to some hormone or other stimulus. Response elements are binding sites for transcription factors. Certain transcription factors are activated by stimuli such as hormones or heat shock.