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

We have previously characterized a family of transcripts, isolated from bovine placental tissue, that are related to prolactin (PRL) and are distinct from placental lactogen (PL). Here we describe a PRL-related gene that corresponds to one of these placental transcripts, bPRC-I. Restriction endonuclease mapping and sequence analysis of this gene reveal that it is distributed among five exons spanning approximately 9.2 kb. The site of transcription initiation was determined and repetitive sequences were localized in the first two introns. The nucleotide sequence of the coding region is 64% homologous to the bPRL gene and 44% homologous to the bovine growth hormone (bGH) gene. The 5'-flanking region shows no detectable homology to that of bPRL or bGH. Genomic Southern blot analysis indicates that this gene is a member of a family of PRL-related genes.
 ...
PMID:Characterization of the gene corresponding to bovine placental prolactin-related cDNA I: evolutionary implications. 272 68

The gene deletions responsible for isolated partial deficiency of fetal human chorionic somatomammotropin (hCS) production were characterized by restriction endonuclease analysis of genomic DNA prepared from the leukocytes of an affected child. The phenotypically normal child was the product of a 38-week pregnancy characterized by peak maternal hCS levels of 1.1 micrograms/microliter (normal, 3-9.2 micrograms/ml) and normal levels of other pregnancy-associated hormones. Two genes, termed hCS-A and hCS-B, specify the same mature hCS peptide and are responsible for fetal hCS production. Digestion of the child's DNA with the enzymes Hind III, Eco RI, Bam HI, Bgl II, Hinc II and Msp I disclosed absence of the restriction fragments that normally contain the hCS-A gene. However, the hCS-B gene was present in the child's DNA. The child's DNA digests contained an abnormally large Eco RI fragment of 10.0 kb containing the hCS-L gene. This abnormal fragment is a marker for a deletion that is responsible for complete deficiency of hCS when present in the homozygous state. The child's DNA restriction patterns were consistent with heterozygosity for two different deletions involving hCS genes. The paternal hGH gene cluster lacked the hCS-A, human GH variant, and hCS-B genes, while the maternal cluster lacked only the hCS-A gene. Thus, the child's DNA contained only one of the normal complement of four functional hCS genes per diploid genome. Material hCS levels approximately one fourth as great as those present at comparable stages of normal pregnancies indicated that there was no compensatory increase in expression of the remaining hCS gene.
 ...
PMID:An effect of gene dosage on production of human chorionic somatomammotropin. 298 39

Human placental lactogen (hPL) and growth hormone (hGH) are two hormones thought to have evolved from a common ancestral gene (along with prolactin), yet they have quite different functions and specificities. The nucleic acid sequences of the respective cDNAs of the two genes share considerable homology, as well as the existence of multiple forms of each gene within the genome. In this study we report on the linkage arrangement of several genes from this group. Two hPL-like genes as well as an hGH gene are shown to be linked within a 38-kilobase pair region of DNA. Linkage between a variant hGH gene and an hPL gene is also shown. The orientation and structural organization of these genes was previously established using 5'- and 3'-specific probes from a placental lactogen cDNA clone and detailed restriction endonuclease mapping. Restriction fragments from the overlapping clones were verified by comparison to digests of high molecular weight genomic DNA. In addition, the location of a specific class of repetitive DNA sequences, the Alu family, was mapped on these clones using the recombinant clone BLUR 8. All members of this multigene family have Alu repeat sequences either immediately flanking their 3' or 5' untranslated regions or within their intervening sequences.
 ...
PMID:Linkage arrangement of human placental lactogen and growth hormone genes. 628 68

Experiments were designed to determine if the members of the human placental lactogen (hPL) cluster, consisting of four nonallelic genes, are transcribed in term placenta. Taking advantage of differences in restriction endonuclease sites in the coding portions of the different hPL genes and thus of their putative cDNAs, we have identified two transcriptionally active nonallelic hPL genes in term placenta. The two expressed genes, which code for secreted hPL with identical amino acid sequences, are about equally represented in the hPL mRNA population.
 ...
PMID:Two structurally different genes produce the same secreted human placental lactogen hormone. 630 56

The human growth hormone variant (GH-V) gene is expressed during pregnancy in the syncytiotrophoblast and, as shown recently, in the normal human testis. In addition to the classical transcript encoding for the 22 K major form, intron D-retaining processed mRNAs (GH-V2) have also been described in both tissues. In the present study we analyzed testicular GH-V RNA alternative splicing patterns, a major source of GH variability. We observed three types of GH-V-derived mRNAs by reverse transcription-polymerase chain reaction amplification of GH/placental lactogen mRNA, subsequent cloning into appropriate vectors, vector amplification, restriction-endonuclease map-analysis and double-strand sequencing of GH-V clones. Apart from the conventional splice product encoding classical hGH-V (22K, 191 amino acids (aa)) and intron D-retaining mRNA GH-V2 (230aa), we detected an additional GH-V mRNA variant, GH-Vdelta4, utilizing a competitive splice-donor site 4 bp 5'of the conventional exon 4/intron D splice-donor site, but retaining the genuine intron D/exon 5 splice-acceptor site. This mRNA encodes a putative 25 K protein of 219 amino acids in length, having the first 124 amino acids and, thus, two and a half structural alpha-helices in common with hGH-V.hGH-Vdelta4 has lost the N-glycosylation site at Asn 140 of hGH-V, but acquires a novel site at position 148 as well as a cystein-rich domain in the 65 carboxyl-terminal amino acids, potentially involved in multiple disulfide-bridge formation. Tissue specificity and possible functions for testicular physiology remain to be investigated.
 ...
PMID:Complex alternative splicing of the GH-V gene in the human testis. 982 Jun 9