| 1988 |
GHF-1 (POU1F1) is a homeobox-containing protein; the homeodomain region near its C-terminus functions as its DNA-binding domain, demonstrated by DNase I footprinting with bacterially expressed GHF-1 fusion protein. |
cDNA cloning, sequence analysis, DNase I footprinting with bacterially expressed fusion protein |
Cell |
High |
2902927
|
| 1989 |
The GHF-1/POU1F1 homeodomain is sufficient for sequence-specific DNA binding; the POU-specific domain stimulates DNA binding but does not contact DNA directly; transcriptional activation is mediated by a separate hydroxylated amino-acid-rich domain. |
Domain deletion/truncation analysis, in vitro transcription, DNA-binding assays |
Nature |
High |
2574416
|
| 1989 |
Purified GHF-1/POU1F1 (33 kDa) binds to and activates the GH promoter but does not recognize the prolactin (Prl) promoter; a distinct factor in the same extracts binds the Prl promoter. |
Protein purification, gel-shift assay, in vitro transcription, immunoblotting |
Science |
High |
2563596
|
| 1988 |
Extinction of GH expression in fibroblast × pituitary cell hybrids occurs via repression of GHF-1/POU1F1 protein and mRNA, not via a direct repressor of the GH promoter. |
Somatic cell hybridization, in vivo transfection, in vitro transcription, DNase I footprinting, immunoblotting |
Cell |
High |
3167985
|
| 1990 |
POU1F1/Pit-1 binds to and activates cell-specific elements in both the GH and PRL gene promoters; 31 and 33 kDa nuclear proteins recognized by a Pit-1/GHF-1 antibody bind these elements in pituitary cells; cotransfection of RSV-Pit-1/GHF-1 into non-pituitary HeLa cells reconstitutes activation of both promoters. |
Protein-DNA binding assays, cotransfection/reporter assay, immunoblotting with Pit-1 antibody |
Molecular endocrinology |
High |
2284007
|
| 1990 |
Sp1 binding to its site on the human GH promoter is mutually exclusive with GHF-1 binding to its distal site (demonstrated by DNase I footprinting), and Sp1 can partially compensate for low GHF-1 concentrations in stimulating transcription. |
DNase I footprinting, cell-free transcription assay |
Molecular and cellular biology |
Medium |
2181288
|
| 1991 |
POU1F1/Pit-1 (or a closely related protein) mediates TRH responsiveness of the human TSHβ (TSHB) gene via a binding site at -128 to -92 bp; demonstrated by DNase I footprinting with thyrotropic tumor extract and transfection studies with an N-terminal deletion of Pit-1/GHF-1. |
DNase I footprinting, deletion analysis, transient transfection with reporter gene |
Proceedings of the National Academy of Sciences of the United States of America |
Medium |
1901656
|
| 1993 |
GHF-1/POU1F1 is required for generation of somatotropes and lactotropes and for GH and PRL gene expression during pituitary development; immortalization of GHF-1-expressing progenitors that lack GH/PRL results in dwarfism, and an early-acting GHF-1 transcriptional enhancer was identified in this progenitor context. |
Transgenic mouse model (GHF-1 promoter driving SV40 T-antigen), cell line derivation, functional enhancer assay |
Genes & development |
High |
8096199
|
| 1993 |
POU1F1/Pit-1 binds to three A-T-rich regions (TSH A, B, C) in the 5'-flanking region of the rat TSHβ gene; TSH A and TSH C each confer TRH-stimulated and/or enhanced basal activity to a heterologous promoter, and all three elements bind in vitro-translated Pit-1 with defined affinities. |
Gel mobility shift assay with antibody supershift, transient transfection reporter assay, in vitro translated protein binding |
Biochemistry |
Medium |
8364038
|
| 1995 |
GHF-1/POU1F1 undergoes M-phase-specific phosphorylation at Thr-220 (within the N-terminal arm of the homeodomain) by a novel mitotic kinase activity distinct from Cdc2 or PKA, transiently inhibiting its DNA-binding activity during mitosis; PKA does not phosphorylate this inhibitory site in living cells. |
In vivo phosphorylation analysis, in vitro kinase assays, site-directed mutagenesis, cell synchronization, DNA-binding assays |
Molecular and cellular biology |
High |
8524234
|
| 1995 |
GHF-1/POU1F1 and PKA synergistically activate the rat PRL promoter via the FP I site; GHF-1 is necessary but not sufficient for the full PKA response, which also requires a GHF-1-independent ubiquitous factor acting at FP I. |
Cotransfection reconstitution assay in HeLa cells with expression vectors, site-specific mutagenesis, luciferase reporter |
Molecular endocrinology |
Medium |
7659093
|
| 1995 |
GHRH increases GHF-1/POU1F1 mRNA levels via a transcriptional mechanism not requiring new protein synthesis; IGF-1 inhibits basal GHF-1 mRNA and blocks GHRH induction; somatostatin has no effect. |
Primary anterior pituitary cell culture, Northern blotting, actinomycin D and cycloheximide treatments, pharmacological activation of second messengers |
Endocrinology |
Medium |
7649093
|
| 1995 |
Retinoic acid induces GHF-1/POU1F1 mRNA and protein expression in pituitary cell lines via sequences between -400 and -90 bp of the GHF-1/Pit-1 promoter containing two CREs, both of which are required; T3 decreases GHF-1 mRNA and promoter activity in GH4C1 cells and blocks RA stimulation. |
Northern blotting, Western blotting, gel retardation assay, promoter-reporter transfection with deletion constructs |
Endocrinology |
Medium |
7588287
|
| 1995 |
T3 represses GHF-1/POU1F1 gene expression by transcriptional interference with CRE-containing promoter elements (bp -90 to -200), not through a canonical TRE, and also interferes with GHF-1 binding to a positive autoregulatory element at bp -45 to -63. |
Promoter-reporter transfection with deletion constructs, in vitro DNA-binding assay, RT-PCR/Northern |
Molecular and cellular biology |
Medium |
7565785
|
| 1996 |
POU1F1/GHF-1 functions as a cell-specific integrator of Ras signaling by forming a composite binding site with Ets-1 at positions -217 to -190 of the rat PRL promoter; both Ets-1 and GHF-1 binding sites are required for Ras/Raf activation; the composite element confers Ras responsiveness when inserted into the GH promoter. |
Site-directed mutagenesis of promoter, luciferase reporter assay, EMSA, insertion of composite element into heterologous promoter |
The Journal of biological chemistry |
High |
8798730
|
| 1998 |
GHF-1/POU1F1 physically interacts with RXR (strong), RAR (weak), and TR (weak) via in vitro GST pull-down; GHF-1 and TR/RXR or RAR/RXR heterodimers form a ternary complex with the GH promoter fragment, and GHF-1 increases receptor binding to the promoter under limiting conditions. |
GST pull-down (in vitro binding), EMSA (ternary complex), reporter assay |
FASEB journal |
Medium |
9737723
|
| 1998 |
In pituitary cells, GHF-1/POU1F1 converts T3/RA receptor-mediated repression into ligand-dependent activation of the GH promoter; a truncated T3 receptor lacking N-terminus and DNA-binding domain still activates the GH promoter in the presence of GHF-1 and RXR, indicating protein-protein interaction is sufficient. |
Transient transfection reporter assay in HeLa cells with/without GHF-1, GH promoter activity measurement |
The Journal of biological chemistry |
Medium |
9765286
|
| 1999 |
VDR and GHF-1/Pit-1 synergistically activate the PRL promoter; coactivators CBP and SRC-1 enhance VDR-mediated activation via the AF-2 domain; CBP also enhances GHF-1-mediated activation of the PRL promoter. |
Transient transfection reporter assay in HeLa cells, cotransfection with VDR, GHF-1, SRC-1, and CBP expression vectors, AF-2 mutant analysis |
Molecular endocrinology |
Medium |
10406465
|
| 1999 |
POU1F1/Pit-1 directly binds the serum response element (SRE) in the c-fos promoter (albeit with lower affinity than its cognate site) and activates c-fos transcription in a phosphorylation-dependent manner; Pit-1 phosphorylation sites are required for c-fos promoter activity but not for hormonal gene regulation. |
Gel shift analysis, overexpression in PC12 cells, antisense-mediated knockdown in GH3 cells, reporter assay with mutant Pit-1 phosphorylation sites |
Molecular endocrinology |
Medium |
10319324
|
| 1999 |
POU1F1/Pit-1 binds A/T-rich sequences within a 203-bp enhancer element of the human GH locus control region (LCR) HSII region and is required for enhancer activity in pituitary cells in culture and in transgenic mice. |
EMSA (competition and antibody supershift with recombinant protein), deletion analysis, promoter-reporter transfection, transgenic mouse reporter |
Molecular endocrinology |
High |
10446901
|
| 2005 |
POU1F1 mutation E230K reduces transactivation but not DNA-binding affinity; R172Q reduces both DNA binding and transactivation; ins778A abolishes DNA binding and reduces transactivation — demonstrating mutation-specific functional defects in the context of CPHD. |
Functional studies: transactivation reporter assay, DNA-binding affinity assay (EMSA or similar) |
The Journal of clinical endocrinology and metabolism |
Medium |
15928241
|
| 2005 |
LHX4 binds to a human-specific element in the POU1F1 upstream regulatory sequence and activates POU1F1 transcription; mutant LHX4 proteins from CPHD patients fail to bind and activate the POU1F1 regulatory sequence but do not act as dominant negatives over normal LHX4. |
Recombinant protein expression in CHO cells, DNA-binding assay, reporter/transactivation assay |
The Journal of clinical endocrinology and metabolism |
Medium |
15998782
|
| 2008 |
OTX2 binds to target sequences within the POU1F1 promoter and markedly transactivates it (~19-fold); a frameshift OTX2 mutation retaining the homeodomain but losing the transactivation domain barely retains this activity with no dominant-negative effect. |
Transfection reporter (luciferase) assay, nuclear localization assay, OTX2 wild-type vs. mutant comparison |
The Journal of clinical endocrinology and metabolism |
Medium |
18628516
|
| 2008 |
POU1F1 mutation S179R (in the POU-specific domain) abolishes interaction with coactivator CBP on the PRL promoter (but not with LHX3) and markedly reduces DNA binding and transactivation, with normal nuclear accumulation. |
Transactivation reporter assay, EMSA (DNA binding), nuclear accumulation assay, functional interaction studies in alphaT3 cells |
The Journal of clinical endocrinology and metabolism |
Medium |
16968807
|
| 2008 |
POU1F1 proliferative response to GHRH is cell-type specific and requires Pit-1/GHF-1 expression; Pit-1 is needed for downstream GHRH receptor signaling effects on cell proliferation (p27 degradation), demonstrated by Pit-1 siRNA knockdown in GH3-GHRHR cells and by exogenous Pit-1 expression in CHO-4 cells. |
siRNA knockdown, overexpression, cell proliferation assays, Western blotting for cell cycle regulators |
Journal of cellular physiology |
Medium |
17941086
|
| 2009 |
POU1F1 binds directly to a site near the Syt1 (synaptotagmin I) initiation exon in GH3 pituitary cells (ChIP, in vitro binding), and POU1F1 knockdown reduces endogenous Syt1 mRNA; luciferase reporter assays confirm a POU1F1-regulated internal Syt1 promoter. |
Chromatin immunoprecipitation (ChIP), shRNA knockdown, in vitro DNA binding, luciferase reporter transfection |
Molecular endocrinology |
Medium |
19608642
|
| 2012 |
IGF-1 inhibits GH gene expression by disrupting the POU1F1/CBP complex at the GH promoter; IGF-1 receptor signaling prevents CBP binding to the GH promoter (shown by ChIP), and a CBP S436A phosphorylation-dead mutant abolishes IGF-1 inhibition, elevating serum GH in knock-in mice. |
ChIP assay, luciferase reporter, CBP mutant (S436A) knock-in mouse model, serum GH/GHRH stimulation assay |
Molecular and cellular biology |
High |
22890843
|
| 2012 |
POU1F1 directly binds multiple sites at the HSII region of the hGH LCR, confers robust POU1F1-dependent activation of hGH-N in a minichromosome model, and is required for POU1F1-dependent histone acetylation and methylation throughout the LCR/hGH-N domain; one binding site maps to the 3' UTR of a primate-specific LINE-1 retrotransposon. |
Minichromosome reporter system, in vitro DNA binding, ChIP for histone modifications, transfection assays |
Journal of molecular biology |
Medium |
22094313
|
| 2015 |
POU1F1 Pro76Leu mutation (in the transactivation domain) selectively alters DNA-binding affinity at hGH-LCR and hGH1 sites (but not PRL sites), enhances interactions with cofactors PITX1, LHX3a, and ELK1 (by Co-IP), and causes dramatic loss of protein expression in homozygous knock-in mice despite normal mRNA levels. |
Bandshift (EMSA) assay, Co-immunoprecipitation, knock-in mouse model, immunoblotting |
Human molecular genetics |
High |
26612202
|
| 2015 |
ERK (downstream of FGFR2) directly interacts with and phosphorylates POU1F1, increasing POU1F1 binding to the Mre11 promoter and repressing Mre11 expression, thereby decreasing double-strand break repair in breast cancer cells. |
Co-immunoprecipitation, phosphorylation assay, ChIP on Mre11 promoter, reporter assay, shRNA knockdown |
Human molecular genetics |
Medium |
25788520
|
| 2019 |
POU1F1 (Pit-1) in breast tumor cells drives recruitment and M2 polarization of macrophages via transcriptional regulation of CXCL12 secretion; TAMs in turn promote tumor growth, angiogenesis, and lung metastasis. |
In vitro co-culture, zebrafish and mouse xenograft models, CXCL12 measurement, flow cytometry for macrophage markers, shRNA knockdown of POU1F1 |
The Journal of pathology |
Medium |
31292963
|
| 2020 |
POU1F1 mediates ADTRP-induced transcription of TFPI by binding to a 50-bp ADTRP-response element (-806 to -756 bp upstream of TFPI TSS); knockdown of POU1F1 abolishes ADTRP-mediated TFPI transcription; direct binding confirmed by ChIP and EMSA. |
Luciferase reporter assay (large/small deletions), ChIP, EMSA, siRNA knockdown |
Gene |
Medium |
32445923
|
| 2021 |
POU1F1 transcriptionally regulates the LDHA gene in breast cancer cells; POU1F1 overexpression increases LDHA expression and lactate production, promoting glycolytic reprogramming; LDHA knockdown in POU1F1-overexpressing cells reduces tumor volume and [18F]FDG uptake in xenograft mice. |
shRNA knockdown, overexpression, luciferase reporter, xenograft mouse model with PET imaging, human primary cancer cell cultures |
Oncogene |
Medium |
33714987
|
| 2021 |
HMGA1B/2 transcriptionally activates POU1F1 in gastric cancer; POU1F1 in turn promotes CXCL12/CXCR4-dependent macrophage polarization; GST pull-down and Co-IP confirmed physical interaction between HMGA1B/2 and POU1F1; ChIP and dual luciferase assays confirmed HMGA1B/2 transcriptional regulation of POU1F1. |
GST pull-down, Co-immunoprecipitation, ChIP, dual luciferase reporter assay, xenograft mouse model |
Cell death & disease |
Medium |
33927188
|
| 2021 |
The stem cell RNA-binding protein Musashi1 directly binds the Pou1f1 mRNA 3' UTR and exerts translational repression of POU1F1 in female somatotropes; leptin signaling is required to relieve this repression; Musashi immunoprecipitation from whole pituitary co-purifies Pou1f1 mRNA. |
RNA immunoprecipitation, translational reporter assay, Cre-LoxP Lepr-null somatotrope purification, immunocytochemistry, single-cell RNA-seq |
Endocrinology |
Medium |
33373440
|
| 2021 |
Heterozygous missense POU1F1 variants that affect only the POU1F1 beta isoform retain repressor activity and shift splicing to favor the beta isoform, causing dominant-negative loss of function; identified by high-throughput splicing reporter assay testing 1,070 SNVs. |
High-throughput splicing reporter assay (1,070 variants), functional repressor activity assay, clinical co-segregation in multiple families |
American journal of human genetics |
High |
34270938
|
| 2021 |
A POU1F1 intronic variant (c.143-69T>G in intron 1 of PIT-1α) shifts splicing to produce exclusively the PIT-1β transcript; the PIT-1β-Ile51Ser mutant protein represses PIT-1α transcriptional activity and abolishes transactivation of the rat PRL promoter in GH3 cells, causing CPHD. |
Gene splicing experiments, luciferase reporter assay, lymphocyte mRNA expression analysis |
European journal of endocrinology |
Medium |
33886498
|
| 2022 |
The intronic Pou1f1 variant c.143-83A>G disrupts a branch site in the pre-mRNA, shifting splicing to decrease the alpha isoform, increase the beta isoform, and produce an exon-skipped transcript; homozygous knock-in mice show pituitary hypoplasia, somatotroph reduction, dwarfism, and IGF-1/T4 deficiency. |
Knock-in mouse model (CRISPR/genome engineering), RNA-seq, RT-PCR, immunohistochemistry, splicing analysis in cultured cells |
Endocrinology |
High |
36427334
|
| 2016 |
Leptin signaling to somatotropes is required to maintain POU1F1 protein levels and all POU1F1-dependent hormones (GH, PRL, TSH); reduction is sex-dependent (occurs in females but not males for TSH and PRL), demonstrating a tropic role for leptin in controlling POU1F1-dependent cell lineages. |
Cre-LoxP conditional Lepr knockout in somatotropes, FACS-purified cell populations, enzyme immunoassays, qPCR |
Endocrinology |
Medium |
27571135
|
| 2001 |
POU1F1 W193R missense mutation (in the fourth alpha-helix of the POU-specific domain) causes a ~500-fold reduction in DNA binding and transcriptional activation; a frameshift (747delA) removes the entire DNA recognition helix of the homeodomain, producing a nonfunctional protein. |
DNA-binding assay, transactivation reporter assay, cell transfection |
The Journal of clinical endocrinology and metabolism |
Medium |
11297581
|
| 2023 |
Genetic epistasis between Pou1f1 and Six3 in mice: Six3 heterozygotes have pituitary dysmorphology; Six3+/-; Pou1f1+/dw double heterozygotes have a pronounced pituitary phenotype including pituitary growth through the palate, supporting digenic pituitary disease. |
Genetically engineered double-heterozygous mice, pituitary histology, phenotypic analysis |
Human molecular genetics |
Medium |
35951005
|