Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Truncating mutations were found in the PHF8 gene (encoding the PHD finger protein 8) in two unrelated families with X linked mental retardation (XLMR) associated with cleft lip/palate (MIM 300263). Expression studies showed that this gene is ubiquitously transcribed, with strong expression of the mouse orthologue Phf8 in embryonic and adult brain structures. The coded PHF8 protein harbours two functional domains, a PHD finger and a JmjC (Jumonji-like C terminus) domain, implicating it in transcriptional regulation and chromatin remodelling. The association of XLMR and cleft lip/palate in these patients with mutations in PHF8 suggests an important function of PHF8 in midline formation and in the development of cognitive abilities, and links this gene to XLMR associated with cleft lip/palate. Further studies will explore the specific mechanisms whereby PHF8 alterations lead to mental retardation and midline defects.
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PMID:Mutations in PHF8 are associated with X linked mental retardation and cleft lip/cleft palate. 1619 51

We investigated the prevalence of mutations in the PHD finger protein 8 (PHF8) gene in X-linked mental retardation (XLMR) and facial cleft starting from the original cohort of 7712 patients operated on since 1 January 1950 for cleft lip/cleft palate in the Cleft Centre at the Helsinki University Hospital. From this nationwide material, 18 patients including one family with two male patients with cleft lip/cleft palate and unknown cause of mental retardation (MR) were sequenced for the coding regions and splice sites of the PHF8 gene. A novel missense mutation c.836C>T of the PHF8 gene was identified in a Finnish family with multiple-affected male patients. The mutation resides in exon 8 and changes phenylalanine to serine (F279S) in the functionally important Jmonji C domain of the protein. The clinical phenotype of the male patients was characterized by mild MR, mild dysmorphic features, unilateral cleft lip and cleft palate in one and bilateral cleft lip and cleft palate in the other sibling. The mutation was not present in 200 anonymous blood donors (approximately 300 X-chromosomes). To our knowledge, F279S is the third mutation of the PHF8 gene identified so far.
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PMID:Screening of mutations in the PHF8 gene and identification of a novel mutation in a Finnish family with XLMR and cleft lip/cleft palate. 1766 19

Crystallographic analysis of the catalytic domain of PHD finger protein 8 (PHF8), an N(epsilon)-methyl lysine histone demethylase associated with mental retardation and cleft lip/palate, reveals a double-stranded beta-helix fold with conserved Fe(II) and cosubstrate binding sites typical of the 2-oxoglutarate dependent oxygenases. The PHF8 active site is highly conserved with those of the FBXL10/11demethylases, which are also selective for the di-/mono-methylated lysine states, but differs from that of the JMJD2 demethylases which are selective for tri-/di-methylated states. The results rationalize the lack of activity for the clinically observed F279S PHF8 variant and they will help to identify inhibitors selective for specific N(epsilon)-methyl lysine demethylase subfamilies.
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PMID:Crystal structure of the PHF8 Jumonji domain, an Nepsilon-methyl lysine demethylase. 2006 92

Histone lysine methylation is dynamically regulated by lysine methyltransferases and lysine demethylases. Here we show that PHD finger protein 8 (PHF8), a protein containing a PHD finger and a Jumonji C (JmjC) domain, is associated with hypomethylated rRNA genes (rDNA). PHF8 interacts with the RNA polymerase I transcription machinery and with WD repeat-containing protein 5 (WDR5)-containing H3K4 methyltransferase complexes. PHF8 exerts a positive effect on rDNA transcription, with transcriptional activation requiring both the JmjC domain and the PHD finger. PHF8 demethylates H3K9me1/2, and its catalytic activity is stimulated by adjacent H3K4me3. A point mutation within the JmjC domain that is linked to mental retardation with cleft lip and palate (XLMR-CL/P) abolishes demethylase activity and transcriptional activation. Though further work is needed to unravel the contribution of PHF8 activity to mental retardation and cleft lip/palate, our results reveal a functional interplay between H3K4 methylation and H3K9me1/2 demethylation, linking dynamic histone methylation to rDNA transcription and neural disease.
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PMID:PHF8 activates transcription of rRNA genes through H3K4me3 binding and H3K9me1/2 demethylation. 2020 42