PELP-1 is a transcription

Transcription (genetics)

Transcription is the process of creating a complementary RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes...

al corepressor for nuclear receptor

Intracellular receptor

Intracellular receptors are receptors located inside the cell rather than on its cell membrane. Examples are the class of nuclear receptors located in the cell nucleus and the IP3 receptor located on the endoplasmic reticulum...

s such as glucocorticoid receptor

Glucocorticoid receptor

The glucocorticoid receptor also known as NR3C1 is the receptor to which cortisol and other glucocorticoids bind....

s and a coactivator for 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...

s.

Activation of protein kinases

PELP-1 has been shown to bind to both estrogen receptor alpha and estrogen receptor beta. It was also reported that protein tyrosine kinases

Tyrosine kinase

A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to a protein in a cell. It functions as an "on" or "off" switch in many cellular functions....

 of the src

Src (gene)

Proto-oncogene tyrosine-protein kinase Src is an enzyme that in humans is encoded by the SRC gene.Src is a proto-oncogene encoding a tyrosine kinase originally discovered by J. Michael Bishop and Harold E. Varmus, for which they won the 1989 Nobel Prize in Physiology or Medicine. It belongs to a...

 family can form a complex with estrogen receptors and PELP-1 and it was reported that when bound to PELP-1 and estrogen receptor alpha the kinase activity of SRC was activated in an estrogen-sensitive manner. Mitogen-activated protein kinase

Mitogen-activated protein kinase

Mitogen-activated protein kinases are serine/threonine-specific protein kinases that respond to extracellular stimuli and regulate various cellular activities, such as gene expression, mitosis, differentiation, proliferation, and cell survival/apoptosis.-Activation:MAP kinases are activated...

s ERK1 and ERK2 were found to become phosphorylated in estrogen-treated cells containing PELP-1 . It was reported that the enhancement of estrogen-induced gene transcription due to PELP-1 could be blocked by protein kinase inhibitors. This suggested a model of PELP-1 function in which estrogen and PELP-1 cooperate to activate protein kinases which in turn activate gene transcription.

Histone deacetylase

When functioning as a corepressor of transcription PELP-1 recruits histone deacetylase

Histone deacetylase

Histone deacetylases are a class of enzymes that remove acetyl groups from an ε-N-acetyl lysine amino acid on a histone. This is important because DNA is wrapped around histones, and DNA expression is regulated by acetylation and de-acetylation. Its action is opposite to that of histone...

. Estrogen has been associated with stimulation of cell proliferation and progression of cells through G₁ to the S phase of the cell cycle

Cell cycle

The cell cycle, or cell-division cycle, is the series of events that takes place in a cell leading to its division and duplication . In cells without a nucleus , the cell cycle occurs via a process termed binary fission...

. The retinoblastoma protein

Retinoblastoma protein

The retinoblastoma protein is a tumor suppressor protein that is dysfunctional in the majority types of cancer. One highly studied function of pRb is to prevent excessive cell growth by inhibiting cell cycle progression until a cell is ready to divide...

(Rb) is a regulator of G₁. It was reported that PELP-1 interacts with Rb. It is not known if estrogen receptors can displace histone deacetylase from Rb.