Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The organization and sequence of the rat preprolactin gene has been investigated. Analysis of two different plasmids containing pituitary cDNA inserts has provided the complete 681-nucleotide coding sequence of preprolactin as well as 17 nucleotides preceding the initiation codon and 90 nucleotides following the termination codon. Digestion of rat chromosomal DNA with the restriction endonuclease Eco RI followed by size fractionation and hybridization to a labeled prolactin cDNA probe has demonstrated that prolactin genomic sequences are located on 6.0-, 3.9-, and 2.9-kilobase fragments. The 6.0- and 3.9-kilobase fragments were isolated from a library of cloned rat DNA fragments. The sequence of more than 1800 nucleotides of the cloned DNA has been determined. The sequenced region contains coding regions of 180 and 189 nucleotides which specify the COOH-terminal 123 amino acids of the 227-amino-acid sequence of rat preprolactin. These coding regions are separated by an intervening sequence of 597 nucleotides. At least one other large intervening sequence separates this region from the region coding for the NH2-terminal portion of preprolactin. Hybridization experiments suggested that the intervening sequences of the rat prolactin gene contain DNA sequences which are repeated elsewhere in the rat genome.
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PMID:Structure of the rat prolactin gene. 625 Oct 61

Prolactin (PRL) and growth hormone (GH) genes derive from a common ancestor and still share some sequence homologies. Their expression in the pituitary gland is regulated in opposite directions by most of the many hormones acting on them. This provides an interesting system to study sequences involved in gene expression. Using a human PRL cDNA clone as a probe, we screened a human genomic DNA library in lambda phage and isolated a single recombinant comprising the whole hPRL gene. It was characterized by restriction endonuclease mapping and cDNA hybridization, by DNA heteroduplex analysis and by nucleotide sequencing. The hPRL gene is present as a single copy per haploid genome, is approximately 10 kb long and contains four introns, three of which interrupt the coding sequence at the same locations as in the known GH and PRL genes. The origin of transcription was determined by S1 mapping on prolactinoma mRNAs. The search for direct and inverted repeats, as well as dyad symmetries was carried out in the 900-bp sequenced in the 5'-flanking region. Sequence homologies between hPRL, hGH and rPRL were derived from computer drawn matrices for these upstream regions.
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PMID:Isolation and characterization of the human prolactin gene. 632 71

The human (h) protein hormones, growth hormone (hGH-N) and prolactin (hPRL), are mainly produced in the pituitary, whereas the human placenta expresses the other four members of the protein hormone gene family, designated placental lactogens (PL-A, PL-B, PL-L) and growth hormone variant (GH-V), GH-N stimulates somatic growth, supports nitrogen-, phosphate- and potassium retention and promotes lipolytic and anabolic metabolism, whereas PRL acts on the mammary gland and induces mammogenesis, lactogenesis and galactopoesis. Both hyperprolactinemia and growth hormone deficiency affect the onset of puberty and reproduction in man and mice. In addition to the glycoprotein hormones, these hormones play a role in the maintenance of testicular function. Our group previously demonstrated eutopic production of glycoprotein hormones hLH (human luteinizing hormone) and hCG (human chorionic gonadotropin) in the testis. We have now extended our investigations to the local testicular expression of protein hormones. By means of the molecular biology techniques of the reverse transcription-polymerase chain reaction (RT-PCR), Southern blot and by restriction endonuclease analyses of the generated PCR products we demonstrated the eutopic expression of genes coding for the protein hormones. GH-N gene transcripts were detected only in the pituitary and abundant PL-A/B and a few GH-V gene transcripts were demonstrable in the placenta. In contrast, in the testis GH/PL and PRL genes are transcribed. Since testicular protein hormone gene expression is rather low, these hormones may act locally and not as systemic factors; they presumably modulate the LH/CG-mediated testosterone biosynthesis and/or may act on the spermatogenesis.
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PMID:[The testis as eutopic production site of human growth hormone, placental lactogen and prolactin: possible autocrine/paracrine effects on testicular function]. 899 85