Molecular cloning and chromosomal mapping of DNA rearranged with the parathyroid hormone gene in a parathyroid adenoma.

Parathyroid adenomas are common benign neoplasms for which no chromosomal defects have been described. We recently found two parathyroid adenomas bearing clonal restriction fragment abnormalities involving the PTH locus, and now show that in one of these tumors: (a) a DNA rearrangement occurred at the PTH locus; (b) the rearrangement separated the PTH gene's 5' flanking region from its coding exons, conceivably placing a newly adjacent gene under the influence of PTH regulatory elements; (c) the DNA that recombined with PTH normally maps to 11q13, the known chromosomal location of several oncogenes and the gene for multiple endocrine neoplasia type I; and (d) the rearrangement was a reciprocal, conservative recombination of the locus on 11q13 (Human Gene Mapping Library assignment D11S287) with PTH (on 11p15). These data provide molecular cytogenetic evidence for the clonal occurrence of a major chromosome 11 aberrancy in this benign parathyroid tumor. The D11S287 clone could prove useful in genetic linkage analyses, in determining precise 11q13 breakpoints in other neoplasms, and in identifying a gene on chromosome 11 that may participate in parathyroid tumor development.

Two chromosomal locations for human ornithine decarboxylase gene sequences and elevated expression in colorectal neoplasia.

The polyamines are known to be essential for cellular proliferation. Ornithine decarboxylase (ODC) is a rate-limiting enzyme in the synthesis of these amines, and activity is elevated in colorectal tumors and polyps. Two ODC genes (designated ODC1 and ODC2) were localized by somatic cell hybridization and in situ techniques to 2p25 and 7q31-qter, respectively. Investigation of the expression of ODC in colorectal neoplasia reveals a consistent increase in mRNA expression compared with normal adjacent mucosa and control mucosa, ranging from 1.3- to 12.2-fold. No amplification of the loci was seen. Comparison of ODC mRNA expression with ODC activity from the same samples revealed no direct correlation, suggesting that regulation of ODC in this system occurs at the posttranscriptional level.

Polymorphic human insulin-responsive glucose-transporter gene on chromosome 17p13.

Glucose uptake by heart, skeletal muscle, and adipose tissue is acutely regulated by insulin, which stimulates facilitative glucose transport, at least in part, by promoting the translocation of transporters from an intracellular pool to the plasma membrane. cDNAs encoding the major human insulin-responsive glucose transporter have been isolated and indicate that the insulin-responsive glucose transporter expressed by heart, skeletal muscle, and adipose tissue is a 509-amino acid protein having 65.3, 54.3, and 57.5% identity with the erythrocyte/HepG2, liver, and fetal muscle glucose transporters, respectively. The gene encoding the insulin-responsive glucose transporter (designated GLUT4) was mapped to the p11----p13 region of the short arm of human chromosome 17 by analyzing its segregation in a panel of reduced human-mouse somatic cell hybrids. In situ hybridization to prometaphase chromosomes indicated that GLUT4 was in band p13. A common two-allele restriction-fragment-length polymorphism (RFLP) was identified with Kpn I, and linkage of this RFLP to other polymorphic DNA markers in this region of chromosome 17 provides a set of probes that will be useful for examining the role of this gene in the pathogenesis of diabetes mellitus.

Polymorphic human glucose transporter gene (GLUT) is on chromosome 1p31.3----p35.

The glucose transporter is a membrane glycoprotein that is involved in the uptake of glucose by most, if not all, animal cells. A cloned cDNA that encodes the human protein was used to map the gene to a specific chromosomal region and to identify a DNA polymorphism. The human gene (designated GLUT) was assigned to chromosome 1p31.3----p35 by hybridization of the probe to DNA from a panel of human-mouse somatic cell hybrids containing different human chromosomes and by in situ hybridization to isolated metaphase chromosomes. The most likely location of GLUT is in 1p33. A common two-allele restriction-fragment-length polymorphism was identified with Xba I.

Gastric inhibitory polypeptide: structure and chromosomal localization of the human gene.

Gastric inhibitory polypeptide (GIP) is a 42-amino-acid hormone which may have a role in the regulation of insulin secretion. The characterization of cDNA clones encoding this hormone indicates that it is derived by proteolytic processing of a 153-amino-acid precursor. The human gene coding for the human GIP precursor spans approximately 10 kilobase pairs and consists of six exons. Similar to genes encoding other members of the glucagon superfamily, each exon appears to encode a distinct region of the GIP precursor or its mRNA. The promoter region of the human GIP gene contains potential binding sites for a number of transcriptional factors including Sp 1, AP-1, and AP-2. The human GIP gene has been assigned to chromosome 17q21.3----q22.

Human islet amyloid polypeptide gene: complete nucleotide sequence, chromosomal localization, and evolutionary history.

The gene-encoding human islet amyloid polypeptide (hIAPP), a recently discovered 37 amino acid hormone-like polypeptide which is expressed in the insulin-producing beta-cells of the endocrine pancreas, has been isolated and characterized. The coding region of the gene is interrupted in the 5'-untranslated region and NH2-terminal propeptide by introns of 330 and 4808 base pairs (bp), respectively. Exon 1 (104 bp) encodes most of the 5'-untranslated region of the mRNA; exon 2 (95 bp) encodes 15 nucleotides of 5'-untranslated region, the putative 22 amino acid signal peptide and five residues of the NH2-terminal propeptide; exon 3 (1246 bp) encodes the remainder of the NH2-terminal propeptide (residues 6-9), the IAPP moiety and its processing signals and the 16 amino acid COOH-terminal propeptide, as well as the 3'-untranslated region of the mRNA (1059 bp). Analysis of the nucleotide and predicted amino acid sequence of intron 2 of the hIAPP gene did not reveal any homology with the structurally related calcitonin/calcitonin-gene-related peptide genes and indicated that, in contrast to these latter genes, the hIAPP gene apparently gives rise to only a single hormonal product. The transcriptional initiation site was identified about 28 bp downstream from a TATAA sequence. The hIAPP gene was localized to the p12.3 region of chromosome 12.

Exon-intron organization, expression, and chromosomal localization of the human motilin gene.

The human motilin gene has been isolated and characterized. The gene spans about 9 kilobase pairs (kb) and the 0.7 kb motilin mRNA is encoded by five exons. The 22-amino-acid motilin sequence is encoded by exons 2 and 3. The human motilin gene was mapped to the p21.2----p21.3 region of chromosome 6 by hybridization of the cloned cDNA to DNAs from a panel of reduced human-mouse somatic cell hybrids and by in situ hybridization to human prometaphase chromosomes. RNA blotting using RNA prepared from various regions of the human gastrointestinal tract revealed high levels of motilin mRNA in duodenum and lower levels in the antrum of the stomach; motilin mRNA could not be detected by this procedure in the esophagus, cardia of the stomach, descending colon or gallbladder.

Assignment of beta-hexosaminidase A alpha-subunit to human chromosomal region 15q23----q24.

Tay-Sachs disease results from a mutation in the alpha subunit of beta-hexosaminidase. Using a cDNA clone, we have mapped the gene to 15q23----q24 by in situ hybridization.

Human genes for insulin-like growth factors I and II and epidermal growth factor are located on 12q22----q24.1, 11p15, and 4q25----q27, respectively.

The genes coding for insulin-like growth factors I and II and epidermal growth factor have been localized to human chromosomes 12q22----q24.1, 11p15, and 4q25----q27, respectively.

Assignment of the pepsinogen gene complex (PGA) to human chromosome region 11q13 by in situ hybridization.

The genes coding for human pepsinogen (PGA3, PGA4, and PGA5) were assigned to chromosome region 11q13 by in situ hybridization. Previously we localized the PGA gene complex to a centromeric region of chromosome 11 (p11----q13) by Southern blot analysis of mouse-human somatic cell hybrids. Our in situ hybridization results confirm this assignment and further localize the genes to a smaller region on the long arm.

The gene for human carbonic anhydrase II (CA2) is located at chromosome 8q22.

The gene CA2 for the human carbonic anhydrase II isozyme is encoded in band q22 of chromosome 8. These data and supporting evidence predict that the genes for carbonic anhydrase I and III are also physically closely linked in this chromosomal region.

The human basic fibroblast growth factor gene (FGFB) is assigned to chromosome 4q25.

In situ hybridization was used to localize a cDNA probe for the basic fibroblast growth factor gene (FGFB) to human metaphase and prometaphase chromosomes. In this communication we report the localization of this gene to 4q25.

Cloning of human lysyl hydroxylase: complete cDNA-derived amino acid sequence and assignment of the gene (PLOD) to chromosome 1p36.3----p36.2.

Lysyl hydroxylase (EC 1.14.11.4), an alpha 2 dimer, catalyzes the formation of hydroxylysine in collagens by the hydroxylation of lysine residues in peptide linkages. A deficiency in this enzyme activity is known to exist in patients with the type VI variant of the Ehlers-Danlos syndrome, but no amino acid sequence data have been available for the wildtype or mutated human enzyme from any source. We report the isolation and characterization of cDNA clones for lysyl hydroxylase from a human placenta lambda gt11 cDNA library. The cDNA clones cover almost all of the 3.2-kb mRNA, including all the coding sequences. These clones encode a polypeptide of 709 amino acid residues and a signal peptide of 18 amino acids. The human coding sequences are 72% identical to the recently reported chick sequences at the nucleotide level and 76% identical at the amino acid level. The C-terminal region is especially well conserved, a 139-amino-acid region, residues 588-727 (C-terminus), being 94% identical between the two species and a 76-amino-acid region, residues 639-715, 99% identical. These comparisons, together with other recent data, suggest that lysyl hydroxylase may contain functionally significant sequences especially in its C-terminal region. The human lysyl hydroxylase gene (PLOD) was mapped to chromosome 1 by Southern blot analysis of human-mouse somatic cell hybrids, to the 1p34----1pter region by using cell hybrids that contain various translocations of human chromosome 1, and by in situ hybridization to 1p36.2----1p36.3. This gene is thus not physically linked to those for the alpha and beta subunits of prolyl 4-hydroxylase, which are located on chromosomes 10 and 17, respectively.

Human collagen gene COL5A1 maps to the q34.2----q34.3 region of chromosome 9, near the locus for nail-patella syndrome.

Type V collagen is a fibrillar collagen that is widely distributed in tissues as a minor component of extracellular matrix and is usually composed of one pro alpha 2 (V) and two pro alpha 1 (V) chains. In this report, recently isolated cDNA and genomic clones, which encode the pro alpha 1 (V) chain, are used as probes for hybridization to filter-bound DNA from a panel of human-mouse hybrid cell lines and for in situ hybridization to metaphase chromosomes. These studies establish the chromosomal location of the COL5A1 gene, which encodes the pro alpha 1 (V) chain, within segment 9q34.2----q34.3. These findings add to the previously characterized dispersion of collagen genes in the human genome, as this is the first example of a collagen locus on chromosome 9. In addition, these studies place COL5A1 near the locus for the genetic disorder, nail-patella syndrome (hereditary osteo-onychodysplasia), which also maps to 9q34.

The genes for the lipopolysaccharide binding protein (LBP) and the bactericidal permeability increasing protein (BPI) are encoded in the same region of human chromosome 20.

The lipopolysaccharide binding protein is an acute-phase reactant produced during gram-negative bacterial infections. The bactericidal/permeability increasing protein is associated with human neutrophil granules and has bactericidal activity on gram-negative organisms. In addition to their functional relationship, both proteins share extensive structural similarity. This article demonstrates that the genes for both proteins are in the same region of human chromosome 20, between q11.23 and q12.

Localization of the human collagen gene COL7A1 to 3p21.3 by fluorescence in situ hybridization.

An 8-kb genomic probe, containing 34 collagen-encoding exons, was localized to 3p21.3 by fluorescence in situ hybridization. The genomic probe encoded a previously uncharacterized carboxyl terminal portion of the alpha 1(VII) collagen chain. This mapping result confirms the previous assignment of the alpha 1(VII) gene (COL7A1) to 3p21 and offers a finer subregional localization than was previously available.

Cloning and expression of the murine gene and chromosomal location of the human gene encoding N-acetylglucosaminyltransferase I.

A mouse cDNA clone previously isolated from an F9 teratocarcinoma cell library and shown to confer N-acetylglucosaminyltransferase I (GlcNAc-TI) activity on Lec1 Chinese hamster ovary (CHO) cell transfectants [Kumar, R., Yang,J., Larsen,R.D. and Stanley,P. (1990) Proc. Natl. Acad Sci. USA, 87, 9948-9952] has been sequenced. The nucleotide and deduced amino acid sequences are highly homologous to previously described human and rabbit GlcNAc-TI cDNAs. A 1250 bp portion of the mouse cDNA encoding all but the first 34 amino acids of the deduced protein sequence was inducibly expressed in Escherichia coli and gave rise to a prominent fusion protein of mol. wt approximately 45 kDa whose presence correlated with high levels of GlcNAc-TI activity in cell lysates. Probes generated from the cDNA were used to show that the GlcNAc-TI gene is present in a single copy in mammals and that a homologous gene was not detectable (under low-stringency hybridization conditions) in DNA from yeast, sea urchin, Drosophila or Chaenorhaditis elegans. Genomic DNA clones that hybridized to probes generated from the GlcNAc-TI cDNA were isolated from a mouse liver library. Restriction analyses, Southern hybridization and DNA sequence analyses of subcloned genomic DNA fragments and a polymerase chain reaction (PCR) product provided evidence that the coding and 3' untranslated regions of the cDNA reside in a single exon. However, the mouse GlcNAc-TI gene (Mgat-1) includes at least one additional exon 5' of the coding region. Southern analyses of DNA from mouse-human somatic cell hybrids and in situ hybridization were used to locate the human GlcNAc-TI gene (MGAT-1) between positions q31.2 and q31.3 on chromosome 5, a region of chromosome 5 that is syntenic with a region of mouse chromosome 11. Northern analyses of adult mouse tissues revealed two GlcNAc-TI gene transcripts that are differentially expressed in different tissues.

The TCF8 gene encoding a zinc finger protein (Nil-2-a) resides on human chromosome 10p11.2.

The TCF8 gene encodes a zinc finger protein (Nil-2-a). Nil-2-a inhibits T-lymphocyte-specific interleukin 2 (IL2) gene expression by binding to a negative regulatory domain 100 nucleotides 5' of the IL2 transcription start site. Southern hybridization and somatic cell hybrids are used to demonstrate that the murine and human genomes contain related genes for Nil-2-a. TCF8 resides on human chromosome 10. Fluorescent in situ hybridization is employed to localize TCF8 to 10p11.2.

Human metallothionein genes are clustered on chromosome 16.

The metallothioneins are a family of heavy-metal binding proteins of low molecular weight. They function in the regulation of trace metal metabolism and in the protection against toxic heavy metal ions. In man, the metallothioneins are encoded by at least 10-12 genes separated into two groups, MT-I and MT-II. To understand the genomic organization of these genes and their involvement in hereditary disorders of trace metal metabolism, we have determined their chromosomal location. Using human-mouse cell hybrids and hybridization probes derived from cloned and functional human MT1 and MT2 genes, we show that the functional human genes are clustered on human chromosome 16. Analysis of RNA from somatic cell hybrids indicated that hybrids that contained human chromosome 16 expressed both human MT1 and MT2 mRNA, and this expression is regulated by both heavy metal ions and glucocorticoid hormones.

Assignment of the human phosphoserine phosphatase gene (PSP) to the pter leads to q22 region of chromosome 7.

Phosphoserine phosphatase (PSP) catalyzes the hydrolysis of phosphoserine to serine. PSP expression has been examined in human-mouse somatic cell hybrids retaining different combination of human chromosomes. Human PSP is expressed only when the pter leads to q22 segment of the human 7 and its enzyme marker beta-glucuronidase (GUSB) are retained in cell hybrids. The structural gene, PSP, is therefore assigned to this region of the human 7.