Monoclonal antibody Tor 23 binds a subset of neural cells in the human cortex and displays an altered binding distribution in Alzheimer's disease.

Recent evidence suggests that alterations in molecules of the external neuronal surface may be pivotal factors in Alzheimer's disease (AD) either as primary or secondary lesions. We are studying neuronal surface components with a library of monoclonal antibodies (MAbs) made to highly purified, exclusively cholinergic nerve terminals of the Torpedo ray. The most extensively characterized of the Tor MAbs.

Secretion of the major progesterone-induced proteins of the sheep uterus by caruncular and intercaruncular endometrium of the pregnant ewe from days 20-140 of gestation.

An experiment was performed to evaluate the types and quantity of proteins secreted by intercaruncular endometrium at days 20, 60, 100 and 140 of gestation and caruncular endometrium from days 100 and 140 of gestation. Tissues were obtained from ewes made unilaterally pregnant. Based on SDS polyacrylamide gel electrophoresis (SDS-PAGE), the major proteins present in uterine fluid at days 60-140 of gestation were the uterine milk proteins (UTM-proteins), a pair of structurally-related, progesterone-induced polypeptides with molecular weights of 55,000 and 57,000.

Comparison of the physical and recombination maps of the mouse X chromosome.

The locations of five random mouse genomic DNA markers and five cloned genes, including the genes for clotting factors VIII and IX (Cf-8 and Cf-9), Duchenne muscular dystrophy (Dmd), phosphoglycerate kinase-1 (Pgk-1), and alpha-galactosidase (Ags), on the mouse X chromosome were determined by in situ hybridization. The five random DNA markers provide new genetic loci with useful restriction fragment length polymorphisms between mouse strains and species, including one locus close to the centromeric region of the mouse X chromosome. The physical map and the recombination map of these loci on the X chromosome were compared.

Contractile activation and the effects of 2,3-butanedione monoxime (BDM) in skinned cardiac preparations from normal and dystrophic mice (129/ReJ).

Small cardiac myofibrillar preparations were obtained from the right ventricle of normal (129/ReJ) and dystrophic (129/ReJ dy/dy) mice and were chemically skinned in a relaxing solution by exposure to Triton X-100 (3% v/v). (2) The isometric force produced in these skinned cardiac preparations at different sarcomere lengths was measured in solutions of different [Ca2+] and ionic strength. The effect of the negative inotropic drug 2,3-butanedione monoxime (BDM), which is known to act at the myofibrillar level was also investigated.

Dissociation of force from myofibrillar MgATPase and stiffness at short sarcomere lengths in rat and toad skeletal muscle.

1. Single fast-twitch fibres from the extensor digitorum longus muscle of the rat, Rattus norvegicus, and single twitch fibres from the iliofibularis muscle of the cane toad, Bufo marinus, were mechanically skinned and then used to measure maximally Ca2+-activated [( Ca2+] greater than 0.03 mmol l-1) isometric force production, myofibrillar MgATPase activity and fibre stiffness at different sarcomere lengths.

Presence of the major progesterone-induced proteins of the sheep endometrium in fetal fluids.

Allantoic and amniotic fluids were collected on Days 60 (n = 3), 100 (n = 4), and 140 (n = 3) of pregnancy. The presence of uterine milk proteins (UTM-proteins) in these samples was evaluated by Ouchterlony immunodiffusion and enzyme-linked immunoabsorbant assay (ELISA). Eight of ten samples of allantoic fluid and three of ten samples of amniotic fluid produced one or two immunoprecipitin bands against antiserum to UTM-proteins.

Modification of immune function during pregnancy by products of the sheep uterus and conceptus.

The preimplantation sheep conceptus produces several molecules that inhibit lymphocyte responses in vitro to mitogens or allogeneic cells, including prostaglandin E-2 and a lactosaminoglycan-containing glycoprotein of Mr 800,000-900,000. Additionally, the definitive placenta releases immunosuppressive factors when placed in culture. One of these is a heat- and protease-stable, carbohydrate-containing molecule released by explants of cultured fetal cotyledons.

Effects of 2,3-butanedione monoxime on the contractile activation properties of fast- and slow-twitch rat muscle fibres.

1. The effects of 2,3-butanedione monoxime (BDM, 0.2-10 mmol/l) have been examined at different temperatures on calcium transients (measured with aequorin) and isometric force in intact bundles of fibres from soleus (slow-twitch) and extensor digitorum longus (EDL; fast-twitch) muscles of the rat and on Ca2+-activated isometric force of mechanically skinned soleus and EDL fibres.

Multilocus molecular mapping of the mouse X chromosome.

Using restriction fragment length polymorphisms (RFLPs) and enzymatic variants between distantly related mouse species, we have assigned three genes to the mouse X chromosome and concurrently mapped a total of eight genes spanning an estimated 50 cM of the chromosome. Segregation of RFLPs in over 200 male progeny from interspecies backcrosses between the inbred strain C57BL/6JRos and either wild-derived Mus musculus or Mus spretus was followed for the murine genes Timp (tissue inhibitor of metalloproteinases), Cf-8 (coagulation factor VIII), and Rsvp (red-sensitive visual pigment) and the known X-linked markers Otc, Hprt, Cf-9, G6pd, and Ags. From the centromere, the gene order was defined as Otc, Timp, Hprt, Cf-9, (Cf-8/Rsvp/G6pd), Ags, by minimizing the number of multiple recombinational events.

The proto-oncogene c-kit encoding a transmembrane tyrosine kinase receptor maps to the mouse W locus.

Mice carrying mutations at the W locus located on chromosome 5 are characterized by severe macrocytic anaemia, lack of hair pigmentation and sterility. Mutations at this locus appear to affect the proliferation and/or migration of cells during early embryogenesis and result in an intrinsic defect in the haematopoietic stem cell hierarchy. An understanding of the molecular basis of the complex and pleiotropic phenotype in W mutant mice would thus provide insights into the important developmental processes of gametogenesis, melanogenesis and haematopoiesis.

An atlas of a rare neuronal surface antigen in the rat central nervous system.

The mature nervous system contains functional synaptic networks composed of neuronal sets and subsets whose identity and maintenance may rely on external surface molecules specific for these neuronal subdivisions. Such molecules may reside permanently on specific neurons, serving to identify those neurons within a complex population. From a collection of monoclonal antibodies made to the Torpedo cholinergic synaptosome preparation, we have identified several antibodies that bind the surface of some, but not all, neurons of the mature rat brain (Kushner and Stephenson, 1983; Kushner, 1984).

Golden: a novel coat color mutant in the wild mouse Mus caroli.

We identified a spontaneous pigmentation mutant in the wild mouse species Mus caroli. Mutant mice exhibit a golden coat color on the agouti background, easily distinguishable from the darker wild type. The golden phenotype segregates as an autosomal recessive, showing no linkage to the sex-linked enzyme marker glucose-6-phosphate dehydrogenase.

Torpedo monoclonal antibodies react with components of the human peripheral nervous system.

A panel of 141 monoclonal antibodies, generated to the Torpedo ray cholinergic nerve terminal preparation, were tested for binding to components of human nerve and muscle. Tested by immunofluorescence, 13 of the antibodies reacted with components of the human intercostal nerve, and 9 bound either muscle or blood vessels in a diversity of staining patterns. Results indicate that the antibodies identify a spectrum of different antigens.

Effects of X-irradiation at different times during development on the yield of somatic mutations in melanocytes of the mouse.

The effect of 2.0 Gy X-irradiation at different times during foetal and early post-natal development on the resultant somatic mutation frequency was investigated by scoring for changes in follicular melanocyte morphology (nucleofugal vs. nucleopetal) in mice heterozygous for the recessive coat colour mutations dilute (d) and leaden (ln).

Regional localization of the murine Duchenne muscular dystrophy gene on the mouse X chromosome.

The murine locus corresponding to the human Duchenne/Becker muscular dystrophy (DMD) gene has been regionally mapped on the mouse X chromosome by hybridizing DNA from interspecies mouse crosses with a cDNA clone for the mouse Dmd gene. The results demonstrate that the relative organization of genes on the murine and human X chromosomes is more divergent than has previously been postulated. Furthermore, the mouse Dmd gene maps to a similar region of the X chromosome as does the mouse muscular dystrophy mutation mdx, providing further evidence that the mdx mutant may be a murine equivalent of human DMD.

Ca2+-movements in muscle modulated by the state of K+-channels in the sarcoplasmic reticulum membranes.

1. A procedure has been developed to load Ca2+ reversibly by the sarcoplasmic reticulum (SR) of mechanically skinned muscle fibres from the toad Bufo marinus under controlled conditions and was employed to investigate the effects of conditions known to reduce the K+ conductance located in the SR-membrane during Ca2+-loading on the amount of Ca2+ releasable by caffeine. 2.

Monoclonal antibody Tor 23 recognizes a determinant of a presynaptic acetylcholinesterase.

A significant proportion of the acetylcholinesterase that is present in the electric organ of Torpedo californica exists as a presynaptic membrane molecule. The monoclonal antibody Tor 23 binds the Torpedo presynaptic nerve membrane where it recognizes a polypeptide of 68,000 daltons. Our present studies indicate that Tor 23 identifies acetylcholinesterase.

Thermal dependence of maximum Ca2+-activated force in skinned muscle fibres of the toad Bufo marinus acclimated at different temperatures.

Mechanically skinned muscle fibres from the twitch region of the iliofibularis muscle of cool- (16 +/- 1 degree C) and warm- (32 +/- 1 degree C) acclimated cane toads (Bufo marinus) were activated maximally by Ca2+ in solutions of different pH and at different temperatures (approx. 1-35 degrees C). Acclimation of up to 12 weeks at 16 degrees C and up to 8 weeks at 32 degrees C did not modify the marked thermal dependence of isometric force in the skeletal muscle fibres of the cane toad.

Investigation of the potential for mitotic recombination in the mouse.

A variation of the mouse spot test is described that is designed to distinguish between spots of altered coat colour that arise by reciprocal mitotic recombination and those caused by somatic mutation or non-disjunction. Mouse fetuses that were heterozygous for two, linked coat colour genes were irradiated (1.5 Gy X-rays) in utero at 10.

Activation of the contractile apparatus of skinned fibres of frog by the divalent cations barium, cadmium and nickel.

The contractile apparatus of mechanically skinned muscle fibres of frog can be reversibly activated by Ba2+ and Cd2+. The maximum force induced by both Ba2+ and Cd2+ is the same as that induced by Ca2+ and Sr2+. The ionic concentrations of the divalent cations required to induce 50% of the maximum activated force at 1 mM-Mg2+, pH 7.