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M S Nightingale

Publications and source records attributed to M S Nightingale.

At least 19 recordsLinked to original sources
PubMed1996

Interspecies relationships among ADP-ribosylation factors (ARFs): evidence of evolutionary pressure to maintain individual identities.

ADP-ribosylation factors (ARFs) are approximately 20-kDa guanine nucleotide-binding proteins that are allosteric activators of the NAD:arginine ADP-ribosyltransferase activity of cholera toxin and appear to play a role in intracellular vesicular trafficking. Although the physiological roles of these proteins have not been defined, it has been presumed that each has a specific intracellular function. To obtain genetic evidence that each ARF is under evolutionary pressure to maintain its structure, and presumably function, rat ARF cDNA clones were isolated and their nucleotide and deduced amino acid sequences were compared to those of other mammalian ARFs. Deduced amino acid sequences for rat ARFs 1, 2, 3, 5 and 6 were identical to those of the known cognate human and bovine ARFs; rat ARF4 was 96% identical to human ARF4. Nucleotide sequences of both the untranslated as well as the coding regions were highly conserved. These results indicate that the ARF proteins are, as a family, extraordinarily well conserved across mammalian species. The unusually high degree of conservation of the untranslated regions is consistent with these regions having important regulatory roles and that individual ARFs contain structurally unique elements required for specific functions.

ADP-Ribosylation Factors↗
PubMed1994

Immunological and structural conservation of mammalian skeletal muscle glycosylphosphatidylinositol-linked ADP-ribosyltransferases.

NAD:arginine ADP-ribosyltransferases catalyze the ADP-ribosylation of arginine residues in proteins. Coding region nucleic acid and deduced amino acid sequences of a human skeletal muscle ADP-ribosyltransferase cDNA were, respectively, 80.8% and 81.3% identical to those of the rabbit skeletal muscle transferase. A human transferase-specific cDNA probe detected major mRNA of 1.2 kb (mouse and rat), 3.0 kb (rabbit), 3.8 kb (monkey), and 5.7 kb (human) upon Northern analysis. Polyclonal anti-rabbit ADP-ribosyltransferase antibodies reacted with 36,000 M(r) proteins in partially purified transferase preparations from bovine, dog, and rabbit heart muscle and a 40,000 M(r) protein from human skeletal muscle. The human muscle ADP-ribosyltransferase cDNA, like the previously cloned rabbit muscle transferase, predicts predominantly hydrophobic amino- and carboxy-terminal amino acid sequences, which is characteristic of glycosylphosphatidylinositol (GPI)-anchored proteins. On immunoblots of partially purified rabbit and human skeletal muscle ADP-ribosyltransferases, anti-cross-reacting determinant antibodies detected at 36,000 and 40,000 M(r), respectively, phosphatidylinositol-specific, phospholipase C-sensitive, GPI-anchored proteins. These data are consistent with the conclusion that GPI-anchored skeletal and cardiac muscle ADP-ribosyltransferases are conserved across mammalian species.

ADP Ribose Transferases↗
PubMed1993

ARD 1, a 64-kDa guanine nucleotide-binding protein with a carboxyl-terminal ADP-ribosylation factor domain.

Clones referred to as ARD 1 were isolated from human and rat cDNA libraries. ARD 1 genes encode a putative 64-kDa protein that contains an 18-kDa ADP-ribosylation factor (ARF) domain at the carboxyl terminus and is much larger than the other monomeric approximately 20-kDa guanine nucleotide-binding ARF proteins thus far identified. ARD 1 mRNAs of 3.7 and 4.1 kilobases were detected in all rat tissues as well as in mouse and rabbit brain, human fibroblasts, and human neuroblastoma cells but not in HL-60 cells. Based on sequence identities, ARD 1 is highly conserved between rat and human. The ARF domain of ARD 1 contains the consensus sequences believed to be involved in guanine nucleotide binding, which are conserved in the ARFs and other GTP-binding proteins. Recombinant ARD 1 or the ARF domain of ARD 1, which lacks the 15 amino acids corresponding to the amino-terminal regions of ARFs stimulated, in a GTP-dependent manner, cholera toxin ADP-ribosyltransferase activity in the presence of 0.3% Tween 20. It had no effect in the presence of SDS, dimyristoylphosphatidylcholine/cholate, or cardiolipin. These observations are consistent with the conclusion that the amino-terminal region of ARF proteins is not required for activation of cholera toxin. In addition, the characteristic features of ARF proteins may be found as domains of larger mammalian proteins.

ADP-Ribosylation Factors↗
PubMed1992

Molecular characterization of NAD:arginine ADP-ribosyltransferase from rabbit skeletal muscle.

Mono-ADP-ribosylation is a reversible modification of proteins, with NAD:arginine ADP-ribosyltransferases (EC 2.4.2.31) and ADP-ribosylarginine hydrolases (EC 3.2.2.19) catalyzing the opposing reactions in an ADP-ribosylation cycle. A membrane-associated arginine-specific (mono)-ADP-ribosyltransferase was purified 215,000-fold from rabbit skeletal muscle. On the basis of the amino acid sequences of HPLC-purified tryptic peptides, degenerate oligonucleotide primers were synthesized and used in a polymerase chain reaction (PCR)-based procedure to generate cDNA. A specific probe, based on PCR-generated sequence, was used to screen a rabbit skeletal muscle cDNA library. A composite cDNA sequence, obtained from library screening and rapid amplification of the 5' end of the cDNA, contained a 981-base-pair open reading frame, encoding a 36,134-Da protein. The deduced amino acid sequence contained the sequences of the tryptic peptides, hydrophobic amino and carboxyl termini, and two potential sites for N-linked glycosylation. Escherichia coli cells transformed with an expression vector containing transferase-specific sequence expressed ADP-ribosyltransferase activity. A transferase-specific oligonucleotide probe recognized a 4-kilobase mRNA expressed primarily in rabbit skeletal and cardiac muscle. There was no extended similarity in deduced amino acid sequences of the muscle transferase and several bacterial ADP-ribosylating toxins. The hydrophobic amino and carboxyl termini may represent a signal peptide and a site for a glycosyl-phosphatidylinositol anchor, respectively.

ADP Ribose Transferases↗
PubMed1992

Regulation of ADP-ribosylation factor (ARF) expression. Cross-species conservation of the developmental and tissue-specific alternative polyadenylation of ARF 4 mRNA.

ADP-ribosylation factors (ARFs), approximately 20-kDa guanine nucleotide-binding proteins, are involved in protein trafficking and enhance cholera toxin ADP-ribosyltransferase activity. Expression of six ARF genes was examined in mammalian tissues; only ARF 4 mRNA was detected in rat testis in forms considerably shorter than those in other tissues. Testis-specific expression of short forms of ARF 4 mRNA was observed in several mammalian species. On Northern analysis of the developmental expression of rat ARF 4 mRNA, appearance of the shorter species was consistent with its involvement in a late stage of spermatogenesis. Sequences of products of rapid amplification of cDNA ends (RACE-polymerase chain reaction) of rat ARF 4 mRNA revealed that different mRNAs resulted from the use of three polyadenylation signals, one AUUAAA and two AAUAAA. Sequences of 3'-untranslated regions of rat and human ARF 4 mRNA were very similar with identical polyadenylation signals at similar positions. Of the ARF 4 mRNAs identified by RACE-PCR, with sizes of 1.1, 1.3, and 1.8 kb, the 1.1-kb mRNA was predominant in adult testis. By in situ hybridization, the 1.1-kb mRNA was identified primarily in mature sperm, consistent with the developmental studies. Shorter mRNAs, thought to be more stable, may compensate for cessation of transcription at late stages of spermatogenesis.

ADP-Ribosylation Factors↗
PubMed1992

Molecular and immunological characterization of ADP-ribosylarginine hydrolases.

Mono-ADP-ribosylation is a reversible modification of proteins with NAD:arginine ADP-ribosyltransferases and ADP-ribosylarginine hydrolases catalyzing the forward and reverse reactions, respectively. Hydrolase activities were present in a variety of animal species, with the highest specific activities found in rat and mouse brain, spleen, and testis. Rat and mouse hydrolases were dithiothreitol- and Mg(2+)-dependent, whereas the bovine and guinea pig enzymes were dithiothreitol-independent. A rat brain hydrolase was purified approximately 20,000-fold and represented the major approximately 39-kDa protein on denaturing gels. Immunoaffinity-purified rabbit polyclonal antibodies reacted with 39-kDa proteins from turkey erythrocytes and rat, mouse, and calf brains. A rat brain cDNA library was screened using oligonucleotide and polymerase chain reaction-generated cDNA probes. Inserts from two overlapping clones yielded a composite sequence that included a 1086-base pair open reading frame, which contained amino acid sequences found in the purified hydrolase. A hydrolase fusion protein, synthesized in Escherichia coli, reacted with anti-39-kDa polyclonal antibodies and exhibited Mg(2+)- and dithiothreitol-dependent hydrolase activity. A coding region cDNA hybridized readily to a 1.7-kilobase band in rat and mouse poly(A)+ RNA, but poorly to bovine, chicken, rabbit, and human poly(A)+ RNA. The immunological and molecular biological data are consistent with partial conservation of hydrolase structure across animal species.

Amino Acid Sequence↗
PubMed1992

Conservation of a 23-kDa human transplantation antigen in mammalian species.

A group of transplantation antigens, referred to as tum- antigens, were identified in mouse tumor cells that had been mutagenized to produce variant cells and were recognized by clonal cytolytic T lymphocytes (CTL). Alterations in these variant cells that were recognized by CTL resulted from point mutations in the genes of specific proteins. We have isolated human and bovine cDNA clones that encode the homologs of the mouse tum- antigen P198. This 23.6-kDa protein is highly basic with a predicted pI of 11.55. p23/P198 is highly conserved across mammalian species, with > 94% identity (97% including conservative substitutions) among the human, bovine, and mouse deduced amino acid sequences. The nucleotide sequences of both the coding and 5'- and 3'-untranslated regions from human, bovine, and mouse are also highly conserved with > 88% identity in the coding regions. Hybridization of poly(A)+ RNA from various mammalian sources with cDNA and oligonucleotides specific for the coding region identified two mRNAs of 1.2 and 0.8 kb, whereas probes specific for the 3'-untranslated region between two consensus polyadenylation signals hybridized with the 1.2-kb, but not the 0.8-kb, mRNA. The abundance of the 1.2-kb mRNA relative to that of the 0.8-kb species varied depending upon the cell type. A single predominant transcription initiation site was mapped by primer extension. These studies indicate that this highly basic 23.6-kDa protein is encoded by two major mRNA species that differ only in the length of their 3'-untranslated regions and that the mechanism that gives rise to these two mRNAs, utilization of alternative polyadenylation sites, is conserved across species.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1989

Tissue and species distribution of mRNA encoding two ADP-ribosylation factors, 20-kDa guanine nucleotide binding proteins.

Cholera toxin catalyzed ADP-ribosylation of Gs alpha, the stimulatory guanine nucleotide binding protein of the adenylyl cyclase system, is enhanced by approximately 20-kDa guanine nucleotide binding proteins, termed ADP-ribosylation factors or ARFs. ARF is an allosteric activator of the A1 catalytic protein of the toxin. Bovine ARF cDNA clones, ARF-1 isolated from adrenal (Sewell & Kahn, 1988) and ARF-2B from retina (Price et al., 1988), exhibit nucleotide and deduced amino acid sequences that are 80% and 96% identical, respectively, in the coding region. To determine tissue and species distribution of ARF-like mRNAs, bovine ARF-2B and human ARF-1 cDNAs and 30- or 48-base oligonucleotide probes that distinguish between ARF-1 and ARF-2B cDNAs in coding and 3'-untranslated regions were used for Northern analysis of poly(A+) RNA from different tissues and species. On the basis of hybridization with specific oligonucleotide probes, all bovine tissues contained mRNAs of 1.7 and 2.1 kb that were related to ARF-1 and ARF-2B, respectively. Northern analysis of brain poly(A+) RNA from different species with ARF-2B and ARF-1 cDNAs at low stringency demonstrated several bands varying in size from 0.9 to 3.7 kb. A 1.7-kb band consistently hybridized with an ARF-1 30-base coding-region probe but not with a probe for the 3'-untranslated region. Similar ARF-2B oligonucleotide probes did not hybridize with rat, mouse, rabbit, or human brain mRNA. Cleavage of ARF-2B cDNA with PvuII generated two fragments, one containing coding and the other 3'-noncoding region.(ABSTRACT TRUNCATED AT 250 WORDS)

ADP-Ribosylation Factors↗
PubMed1989

Molecular cloning, characterization, and expression of human ADP-ribosylation factors: two guanine nucleotide-dependent activators of cholera toxin.

ADP-ribosylation factors (ARFs) are small guanine nucleotide-binding proteins that enhance the enzymatic activities of cholera toxin. Two ARF cDNAs, ARF1 and ARF3, were cloned from a human cerebellum library. Based on deduced amino acid sequences and patterns of hybridization of cDNA and oligonucleotide probes with mammalian brain poly(A)+ RNA, human ARF1 is the homologue of bovine ARF1. Human ARF3, which differs from bovine ARF1 and bovine ARF2, appears to represent a newly identified third type of ARF. Hybridization patterns of human ARF cDNA and clone-specific oligonucleotides with poly(A)+ RNA are consistent with the presence of at least two, and perhaps four, separate ARF messages in human brain. In vitro translation of ARF1, ARF2, and ARF3 produced proteins that behaved, by SDS/PAGE, similar to a purified soluble brain ARF. Deduced amino acid sequences of human ARF1 and ARF3 contain regions, similar to those in other G proteins, that are believed to be involved in GTP binding and hydrolysis. ARFs also exhibit a modest degree of homology with a bovine phospholipase C. The observations reported here support the conclusion that the ARFs are members of a multigene family of small guanine nucleotide-binding proteins. Definition of the regulation of ARF mRNAs and of function(s) of recombinant ARF proteins will aid in the elucidation of the physiologic role(s) of ARFs.

ADP-Ribosylation Factors↗
PubMed1988

Characterization of a cDNA clone encoding the calmodulin-binding domain of mouse brain calcineurin.

A cDNA clone corresponding to a portion of the catalytic subunit of calmodulin (CaM)-dependent phosphoprotein phosphatase (calcineurin) was isolated from a murine brain library by expression vector immunoscreening. A beta-galactosidase fusion protein that reacted on Western blots with anti-calcineurin antibodies and biotinylated CaM was purified in preparative amounts using CaM-Sepharose affinity chromatography. Partial digestion of the hybrid protein with Staphylococcus aureus V-8 protease produced several immunoreactive peptides that appeared identical to fragments generated from authentic brain calcineurin. The 1111-base-pair (bp) EcoRI insert contained an open reading frame encoding a protein of 35 kDa followed by a 190-bp 3' noncoding region; seven peptides obtained by partial amino acid sequencing of the bovine brain enzyme were found in the deduced sequence. A domain approximately 12 kDa from the carboxyl terminus was deduced to be the CaM-binding site based on consensus structural features and a sequence of seven amino acids highly related to smooth muscle myosin light-chain kinase. Two regions with identity to protein phosphatases 1 and 2A were found in the amino half of the cloned sequence; however, the intervening sequence contained apparent insertions, suggesting splicing of subdomains. Thus, the structure of calcineurin is chimeric, consisting of conserved catalytic elements and a regulatory CaM-binding domain.

Amino Acid Sequence↗
PubMed1988

A rapid non-radioactive procedure for plaque hybridization using biotinylated probes prepared by random primed labeling.

A simple, non-radioactive method has been developed for the rapid screening of phage libraries. In the present study, nanogram amounts of a small restriction fragment (135 bp) were biotinylated via random primed labeling and used to probe cDNA libraries using a modified plaque hybridization protocol. The high backgrounds that are seen typically with avidin/biotin-based methods for plaque hybridization were eliminated by incubation of filters with one of several different proteases prior to hybridization. A comparison of several detection systems indicated that streptavidin conjugated to calf intestinal alkaline phosphatase (AP) was the most sensitive, yielding signals comparable to those obtained with 32P-labeled probes. The times required for phage growth and pre-hybridization were reduced substantially, permitting a convenient one-day screening protocol. Nitrocellulose filters gave the best signal to noise ratio, although "streaking" of plaque DNA was observed occasionally; this problem can be overcome by using nylon-based membranes, which allows exact visualization of the positive plaques. The method was highly reliable; 29 out of 33 putative clones retested positive and the authenticity of these was confirmed by DNA sequence analysis. The random primed biotinylation procedure has been utilized successfully with several different cDNA fragments and has proven useful for other hybridization-based methods (Northern and Southern blots), without the problems associated with the use of radiolabeled probes.

Blotting, Northern↗
PubMed1983

Effects of toxic substances on female reproduction.

Successful reproduction requires a complex series of interdependent physiological, cellular and molecular events. In the female many of these interdependent events are vulnerable to interruption by xenobiotic compounds. The physiological steps in the female reproductive cycle are reviewed. Selected xenobiotics which interrupt this cycle are presented and their mechanisms and site of adverse effects are discussed. Finally, a more detailed discussion of chemically induced ovarian failure in the human and an experimental animal model system is presented.

Animals↗
PubMed1983

Oocyte destruction by polycyclic aromatic hydrocarbons.

Certain polycyclic aromatic hydrocarbons, ubiquitous environmental pollutants, destroy oocytes. Oocyte destruction by polycyclic hydrocarbons requires distribution of the parent hydrocarbon to the ovary where ovarian enzymes metabolize the compound to reactive intermediates responsible for ovotoxicity. Descriptive assays of polycyclic hydrocarbon metabolic activation such as the aryl hydrocarbon (benzo(a)pyrene) hydroxylase assay (AHH) are not good predictors of strain or species differences in sensitivity to polycyclic hydrocarbon ovotoxicity. Using benzo(a)pyrene as a probe of ovarian metabolic processing suggests that the rate of formation of metabolites along the metabolic pathway to the 7,8-dihydrodiol-9,10-epoxide may be the appropriate measure of the role of metabolic activation in strain or species differences in sensitivity to oocyte destruction. The multistep metabolic pathway involved in ovarian metabolic processing of benzo(a)pyrene may represent a useful model for exploring the roles of metabolic activation, detoxification, intrinsic sensitivity, and repair in reproductive toxicity.

Animals↗
PubMed1982

Oocyte destruction by polycyclic aromatic hydrocarbons is not linked to the inducibility of ovarian aryl hydrocarbon (benzo(a)pyrene) hydroxylase activity in (DBA/2N X C57BL/6N) F1 X DBA/2N backcross mice.

The role of the Ah locus and ovarian aryl hydrocarbon (benzo(a)pyrene) hydroxylase activity (AHH, EC 1.14.14.1) in ovotoxicity produced by the polycyclic aromatic hydrocarbons benzo(a)pyrene (BP), 3-methylcholanthrene (3-MC), and 7,12-dimethylbenz(a)anthracene (DMBA) was explored in Ah-responsive and Ah-nonresponsive (DBA/2N X C57BL/6N) F1 X DBA/2N backcross (F1 X D2) mice. The F1 X D2 backcross mice were phenotyped by zoxazolamine muscle paralysis time and separated into responsive and nonresponsive groups. Basal ovarian AHH activity was similar in both responsive and nonresponsive phenotypes (0.2 fluorescence units/mg/30 minutes). After treatment with one of the three polycyclic hydrocarbons (100 mg/kg, IP), ovarian AHH activity was induced only in the responsive F1 X D2 phenotype (0.4 fluorescence units/mg/30 minutes), demonstrating that inducibility of ovarian AHH activity is associated with the Ahb allele. Although responsive and nonresponsive backcross mice difference in inducibility of ovarian AHH activity, no difference was observed in the rate of, or sensitivity to, primordial oocyte destruction by the three tested polycyclic hydrocarbons. At 15 days after treatment with a single injection of BP (100 mg/kg, IP), approximately 30% of the primordial oocytes were destroyed in both responsive and nonresponsive F1 X D2 mice. The time course for oocyte destruction over the 15-day observation period was similar in both phenotypes. DMBA (100 mg/kg, IP) destroyed all of the primordial oocytes between 9 and 12 days after treatment with similar time courses in both responsive and nonresponsive phenotypes. Treatment with 3-MC (100 mg/kg, IP) destroyed approximately 40% and 70% of the primordial oocytes in responsive and nonresponsive F1 X D2 mice, respectively. Although ovarian metabolism of polycyclic hydrocarbons is necessary for ovotoxicity, oocyte destruction is not linked to the Ah locus. Sensitivity to, or the time course of, ovotoxicity by polycyclic aromatic hydrocarbons most likely reflects the biological sum of the processes of metabolic activation, detoxication, and repair and cannot be simply represented by a single enzymatic assay such as ovarian AHH activity.

Animals↗