Production of a motility factor by a newly established lung adenocarcinoma cell line

We have established and characterised a cell line, designated WART, from a patient with primary adenocarcinoma of the lung. This cell line grows with a doubling time of approximately 15 hours, forms colonies in soft agarose, is tumorigenic in athymic nude mice, and has a complex karyotype with both structural and numerical abnormalities. WART serum free conditioned medium (SFCM) contains a factor which stimulates motile behavior of WART cells. This factor with an apparent molecular weight of 67 kDa induced in an autocrine fashion prominent pseudopodia, and chemotactic and chemokinetic responses. Heparin affinity chromatography, ion exchange and molecular sieve chromatography accompanied by SDS-PAGE analysis showed that the motility inducing activity was associated with a major band with molecular weight 67 kDa. The motility inducing activity of the 67 kDa protein was not sensitive to reduction with either dithiotreitol or mercaptoethanol which distinguishes it from A-2058 melanoma autocrine motility factor (AMF)/autotaxin, HT-1080 fibrosarcoma AMF and scatter factor which lose their biological activity upon reduction. This 67 kDa motility inducing factor did not augment DNA synthesis indicating that its locomotor activity is independent of mechanisms regulating cell growth. Pertusis toxin inhibited the motile response induced by the 67 kDa protein indicating a signal transduction pathway involving G proteins. Due to its production of the motility stimulating protein the cell line could facilitate studies of invasion and metastasis of human lung tumors.

Genetic heterogeneity in isogenic homozygous clonal zebrafish

The C32 isogenic homozygous diploid (IHD) strain of the zebrafish (Danio rerio) was found to be polyallelic at a malate dehydrogenase locus (sMdh-A). A variant allele is thought to have arisen via mutation within the past 10 bisexual generations that have maintained the strain since its last gynogenetic cloning event; this unique allele now predominates at the sMdh-A locus. The estimated mutation rate in this species is sufficiently high that long-term genetic homogeneity of its IHD clones cannot be assumed. Researchers using such bisexually maintained clones should be aware that they are not necessarily using genetically uniform subjects. Genetic uniformity of cloned IHD zebrafish will be maximized if experimental subjects are obtained soon after a cloning event.

Human glucose phosphate isomerase: exon mapping and gene structure

The structure of the gene for human glucose phosphate isomerase (GPI) has been determined. Three GPI clones were isolated from a human genomic library by using a full-length GPI cDNA probe and were characterized. Oligonucleotides based on the known cDNA sequence were used as primers in amplification and sequence analyses. This led to the identification of the exon-intron junctions. By this approach, 18 exons and 17 introns have been identified. The exons range in size from 44 to 431 nucleotides. The intronic sequences surrounding the exons provide useful information for the identification of mutations that give rise to human GPI deficiency associated with chronic hemolytic anemia.

Nuclear genes from the copepod Calanus finmarchicus

For biological oceanography it is important to understand the coupling between physical and biological processes in pelagic systems. The calanoid copepod Calanus finmarchicus dominates the zoo-plankton biomass and is an important link between primary producers and higher trophic levels in the northern Atlantic. Thus understanding how the physical environment affects gene expression or population genetics in this species is important. However, very few nuclear genes have been characterized from this species, making it difficult to perform these types of studies. Four cDNAs encoding actin, hexokinase, phosphoglucose isomerase, and phosphofructokinase, as well as a hexokinase genomic DNA, have been isolated and characterized. These sequences constitute important molecular tools for biological oceanographers.

Structure of the gene encoding pig phosphoglucose isomerase

Genomic clones encoding pig phosphoglucose isomerase (PGI) have been isolated and partially sequenced. The gene (Pgi) contains 18 exons, 17 introns and spans about 32 kb. This structure is partially conserved between plant and animal. A major transcription start point (tsp) has been identified 74 nucleotides (nt) upstream from the AUG. The nt sequence around the tsp is very G+C rich; a 5'-ATAAA sequence, as well as four putative Sp1-binding sites, are present. In the 3'-flanking region, an AATAAA signal has been identified. Extending from the 5'-flanking region to the first intron, a 0.6-kb CpG island has been identified. The Pgi structural gene contains several DNA repetitive elements in its non-coding regions.

cDNA cloning of the human tumor motility-stimulating protein, autotaxin, reveals a homology with phosphodiesterases

A human cDNA clone encoding autotaxin, a tumor cell motility-stimulating protein, reveals that this protein is an ecto/exo-enzyme with significant homology to the plasma cell membrane differentiation antigen PC-1. ATX is a 125-kDa glycoprotein, previously isolated from a human melanoma cell line (A2058), which elicits chemotactic and chemokinetic responses at picomolar to nanomolar concentrations. Affinity-purified antipeptide antibodies to the ATX peptide, ATX-102, were employed to screen an A2058 cDNA expression library made in lambda gt11. The partial cDNA sequence which was obtained was then extended by utilizing reverse transcriptase on total cellular RNA followed by polymerase chain reaction amplification. The isolated cDNA clone contained 3251 base pairs, and the mRNA message size was approximately 3.3 kilobases. The deduced amino acid sequence of autotaxin matched 30 previously sequenced peptides and comprised a protein of 915 amino acids. Data base analysis of the ATX sequence revealed a 45% amino acid identity (including 30 out of 33 cysteines) with PC-1, a pyrophosphatase/type I phosphodiesterase expressed on the surface of activated B cells and plasma cells. ATX, like PC-1, was found to hydrolyze the type I phosphodiesterase substrate p-nitrophenyl thymidine-5'-monophosphate. Autotaxin now defines a novel motility-regulating function for this class of ecto/exo-enzymes.

The autocrine function of vasoactive intestinal peptide on human neuroblastoma cell growth and differentiation

Direct associations between serum concentrations and immunohistochemically detectable vasoactive intestinal peptide (VIP) and maturing neuroblastoma have been documented. Furthermore, VIP has been shown to induce both the growth inhibition and morphological differentiation of cultured human neuroblastoma cell lines. As such, it is hypothesized that VIP may be operative in the autocrine regulation of neuroblastic growth and differentiation. To test this hypothesis, VIP-induced differentiation of human neuroblastoma LA-N-5 cells was performed. Significant concomitant increases in both intracellular and extracellular VIP concentrations were observed. In addition, a marked increase in VIP receptor expression was demonstrated with VIP-induced cellular differentiation. Receptor function was maintained with enhanced expression, as evidenced by an increase in the generation of intracellular cyclic adenosine monophosphate in response to exogenous VIP stimulation. Concomitant enhancement of both intracellular and extracellular VIP expression, coupled with the induction of functional specific VIP receptors during VIP-induced differentiation, provides critical evidence for the autocrine regulation of neuroblastoma maturation by this peptide.

Characterization of a novel cell line from pleomorphic adenoma of the parotid gland with myoepithelial phenotype and producing interleukin-6 as an autocrine growth factor

A cell line was obtained from a primary culture of a pleomorphic adenoma of the parotid gland in a 24-year-old woman. The cells of the line (PA 16/23) grew spontaneously in minimal culture conditions and showed stable morphologic characteristics over 30 passages. PA 16/23 cells had immunophenotypic and ultrastructural features similar to those of transformed myoepithelial cells, which are regarded as the precursors of pleomorphic adenomas. Furthermore, these cells have been demonstrated immunocytochemically to contain interleukin-6 (IL-6) on light and electron microscopic examination. IL-6 also has been found by enzyme-linked immunosorbent assay in the culture supernatant and has been proven to be capable of stimulating growth of the PA 16/23 cells.

Changes in enzyme activities in skin fibroblasts derived from persons of various ages

We examined antioxidant enzyme activities (catalase, glutathione peroxidase, and superoxide dismutase) in cultured skin fibroblasts (passage number 2-3) derived from 30 persons of various ages. With increasing ages, catalase activity decreased, glutathione peroxidase activity increased slightly, and superoxide dismutase activity was unchanged. After UVA irradiation (4.8 joule/cm2) of the fibroblasts, only catalase activity decreased by 70%. This suggests that catalase may play an important role in the aging of human skin fibroblasts.

Expression of glucose phosphate isomerase in interspecific hybrid (Mus musculus x Mus caroli) mouse embryos

Hybrid Mus musculus x Mus caroli embryos were produced by inseminating M. musculus (C57BL/OlaWs) females with M. caroli sperm. Control M. caroli embryos developed more rapidly than did control M. musculus embryos and implanted approximately 1 day earlier. At 1 1/2 days, both the hybrid embryos and those of the maternal species (M. musculus) had cleaved to the 2-cell stage. By 2 1/2 days some of the hybrids were retarded compared to M. musculus, and by 3 1/2 days most were lagging behind. This is consistent with the idea that the rate of development of hybrid embryos declines once it becomes dependent on embryo-coded gene products. We have used this difference in rate of preimplantation development, between hybrid and M. musculus embryos, to try to determine whether the activation of embryonic Gpi-1s genes, that encode glucose phosphate isomerase (GPI-1), is age-related or stage-related. In control M. musculus embryos (both mated and Al groups), the GPI-1AB and GPI-1A allozyme, indicative of paternal gene expression, were detected in 7 of 9 samples of 3 1/2-day compacted morula stage embryos and were seen in all 19 samples of 3 1/2-day blastocysts. In hybrid embryos, these allozymes were detected 1 day later. They were not detected in any 3 1/2-day samples (12 samples of compacted morulae) but were consistently detected at 4 1/2 days (4 samples of blastocysts and 2 samples of uncompacted morulae). Our interpretation of the results is that gene activation in hybrid embryos is stage-specific, rather than age-specific, and probably begins around the 8-cell stage, with detectable levels of enzyme accumulating later. Analysis of GPI-1 electrophoresis indicated that both the paternal (M. caroli) and maternal (M. musculus) Gpi-1s alleles were equally expressed in hybrid embryos and that the paternally derived allele was not activated before the maternally derived allele.

Survival of maternal mRNA in anucleate and unfertilized mouse eggs

Unfertilized mouse eggs were parthenogenetically activated in vitro and then bisected. Anucleate fragments were aged in vitro, and their protein synthesis was analyzed by two-dimensional polyacrylamide gel electrophoresis. Proteins were compared with those which were synthesized by aging unfertilized eggs and those which were translated in vitro from mRNA extracted from the unfertilized eggs. Normally cleaving parthenogenetic eggs served as controls. Cytoplasts and unfertilized eggs synthesized considerable quantities of protein after 2 days in culture. The protein patterns of cytoplasts and unfertilized eggs shifted in this time mainly within a group of proteins with a molecular mass of about 35 kDa. This shift was also seen in controls between day 1 and 2 but was delayed in unfertilized eggs. There was no clear appearance of new proteins in aging cytoplasts, which might have indicated a selective activation of maternal mRNA at a certain time after the activation stimulus, nor was such a change apparent in unfertilized eggs. The survival of maternal allozymes of glucose phosphate isomerase was tested in cytoplasts derived from fertilized eggs. The allozymes remained active during 4 days of aging and did not change their quantitative correlation.

Isolation and characterization of the phosphoglucose isomerase gene from Escherichia coli

The nucleotide sequence of the gene encoding the glycolytic enzyme phosphoglucose isomerase (PGI) from Escherichia coli is presented. The gene encodes a polypeptide of 549 amino acids. The transcriptional start point of the gene was determined and found to lie within a consensus promoter region. The amino acid sequence derived from the E. coli PGI gene can be aligned without insertions or deletions to the predicted amino acid sequence of a nuclear-encoded chloroplast isozyme of PGI from a higher plant, and the two sequences have a similarity of 87.6%. The amino acid sequence similarity between E. coli and that predicted from cDNA sequences for mouse and pig PGI is approximately 65%.

IL-6/IFN-beta-2 as a circulating hormone. Induction by cytokine administration in humans

IL-6/IFN-beta 2 is a family of phosphoglycoproteins ranging in size from 19 to 30 kDa which elicits a broad range of physiologic and immune responses. Several cytokines, including TNF, have been shown to stimulate IL-6 production in cell culture. In this report, we describe the rapid induction of circulating biologically active IL-6 by the systemic administration of rTNF to patients with cancer. Low levels of IL-6 activity could be detected in the sera of patients as early as 5 min after rTNF infusion. IL-6 levels peaked approximately 2 to 3 h after rTNF bolus administration and were undetectable in most cases within 8 h. IL-6 was detected in two separate bioassays--the hybridoma B9 proliferation and the hepatocyte-stimulating factor assay. Maximum detectable levels of IL-6 ranged from 160 to 310 hybridoma growth factor units and 11-82 ng/ml in the hepatocyte-stimulating factor assay. IL-6 induction decreased after serial, daily doses of rTNF. Serial serum samples of patients receiving IL-2 or IFN-alpha were also assayed for IL-6 production. IL-2-treated but not IFN-alpha-treated patients generated low levels of IL-6 (range less than 20 to 95 hybridoma growth factor units/ml). Interestingly, in patients treated with IL-2, serum levels of TNF were detectable and peak TNF activity preceded measurable IL-6 levels. Serum levels of acute phase plasma proteins and of corticosteroid rose in response to rTNF administration. C-reactive protein increased (2.5 to 4.0-fold) within 8 h of rTNF administration and cortisol levels rose (10- to 20-fold) within 4 h after rTNF injection. We conclude that rTNF administration in man leads to the induction of circulating IL-6 which, due to its broad range of activities, may be an important physiologic signal regulating the immune response.

Sequential expression of maternally inherited phosphoglycerate kinase-1 in the early mouse embryo

Enzyme activities of X-linked phosphoglycerate kinase (PGK-1) and autosomal glucose phosphate isomerase (GPI-1) were determined in intact mouse blastocysts and isolated inner cell masses (ICMs). Blastocysts were recovered from the uterus on day 4 of gestation and cultured overnight in vitro. ICMs were isolated by treatment with calcium ionophore A23187. On day 4, approximately 35% of the total activity of both PGK-1 and GPI-1 was located in the ICM. After overnight culture, the PGK-1 activity of the whole blastocyst nearly doubled, due to the activation of only the maternally derived gene coding for PGK-1. In the ICM, however, a pronounced decrease of PGK-1 activity was measured: only 10% of the total PGK-1 activity was measured in the ICM on day 5. In contrast to PGK-1, GPI-1 activity of the intact blastocyst remained stable from day 4 to day 5. In the ICM, the GPI-1 activity did decline, but to a lesser extent than PGK-1 activity: 20% of total GPI-1 activity was found in the ICM on day 5. These results, when compared with the data of Handyside and Hunter, suggest that the decline in GPI-1 activity in the ICM is due to a change in the ratio of trophectoderm (TE) to ICM cells. The greater reduction of PGK-1 activity in the ICM cannot, however, be explained solely by this mechanism. To explain the observed additional decrease, we postulate that Pgk-1 is not activated in the ICM prior to day 6. This implies that on day 4 maternal Pgk-1 is activated in the TE exclusively.

Glucosephosphate isomerase (GPI-1) expression in mouse ova: cis regulation of monomer realization

A survey of the glucosephosphate isomerase (GPI-1) activity expressed in mature mouse ova has revealed multiple interstrain differences. Genetic variation at a site either linked to (less than 1.1 cM) or directly associated with Gpi-1 affects the realization of GPI-1 monomers during the later stages of oocyte maturation.

A new allele of the Gpi-1t temporal gene that regulates the expression of glucose phosphate isomerase in mouse oocytes

The dimeric enzyme glucose phosphate isomerase (GPI-1) is regulated in oocytes by a cis-acting temporal gene (Gpi-1t) that maps close to the structural gene (Gpi-1s). Quantitative cellulose acetate electrophoresis of GPI-1 allozymes from unfertilized eggs produced by various Gpi-1sa / Gpi-1sb heterozygous females revealed a new Gpi-1t allele that we have designated Gpi-1tc. This allele is present in 101/H mice and a partially congenie stock that carries the Gpi-lsa gene derived from the AKR strain. We have confirmed that Gpi-1tc is closely linked to Gpi-1s and that it is cis-acting. It produces higher levels of GPI-1 in unfertilized eggs than the other two Gpi-lt alleles that are known (Gpi-1ta and Gpi-1tb) but has no effect on GPI-1 in somatic tissues or spermatozoa. This new Gpi-1t allele represents a third developmental programme for GPI-1 expression in oocytes.

Anaerobic expression of maize glucose phosphate isomerase I

Anaerobic treatment of maize seedlings results in the selective expression of 10 major and 10 minor polypeptides designated as anaerobic polypeptides (ANPs) (Sachs, M. M., Freeling, M., and Okimoto, R. (1980) Cell 20, 761-767). Enzymatic functions have been ascribed to two of these polypeptides, alcohol dehydrogenases I and II. This report identifies a third anaerobic polypeptide, a maize glucose phosphate isomerase. Glucose phosphate isomerase specific activity increased 60% in 24 h of anaerobiosis and to more than twice its original level in 72 h. Antiserum to spinach cytoplasmic glucose phosphate isomerase 1) was monospecific against maize protein, 2) reduced glucose phosphate isomerase activity in maize extracts by 60%, and 3) recognized a single polypeptide selectively labeled with [35S]methionine during anaerobiosis. This polypeptide co-purified with the major glucose phosphate isomerase of maize. Maize glucose phosphate isomerase co-migrated on two-dimensional polyacrylamide gels with ANP55, the anaerobic polypeptide with a molecular weight of 55,000 on sodium dodecyl sulfate-polyacrylamide gels. Electrophoretically distinguishable alleles of Phi 1 (phosphohexoisomerase-1 gene located at maize chromosome 1L-140) predictably altered the electrophoretic behavior of ANP55, thus proving that Phi 1 encodes ANP55 and that ANP55 is a glucose phosphate isomerase.

Induction of glycolytic enzyme synthesis in proliferating fibroblasts. Study of phosphofructokinase, glucose phosphate isomerase and pyruvate kinase

Specific activity of phosphofructokinase is 7-8-fold higher in exponentially growing human fibroblasts than in quiescent cells, but the difference is considerably less pronounced for two other glycolytic enzymes, glucose phosphate isomerase and pyruvate kinase. The ratio of the F-type to L-type phosphofructokinase subunits is essentially the same in growing and resting cells, 4:1. F-type-phosphofructokinase-related antigen concentration is decreased in resting cells as compared with proliferating fibroblasts, but relatively less than the enzyme activity; the ratio of the enzyme activity to the antigen concentration (immunological specific activity) is therefore lower in resting than in growing fibroblasts. Synthesis of phosphofructokinase, as a percentage of the total protein synthesis, is about 30-fold greater during the proliferative phase than in quiescent cells, but this difference is only 3-4-fold for glucose phosphate isomerase and pyruvate kinase. Modulation of the synthesis of phosphofructokinase therefore seems to be responsible for the changes of its specific activity in function of cell proliferation. The appearance of some inactive cross-reacting material in quiescent cells is probably due to post-translational alteration of the pre-synthesized molecules. Compared with other glycolytic enzymes, such as glucose phosphate isomerase and pyruvate kinase, phosphofructokinase seems to be the (or one of the) preferential target of glycolytic induction in proliferating cells.

Mannitol and fructose catabolic pathways of Pseudomonas aeruginosa carbohydrate-negative mutants and pleiotropic effects of certain enzyme deficiencies

Mutant strains of Pseudomonas aeruginosa PAO were isolated on the basis of their inability to utilize mannitol as sole carbon source for growth. Four linkage groups (I through IV) among these mutant strains were resolved by two-factor crosses using the general transducing phage F116, and the strains appeared to contain point mutations as evidenced by ability to give rise to spontaneous revertants with wild phenotype on mannitol minimal agar. Group I strains were affected only in ability to grow on mannitol; all were deficient in inducible mannitol dehydrogenase activity, and all but one were deficient in inducible mannitol transport activity. Fructokinase was induced in group I strains and in wild-type bacteria during growth in the presence of mannitol but not fructose, indicating the presence of a pathway specific for endogenously generated fructose. Cells grown on fructose contained phosphoenolpyruvate:fructose-1-phosphotransferase activity, and mannitol-grown cells contained a lower level of this activity. Group II mutants were deficient in constitutive phosphoglucoisomerase, failed to grow on mannitol, grew very slowly on glycerol and fructose, but grew normally on glucose and gluconate. Group III strains were deficient in both nicotinamide adenine dinucleotide- and nicotinamide adenine dinucleotide phosphate-linked glucose-6-phosphate dehydrogenase activities that reside in a single enzyme species. 6-Phosphogluconate appeared to be the inductive effector for this enzyme, which was not required for aerobic growth on glucose or gluconate. A single mannitol-negative mutant in group IV also failed to grow on glycerol and glucose, but no biochemical lesion was identified.

Evidence against gene expression after meiosis in the male mouse

Isozyme patterns in homogenates from various testicular cell types from mice were examined in an effort to ascertain whether the haploid genome is expressed during spermiogenesis. Male mice heterozygous for electrophoretic variants of several glycolytic enzymes were analyzed by starch gel electrophoresis. The enzymes examined were isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase, and glucosephosphate isomerase. The isozyme patterns produced by these dimeric enzymes reflect the relative activity of genes in each cell type. These patterns reveal the presence or absence of the transcription of specific genes during spermiogenesis. We found that the genes encoding these enzymes continue to increase during spermiogenesis. Synthesis of these enzymes most likely continues in spermatids, but this synthesis must depend upon premeiotically produced mRNA. These data provide biochemical evidence for the hypothesis that the phenotype of the haploid mammalian gamete depends upon the preceding diploid genome and that a mechanism must exist for the long term post-transcriptional regulation of gene expression during spermiogenesis.

Mannosidosis: assignment of the lysosomal alpha-mannosidase B gene to chromosome 19 in man

Human alpha-mannosidase activity (alpha-D-mannoside mannohydrolase, EC 3.2.1.24) from tissues and cultured skin fibroblasts was separated by gel electrophoresis into a neutral, cytoplasmic form (alpha-mannosidase A) and two closely related acidic, lysosomal components (alpha-mannosidase B). Human mannosidosis, an inherited glycoprotein storage disorder, has been associated with severe deficiency of both lysosomal alpha-mannosidase B molecular forms. Chromosome assignment of the gene coding for human alpha-mannosidase B (MANB) has been determined in human-mouse and human-Chinese hamster somatic cell hybrids. The human alpha-mannosidase B phenotype showed concordant segregation with the human enzyme glucosephosphate isomerase (GPI) (D-glucose-6-phosphate ketolisomerase, EC 5.3.1.9) but discordant segregation with 30 other enzyme markers representing 20 linkage groups. The glucose-phosphate isomerase gene has been assigned to chromosome 19 in man. This MANB-GPI linkage and confirming chromosome studies demonstrate assignment of the alpha-mannosidase B structural gene to chromosome 19 in man. Since mannosidosis is believed to result from a structural defect in alpha-mannosidase B, these findings suggest that the mannosidosis mutation is located on chromosome 19 in man.

Expression of alpha-D-mannosidase in man-hamster somatic cell hybrids

Two types of alpha-D-mannosidase isozymes are present in human white blood cells, human diploid fibroblasts, and HeLa cells. One of these (the S isozyme) constitutes the major alpha-D-mannosidase of the human cells, has a pH optimum of 4.4, and is associated with lysosomes. The other (the F isozyme) is most active at pH 6, is acid labile, and is located in the soluble portion of the cytoplasm. The expression of human lysosomal alpha-D-mannosidase was examined in man-hamster hybrid clones, and was found to be concordant with that of phosphohexose isomerase in 54 of 55 primary clones. A locus specifying human lysosomal alpha-D-mannosidase has therfore been assigned to chromosome 19.