Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P36969 (phospholipid hydroperoxide glutathione peroxidase)
 344 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Genetic lesions causing human male infertility are manifold. Besides gross chromosomal aneuploidies and rearrangements, microdeletions and single gene defects can interfere with male fertility. Male fertility is not only dependent on genes controlling the male germ line but also on genes of the networks functional for male gonad development and male somatic development, respectively. It is popular to unravel these netweorks with mouse gene knock-out mutants displaying reproductive defects. However, substantial arguments can be given for more functional studies directly on the human genes, because multiple reproductive proteins evolve quickly most likely for adopting to the specific needs of the species class. Prominent examples are mutations of the FSHR gene causing different pathologies in mouse and human and the DAZ gene family not found in the mouse genome but in the human genome with an essential male fertility function. Therefore this review is focussed on a comprehensive overview of human genes known with mutations causing male infertility (AR; AZF gene families; CFTR, DM-1, DNAH gene family, FGFR1, FSHR, INSL3, KAL-1, LGR8- GREAT, LHR, POLG). Then some human genes are described well recognised as functional in spermatogenesis and male fertility although gene specific mutations causing infertility were not yet identified (CREM, CDY1, DAZL1, PHGPx, PRM-1, PRM-2). They are designated as "spermatogenesis phase marker" or "male fertility index" genes, because they are useful tools for diagnosing the patient's spermatogenesis disruption phase and for predicting the presence and quality of his mature sperms. Current therapeutic protocols for human male infertility do usually not cure the specific gene defect but try to bypass it using Artificial Reproductive Technology (ART). Putative imprinting defects in the early embryo probably associated with the used ART protocol and an increase of chromosome abnormalities in the ART offspring now strongly asks for a significant improvement of this outcome requesting urgently more basic research on the genes functioning in the human male germ line and during early human embryogenesis.
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PMID:Molecular genetics of human male infertility: from genes to new therapeutic perspectives. 1496 34

PHGPx (phospholipid hydroperoxide glutathione peroxidase) is a selenoprotein present in at least three isoforms in testis: cytosolic, mitochondrial and nuclear. All of these derive from the same gene and are structurally related with the exception of the snPHGPx (sperm nucleus-specific form), which differs from the others due to the presence of an arginine-rich N-terminus. It has been demonstrated recently that this N-terminus is encoded by an alternative exon located in the first intron of the PHGPx gene. The expression of snPHGPx has been attributed either to an alternative pre-mRNA splicing or to the presence of a distinct promoter region. Nevertheless, the exact molecular mechanism by which the expression of snPHGPx occurs has not been demonstrated so far. Preliminary sequence analysis of the region located upstream of the alternative exon revealed some potential DNA-binding sites, one of which is specific to the binding of CREM (cAMP-response element modulator) transcription factors. By using electrophoretic mobility-shift assays, we demonstrated that both nuclear protein extract from highly purified rat spermatid cells and recombinant CREM-tau protein can specifically bind to this element. Furthermore, we cloned a 1059 bp comprising the intron and the alternative exon for snPHGPx in the pCAT3 reporter vector. By transient transfection experiments, we demonstrated that the expression of the transcription factor CREM-tau can induce the activation of the reporter gene in NIH-3T3 cell line. These results were confirmed by chromatin immunoprecipitation experiments performed on highly purified rat spermatid cells. On the basis of these results, we demonstrate that snPHGPx expression is mediated by the transcription factor CREM-tau, which acts as a cis-acting element localized in the first intron of the PHGPx gene.
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PMID:cAMP-response element modulator-tau activates a distinct promoter element for the expression of the phospholipid hydroperoxide/sperm nucleus glutathione peroxidase gene. 1522 22