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)

In several families with non-specific X-linked mental retardation (XLMR) linkage analyses have assigned the underlying gene defect to the pericentromeric region of the X chromosome, but none of these genes have been isolated so far. Here, we report on the cloning and characterization of a novel gene, DXS6673E, that maps to Xq13.1, is subject to X-inactivation and is disrupted in the 5' untranslated region by a balanced X;13 translocation in a mentally retarded female. The DXS6673E gene is highly conserved among vertebrates and its expression is most abundant in brain. It encodes a hydrophilic protein of 1358 amino acids (aa) that does not show sequence homology to other known proteins. A segment of this protein consisting of neutral and hydrophobic aa with a proline residue in every second position may represent a transmembrane domain. Almost complete sequence identity was found between the 3' end of the DXS6673E gene and two expressed sequence tags (ESTs) and between the 5' end of the DXS6673E gene and a third EST. Moreover, weaker sequence similarity was observed between coding regions and two other ESTs.
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PMID:Cloning and characterization of DXS6673E, a candidate gene for X-linked mental retardation in Xq13.1. 881 23

A recently described atypical myeloproliferative disorder is invariably associated with reciprocal translocations involving 8p11-12. The most common rearrangement is a t(8;13)(p11;q11-12). Here we determine that this translocation results in the fusion of the fibroblast growth factor receptor 1 gene (FGFR1), a member of the receptor tyrosine kinase family at 8p11, to a novel gene at 13q11-12 designated RAMP . The predicted RAMP protein exhibits strong homology to the product of a recently cloned candidate gene for X-linked mental retardation, DXS6673E . We also provide the first report of a novel, putative metal-binding motif, present as five tandem repeats in both RAMP and DXS6673E. RT-PCR detected only one of the two possible fusion transcripts, encoding a product in which the N-terminal 641 amino acids of RAMP become joined to the tyrosine kinase domain of FGFR1. Receptor tyrosine kinases are not commonly involved in the formation of tumour-specific fusion proteins. However, the previous reports of involvement of receptor tyrosine kinases in fusion proteins in non-Hodgkin's lymphoma, chronic myelomonocytic leukaemia and papillary thyroid carcinoma described similar rearrangements. By analogy with these, we propose that the RAMP-FGFR1 fusion product will contribute to progression of this myeloproliferative disorder by constitutive activation of tyrosine kinase function.
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PMID:The t(8;13)(p11;q11-12) rearrangement associated with an atypical myeloproliferative disorder fuses the fibroblast growth factor receptor 1 gene to a novel gene RAMP. 949 16

Chromosome 8p11-12 is the site of a recurrent breakpoint in a myeloproliferative disorder that involves lymphoid (T- or B-cell), myeloid hyperplasia and eosinophilia, and evolves toward acute leukemia. This multilineage involvement suggests the malignant transformation of a primitive hematopoietic stem cell. In this disorder, the 8p11-12 region is associated with three different partners 6q27, 9q33, and 13q12. We describe here the molecular characterization of the t(8;13) translocation that involves the FGFR1 gene from 8p12, encoding a tyrosine kinase receptor for members of the fibroblast growth factor family, and a gene from 13q12, tentatively named FIM (Fused In Myeloproliferative disorders). FIM is related to DXS6673E, a candidate gene for X-linked mental retardation in Xq13.1; this defines a gene family involved in different human pathologies. The two reciprocal fusion transcripts, FIM/FGFR1 and FGFR1/FIM are expressed in the malignant cells. The FIM/FGFR1 fusion protein contains the FIM putative zinc finger motifs and the catalytic domain of FGFR1. We show that it has a constitutive tyrosine kinase activity.
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PMID:Fibroblast growth factor receptor 1 is fused to FIM in stem-cell myeloproliferative disorder with t(8;13). 957 49

Tandem repeats of a novel, putative, zinc-binding motif (MYM) have been described within the products of two, highly homologous genes: ZNF198/RAMP/FIM and ZNF261/DXS6673E. ZNF198, mapping to 13q11-q12, was recently shown to fuse to the fibroblast growth factor receptor 1 gene in the t(8;13)(p11;q11-q12) rearrangement associated with a stem cell leukemia/lymphoma syndrome. ZNF261 at Xq13.1 is disrupted by a t(X;13)(q13.1;q32) rearrangement in a mentally retarded patient and is a candidate gene for nonspecific X-linked mental retardation. Here we have cloned another member of this family, designated ZNF258, and mapped it to chromosome band 14q12. In addition, ZNF262/KIAA0425 was identified as a further member of the family and mapped to 1p32-p34. The predicted protein products of ZNF258 and ZNF262 maintain the repeats of the MYM motif. Isolation of these new members will facilitate the functional characterization of the MYM family and motif.
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PMID:Cloning and mapping of members of the MYM family. 1048 18

DXS6673E is a candidate gene for nonspecific X-linked mental retardation and encodes a novel Zn-finger protein. The ortholog murine gene DXHXS6673E in XC-D was isolated and characterized. It is ubiquitously expressed in all embryonic stages and adult tissues. Two different transcription start sites exist that result in two major transcripts of 6055 and 5352 nucleotides, each composed of 25 exons. Exon 1A is tissue specific, whereas exon 1B is transcribed constitutively. Both variants are translated into the same 1370-amino-acid protein. Transcripts are subject to alternative splicing at the 5'-end. Some of the isoforms are developmental stage and tissue specific. Among them, one was present only in embryos and adult brain. Sequence analysis demonstrated evolutionary conservation down to the arthropods and defined several conserved protein motifs. Subcellular localization studies with green fluorescent protein as a reporter showed that DXS6673E is predominantly located in the nucleus due to several functional nuclear localization signals. Three distinct protein distribution patterns in COS-7 cells could be identified.
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PMID:DXS6673E encodes a predominantly nuclear protein, and its mouse ortholog DXHXS6673E is alternatively spliced in a developmental- and tissue-specific manner. 1066 51