Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.48 (transcriptase)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nitric oxide (NO) is readily oxidized to nitrate and nitrite and NO activates guanylyl cyclase, increasing cyclic GMP levels. To determine if nitric oxide synthase (NOS) is present in urine collected daily from patients following renal transplantation, we evaluated NOS activity in the leukocyte-rich particulate fraction and measured nitrate, nitrite, and cyclic GMP levels in the supernatant fraction of the urine. Reverse transcriptase-PCR and cDNA sequencing confirmed the presence of inducible NOS (iNOS) in cells obtained from the urine of renal transplant patients with rejection. NOS activity was elevated significantly in renal transplant patients with rejection (6.40 +/- 1.47 pmol citrulline/min/mg protein) or with urinary tract infection (29.56 +/- 11.00 pmol citrulline/min/mg protein), when compared to post-renal transplantation patients without rejection or urinary tract infection (0.51 +/- 0.21 pmol citrulline/min/mg protein). Nitrate levels increased in renal transplant patients with rejection and nitrite levels increased in renal transplant patients with urinary tract infection (UTI). Cyclic GMP levels increased with both rejection and UTI. This study demonstrates the presence of NOS activity and inducible NOS-mRNA in cells isolated from the urine of patients undergoing renal allograft rejection.
 ...
PMID:Nitric oxide synthase induction with renal transplant rejection or infection. 894 94

The muscles of the corpus cavernosum of the penis relax in response to stimulation of non-adrenergic, non-cholinergic nerves or nitric oxide (NO)-donating drugs to elicit erection. It is generally assumed that NO mediates this effect via activation of soluble guanylyl cyclase and a subsequent increase in cyclic guanosine 3', 5'-monophosphate concentration. However, there are no data on the expression of this enzyme in human corpus cavernosum. The purpose of the present study was the molecular characterization of NO-sensitive guanylyl cyclase in human corpus cavernosum. RNA was extracted from tissue samples obtained from seven patients undergoing penile prosthetic surgery or correction of penile deviation. Reverse transcriptase-polymerase chain reaction (RT-PCR) with specific primers for the subunits of NO-sensitive guanylyl cyclase was performed, and PCR products were subcloned and sequenced. Specific amplification products encoding the alpha(1), beta(1), alpha(2), and beta(2) subunits were detected. In addition, we isolated a transcript encoding a novel variant beta(2) subunit. To test whether this novel transcript arises by alternative splicing or whether it is encoded by a separate gene, a 4000-bp clone of the corresponding genomic DNA sequence was isolated. Sequence analysis suggests that the novel beta(2) variant arises by alternative splicing from the same gene as the beta(2) subunit on chromosome 13. In conclusion, our findings suggest the presence of different subunit mRNAs of NO-sensitive guanylyl cyclase in human corpus cavernosum.
 ...
PMID:Expression of nitric oxide-sensitive guanylyl cyclase subunits in human corpus cavernosum. 1067 88

Natriuretic peptide binding sites were examined in the gills of the hagfish Eptatretus cirrhatus (Class Agnatha, subfamily Eptatretinae) using radio-ligand binding techniques, molecular cloning and guanylyl cyclase assays. Iodinated rat atrial natriuretic peptide ((125)I-rANP) and iodinated porcine C-type natriuretic peptide ((125)I-pCNP) bound specifically to the lamellar folds and cavernous tissue of E. cirrhatus gills, and 0.3 nmol l(-1) rat ANP competed for 50 % of specific (125)I-rANP binding sites. Affinity cross-linking of (125)I-rANP to gill membranes followed by sodium dodecylsulphate-polyacrylamide gel electrophoresis revealed a single binding site of 150 kDa. In the presence of Mn(2+), 0.1 nmol l(-1) rANP inhibited cGMP production, whereas 1 micromol l(-1) rANP stimulated cGMP production rates. At 1 micromol l(-1), pCNP also stimulated cGMP production. The production of cGMP was also measured in the presence and absence of ATP with either Mn(2+) or Mg(2+). Reverse transcriptase polymerase chain reaction (RT-PCR) of hagfish gill RNA, followed by cloning and sequencing of PCR products, produced a partial cDNA sequence of a natriuretic peptide guanylyl cyclase receptor. The deduced amino acid sequence indicated 87-91 % homology with other natriuretic peptide guanylyl cyclase receptors. This study indicates the presence of a natriuretic peptide guanylyl cyclase receptor in the gills of E. cirrhatus that is similar to the natriuretic peptide guanylyl cyclase receptors in higher vertebrates. These observations demonstrate that the coupling of natriuretic peptide receptors with guanylyl cyclase has a long evolutionary history.
 ...
PMID:Evidence of a guanylyl cyclase natriuretic peptide receptor in the gills of the new zealand hagfish Eptatretus cirrhatus (Class Agnatha). 1093 96