PELP1

This gene encodes a transcription factor which coactivates transcription of estrogen receptor responsive genes and corepresses genes activated by other hormone receptors or sequence-specific transcription factors. Expression of this gene is regulated by both members of the estrogen receptor family. This gene may be involved in the progression of several types of cancer. Alternative splicing results in multiple transcript variants. [provided by RefSeq, May 2013]

Full Name

Proline, Glutamate And Leucine Rich Protein 1

Function

Coactivator of estrogen receptor-mediated transcription and a corepressor of other nuclear hormone receptors and sequence-specific transcription factors (PubMed:14963108).
Plays a role in estrogen receptor (ER) genomic activity when present in the nuclear compartment by activating the ER target genes in a hormonal stimulation dependent manner. Can facilitate ER non-genomic signaling via SRC and PI3K interaction in the cytosol. Plays a role in E2-mediated cell cycle progression by interacting with RB1. May have important functional implications in ER/growth factor cross-talk. Interacts with several growth factor signaling components including EGFR and HRS. Functions as the key stabilizing component of the Five Friends of Methylated CHTOP (5FMC) complex; the 5FMC complex is recruited to ZNF148 by methylated CHTOP, leading to desumoylation of ZNF148 and subsequent transactivation of ZNF148 target genes. Component of the PELP1 complex involved in the nucleolar steps of 28S rRNA maturation and the subsequent nucleoplasmic transit of the pre-60S ribosomal subunit. Regulates pre-60S association of the critical remodeling factor MDN1 (PubMed:21326211).
May promote tumorigenesis via its interaction with and modulation of several oncogenes including SRC, PI3K, STAT3 and EGFR. Plays a role in cancer cell metastasis via its ability to modulate E2-mediated cytoskeleton changes and cell migration via its interaction with SRC and PI3K.

Biological Process

Cellular response to estrogen stimulusManual Assertion Based On ExperimentIDA:UniProtKB
Positive regulation of transcription by RNA polymerase IIManual Assertion Based On ExperimentIDA:UniProtKB

Cellular Location

Nucleus, nucleolus
Nucleus, nucleoplasm
Nucleus
Cytoplasm
Mainly found in the nucleoplasm, with low levels detected in the cytoplasm (By similarity).
Also found associated with the plasma membrane. Mainly in cytoplasm in a subset of breast tumors. Localization is widely deregulated in endometrial cancers with predominantly cytoplasm localization in high-grade endometrial tumors (PubMed:16140940).

PTM

Transiently sumoylated, preferentially conjugated to SUMO2 or SUMO3. Sumoylation causes nucleolar exclusion of PELP1 and promotes the recruitment of MDN1 to pre-60S particles. Desumoylation by SUMO isopeptidase SENP3 is needed to release both PELP1 and MDN1 from pre-ribosomes.