Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.1 (RNase)
 16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The rat hst70 gene belongs to a heat shock hsp70 multigene family and its expression has been detected so far solely in spermatocytes. To investigate the cis-elements responsible for testis-specific expression of the hst70 gene we produced several lines of transgenic mice carrying fragments of the 5'-flanking regions of the hst70 gene fused to the chloramphenicol acetyltransferase (CAT) reporter gene. Hybrid genes of series B were constructed such that, besides the 780 bp, 343 bp and 163 bp 5'-flanking region these plasmids contained no other sequences of the hst70 gene. In hybrid genes of series D the CAT gene was ligated to 343 bp and 252 bp 5'-flanking regions together with the 57 bp of the 5'-end nontranslated (leader) sequences of the hst70 gene. We found that in 780/B, 343/B, 343/D and 252/D adult mice the transgene was specifically and highly expressed in testes. In developing testes the high CAT activity appeared in transgenic mice aged 3 weeks and older. None of the three 163/B transgenic lines exhibited CAT activity in any tissue analyzed. In all CAT expressing lines a weak but significant CAT activity (up to 5% of that in testis) was detected also in the brain. RNase protection assay confirmed that the endogenous hst70 gene transcripts are present in testis as well as in brain of nontransgenic rats and mice. Our data show that the cis-regulatory sequences responsible for testis-specific and developmentally regulated expression of the hst70 gene are localized within the 252 bp region 5' to the gene and neither the 5'-end nor 3'-end nontranslated sequences of the gene are important for this specificity.
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PMID:A 252 bp upstream region of the rat spermatocyte-specific hst70 gene is sufficient to promote expression of the hst70-CAT hybrid gene in testis and brain of transgenic mice. 749 63

Androgens are known to exert a variety of effects on an organism while follicle-stimulating hormone (FSH) seems to act specifically on the gonads. To investigate whether these effects are reflected by the expression pattern of the androgen receptor (AR) or the FSH receptor (FSHR) we screened 38 different tissues and organs of one intact and one castrated male non-human primate (Macaca fascicularis). By means of a highly sensitive ribonuclease protection assay (RPA) we demonstrated AR mRNA expression in all tissues of the intact monkey investigated. Immunohistochemistry of selected organs from this monkey revealed a good correlation between AR mRNA and protein expression. In the castrated monkey, the overall AR mRNA expression was markedly lower compared with the intact monkey, although higher expression was present in the pituitary, thyroid and prostate glands. FSHR mRNA was only detected in testicular tissue. This study has revealed, for the first time, ubiquitious expression of the AR mRNA in a non-human primate. The testis-specific expression of the FSHR highlights the importance of FSH for spermatogenesis with the testis being apparently the only target organ.
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PMID:Ubiquitous expression of the androgen receptor and testis-specific expression of the FSH receptor in the cynomolgus monkey (Macaca fascicularis) revealed by a ribonuclease protection assay. 757 19

cDNA clones encoding the testis-specific form of the rat pyruvate dehydrogenase complex E1 alpha subunit have been isolated. Comparison of the predicted amino acid sequence with those of the somatic and testis-specific E1 alpha forms of man and mouse and the somatic E1 alpha form of rat indicates the change of a serine residue, believed to be phosphorylated in vivo by pyruvate dehydrogenase E1 alpha-specific kinase, to an alanine at position 233. The implications of this change are discussed. Northern blot analysis and RNase protection assays indicate that the expression of mRNA encoding testis-specific E1 alpha subunit is restricted to testis whereas mRNA for the somatic form is found in all tissues analyzed, albeit in very small amounts in testis.
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PMID:Characterization of cDNAs encoding the rat testis-specific E1 alpha subunit of the pyruvate dehydrogenase complex: comparison of expression of the corresponding mRNA with that of the somatic E1 alpha subunit. 791 43

Experimental allergic orchitis (EAO) can be induced actively and passively in mice by either immunization with mouse testicular homogenate (MTH) in conjunction with the appropriate adjuvants or by transferring CD4+ T cells isolated from sensitized donors into non-immunized, naive recipients. The distribution of inflammatory lesions seen in active and passive EAO are markedly different. In active EAO maximal disease is observed in the seminiferous tubules, whereas in passive EAO lesions occur primarily in the straight tubules, rete testis, and ductus efferentes. These observations suggest that different immunopathogenic mechanisms and/or aspermatogenic autoantigens may be responsible for the distinct histopathologic profiles. Two murine testis-specific aspermatogenic autoantigens (mAP1 and mAP2) were partially purified from MT acetone powder by extraction in 7-M urea under reducing conditions, gel filtration, ion-exchange chromatography, and preparative isoelectric focusing from pH 3 to 10. In gel filtration on Sephacryl S-400 in 7-M urea, mAP1 is confined to the V0 peak, while mAP2 is in the major included peak. mAP1 has an isoelectric point of 4.4-4.9, is sensitive to both pronase and DNase but not RNase, and is active at a minimal dose of 250-500 micrograms (dry wt). Dose-response bioassays for active and passive EAO revealed that mAP1 preferentially elicits active disease, whereas mAP2 is most effective at eliciting passive disease. These results support the concept that the different histopathologic profiles seen in active and passive EAO are, in part, the result of different immunopathologic responses elicited by separate aspermatogenic autoantigens.
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PMID:Experimental allergic orchitis in mice. VII. Preliminary characterization of the aspermatogenic autoantigens responsible for eliciting actively and passively induced disease. 799 75

The structure of the gene encoding the human testis-specific isozyme of lactate dehydrogenase (LDH) has been characterized and a regulatory region identified by promoter activity. The single-copy ldh-c gene has two alternative 5' noncoding exons and seven coding exons comprising an approximately 40-kb locus. The gene does not contain the canonical TATA or CAAT promoter sequences, and ribonuclease protection experiments suggest multiple transcription start sites. In the present study an immortalized murine germ cell line was used to detect promoter activity driven by 5' sequence of human ldh-c with lacZ as the reporter gene. Reporter gene activity was nondetectable when promoter constructs were transfected into nongerminal cells.
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PMID:Genomic structure and promoter activity of the human testis lactate dehydrogenase gene. 831 84

The differential regulation of somatic and testis-specific cytochromes c during spermatogenesis in the mouse is accompanied by changes in mRNA length (Hake, L. E., Alcivar, A. A., and Hecht, N. B. (1990) Development 110, 249-257). In spermatogenic stem cells through early meiotic cells, we detect four somatic cytochrome c (cyt cs) mRNAs of 1.3, 1.1, and 0.7-0.5 kilobases (kb), whereas in postmeiotic cells we detect a larger cyt cs mRNA of 1.7 kb. Oligonucleotide-directed RNase H cleavage of cyt cs mRNA revealed that the 1.7-kb mRNA contains over 1 kb of 5'-untranslated region which is not present in the four shorter cyt cs mRNAs. RNase protection assays indicate that this additional sequence arises from the utilization of an alternative transcription initiation site of the functional cyt cs gene which is 1085 base pairs upstream of the initiation site for the four shorter cyt cs mRNAs. To analyze the promoter for the 1.7-kb mRNA, a genomic clone containing the cyt cs gene and 5 kb of 5'-flanking DNA was isolated. Sequence comparison of the putative promoter region with promoters of other postmeiotically expressed genes reveals several conserved regions. Utilization of this alternative initiation site may be involved in the down-regulation of cytochrome cs during spermatogenesis.
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PMID:Utilization of an alternative transcription initiation site of somatic cytochrome c in the mouse produces a testis-specific cytochrome c mRNA. 838 25

The gene encoding the TATA-binding protein, TBP, is highly overexpressed during the haploid stages of spermatogenesis in rodents. RNase protection analyses for mRNAs containing the previously identified first, second, and eighth exons suggested that most TBP mRNAs in testis did not initiate at the first exon used in somatic cells (here designated exon 1C). Using a sensitive ligation-mediated cDNA amplification method, 5' end variants of TBP mRNA were identified, and the corresponding cDNAs were cloned from liver and testis. In liver, a single promoter/first exon is used to generate a steady-state level of roughly five molecules of TBP mRNA per diploid cell equivalent. In testis, we detect modest up-regulation of the somatic promoter and recruitment of at least five other promoters. Three of the alternative promoter/first exons, including 1C and two of the testis-specific promoter/first exons, 1D and 1E, contribute roughly equivalent amounts of mRNA which, in sum, account for greater than 90% of all TBP mRNA in testis. As a result, round spermatids contain an estimated 1000 TBP mRNA molecules per haploid cell. Testis TBP mRNA also exhibits several low abundance 5' end splicing variants; however, all detected TBP mRNA leader sequences splice onto the common exon 2 and are expected to initiate translation at the same site within exon 2. The precise locations of the three major initiation exons are mapped on the gene. The identification of the strong testis-specific promoter/first exons will be important for understanding spermatid-specific tbp gene regulation.
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PMID:Spermatid-specific overexpression of the TATA-binding protein gene involves recruitment of two potent testis-specific promoters. 903 Jun 7

Hormone-sensitive lipase (HSL) catalyses the rate-limiting step of adipose tissue lipolysis. The human HSL gene is composed of nine exons encoding the adipocyte form and a testis-specific coding exon. Northern blot analyses showed that human adipocytes express a 2.8 kb HSL mRNA, suggesting the presence of a short (20-150 bp) 5' untranslated region (5'-UTR). A single 5'-UTR of approx. 70 nt was detected in RNase H mapping experiments. Two 5'-UTRs of 70 and 170 nt respectively were obtained by rapid amplification of cDNA ends and cDNA library screenings. RNase protection experiments, with probes derived from the two products, showed that human adipocyte HSL mRNA contains only the 70 nt product. Primer extension analysis mapped the transcriptional start site 74 nt upstream of the start codon. In HT29, a human cell line expressing HSL, the presence of the short or the long 5'-UTR is mutually exclusive. The short and long 5'-UTR exons were located 1.5 and approx. 13 kb respectively upstream of the first coding exon. Various portions of the 5'-flanking region upstream of the short product exon were linked to the luciferase gene and transfected into cells that express HSL (HT29 cells and rat adipocytes) and do not express HSL (HeLa cells). High luciferase activity was found for constructs containing the sequence between nt -2400 and -86, but not for shorter constructs. An analysis of 14 kb of genomic sequence revealed the presence of five DNase I hypersensitive sites associated with active gene transcription. Three of the sites are located in the vicinity of the transcriptional start site and could be linked to the minimal promoter activity. Two of the sites are located downstream of the exon containing the start codon, suggesting the presence of intronic regulatory elements.
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PMID:Characterization of the promoter of human adipocyte hormone-sensitive lipase. 937 1

Cloning and sequencing of the chicken prolactin receptor (PRLR) gene segment from the transmembrane domain to the box 2 motif revealed the presence of the two testis-specific first exons, TSE-1 and TSE-2, encoding the unique 5'-end sequences of the reported and newly identified multiple 5'-truncated PRLR transcripts containing only the cytoplasmic domain in the testis. TSE-1 was located downstream of the exon encoding the transmembrane domain and TSE-2 presented downstream of the exon encoding the box 1 motif. These findings indicate that the box 1-containing 5'-truncated transcripts are generated by the utilization of TSE-1 as the first exon with distinct splicing donor sites to the box 1-containing exon, and that the utilization of TSE-2 as the first exon and its splicing to the box 2-containing exon results in the generation of the box 1-lacking transcript. Three transcription initiation sites for the box 1-containing 5'-truncated transcripts and two transcription initiation sites for the box 1-lacking transcript were detected by the RNase protection assays. Reverse transcription-polymerase chain reaction analysis showed that the expression levels of all these 5'-truncated PRLR transcripts are simultaneously increased during sexual maturation, accompanying the decrease of the amount of the canonical full-length transcript for PRLR.
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PMID:Two novel first exons in the prolactin receptor gene are transcribed in a tissue-specific and sexual maturation-dependent manner to encode multiple 5'-truncated transcripts in the testis of the chicken. 1076 May 91

Heterogeneous nuclear ribonucleoproteins (hnRNPs) A2 and B1 are abundant nuclear proteins that bind to nascent RNAs synthesized by RNA polymerase II. Previously we had found that the splicing isoforms hnRNP B0a/b, from which the ninth exon of the A2/B1 gene is excluded, are abundantly expressed in testis. We postulated that B0a/b are testis-specific isoforms, and investigated the expression of A2/B1 and B0a/b in rat tissues and in postnatal development of rat testes using RNase protection assay, immunoblotting, and immunohistochemistry. We found that hnRNP B0a/b mRNAs are expressed in several tissues but that the testis alone expresses B0a/b proteins. A sequential study using neonatal rat testes demonstrated that B0a/b mRNAs are produced after 17 days of age, but not translated until 4 weeks of age when round spermatids appear in addition to spermatogonia and spermatocytes. Immunohistochemically, hnRNP A2/B1 isoforms are expressed during spermatogenesis from spermatogonia through round spermatids, whereas the expression of A1 is restricted to spermatogonia. This expression pattern in the rat testis is maintained from birth through adulthood. These results suggest that the expression of the hnRNP A2/B1 gene is partly regulated by a testis-specific post-transcriptional mechanism, and that the products of the A2/B1 gene, especially hnRNP B0a/b, are involved in spermatogenesis.
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PMID:Testis- and developmental stage-specific expression of hnRNP A2/B1 splicing isoforms, B0a/b. 1097 4


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