Xenopus fibrinogen synthesis and secretion. Analysis of precursor polypeptides and their post-translational modification.

Xenopus fibrinogen is distinct from that of mammals in that the B beta subunit of the secreted protein has a higher apparent molecular weight than either the A alpha or the gamma subunit. A precursor polypeptide for each subunit was identified among the products translated in vitro from liver mRNA. Pre-A alpha is larger than pre-B beta and pre-gamma is the smallest of the three.

Transcriptional and genetic analyses of the herpes simplex virus type 1 genome: coordinates 0.29 to 0.45.

We have constructed a map of the genes encoded by a 23,000-nucleotide-pair region of herpes simplex virus type 1. This region, defined by the three adjacent EcoRI fragments N (map coordinates 0.298 to 0.

Expression of herpes simplex virus beta and gamma genes integrated in mammalian cells and their induction by an alpha gene product.

The proteins of herpes simplex virus type 1 (HSV-1) form three kinetic groups termed alpha, beta, and gamma, whose synthesis is regulated in a cascade fashion. alpha products are synthesized first during infection, and they are required for synthesis of beta and gamma proteins. To examine the expression of several HSV-1 beta and gamma genes in the absence of alpha functions, we transferred into mammalian cells a plasmid containing a region of the HSV-1 genome that codes for only beta and gamma genes (0.

The pH within the jelly coat of sea urchin eggs.

Because low molecular weight factors isolated from sea urchin egg jelly increase sperm motility and respiration, but only at a pH less than 7.4, H. Ohtake (J.

Efficient recovery of functionally intact mRNA from agarose gels via transfer to an ion-exchange membrane.

A simple method is described for the efficient recovery of intact mRNA from high resolution agarose gels. Fractionation of RNA is accomplished by gel electrophoresis under denaturing conditions using methylmercuric hydroxide. The RNA in the gel is then transferred electrophoretically to a diethylaminoethyl (DEAE)-membrane.

Physical mapping of the mutation in an antigenic variant of herpes simplex virus type 1 by use of an immunoreactive plaque assay.

Two mutations affecting herpes simplex virus type 1 glycoprotein B were mapped by marker rescue using cloned sequences of wild-type herpes simplex virus type 1 strain KOS DNA. One mutant, tsB5, is a temperature-sensitive mutant which does not express mature, functional glycoprotein B at the nonpermissive temperature. The other mutant, marB1.

Xenopus fibrinogen. Characterization of subunits and hormonal regulation of biosynthesis.

In this paper we describe the purification and characterization of Xenopus plasma fibrinogen and the hormonal factors which regulate synthesis and secretion of fibrinogen in liver parenchymal cells in primary culture. As in other vertebrate species, Xenopus fibrinogen is composed of three nonidentical polypeptide chains, A alpha, B beta, and gamma. In contrast to mammalian fibrinogens, the B beta chain of Xenopus fibrinogen has a higher apparent molecular weight than the A alpha chain.

Role of anchorage in the expression of tumorigenicity of untransformed mouse cell lines.

Cultured mouse cells were tested for tumorigenicity in nude mice with both a conventional assay (injection of cell suspensions) and a new test involving implantation of cells grown on gelatin sponges. Sublines of Balb/3T3 cells, obtained from different sources, varied in their tumorigenic potential with either assay. One subline (A) formed distinctive precancerous nodules only in the sponge assay; these nodules often became progressive after a latent period of 3-4 months.

Waterfowl mortality caused by aflatoxicosis in Texas.

Waterfowl mortality caused by aflatoxicosis occurred in two separate areas in Texas during the 1977-78 wintering season. The first outbreak occurred in snow geese (Anser caerulescens) on the Gulf Coast prairies, followed by an outbreak in mallards (Anas platyrhynchos) in the north-central portion of the state. Aflatoxin B1 levels in geese were 500 ng/g (dry weight).

Studies of the mechanism of the electrical polyspermy block using voltage clamp during cross-species fertilization.

Prevention of polyspermic fertilization in sea urchins (Jaffe, 1976, Nature (Lond.). 261:68-71) and the worm Urechis (Gould-Somero, Jaffe, and Holland, 1979, J.

The effect of application frequency on epidermal carcinogenesis assays.

Classic mouse skin-painting assays of such highly-complex mixtures as petroleums and synthetic fuels may lead to severe local cytotoxic effects that can alter tumorigenesis. This effect can be particularly disruptive in dose-response studies where a wide range of doses is employed. The experiments described here illustrate that frequency of exposure may be more important than the concentration of individual doses.

The work of the psychiatrist in a rehabilitation hospital.

Over an 18 month period, 49 patients in a physical rehabilitation hospital were referred to an attached psychiatrist. Formal psychiatric disorder was uncommon, and the mood changes and behaviour disturbances observed often resulted from a poor adjustment to recent physical disability by patients or their families. The most important role of the psychiatrist in management was in helping rehabilitation staff use their own skills to deal effectively with the inevitable emotional disturbances which occur in this setting.

Modulation of transcription from chromatin assembled in vitro.

A small plasmid DNA was assembled into chromatin in vitro by incubation in an extract prepared frog eggs of Xenopus laevis. The plasmid DNA contrained the regulatory region of the Escherichia coli lac operon, the transcription of which is under positive regulation by catabolite activator protein (CAP) and negative regulation by lac repressor. After incubation in the egg extract the plasmid DNA acquired approximately 60% of the predicted maximum number of nucleosomes.

Characterization of herpes simplex virus type 1 RNA present in the absence of de novo protein synthesis.

We used herpes simplex virus type 1 (HSV-1) DNA and restriction fragments of HSV-1 DNA covalently coupled to cellulose as a reagent to isolate for further characterization the major and minor HSV-1 immediate-early mRNA species in HeLa cells infected and maintained in the absence of de novo protein synthesis. Five major and several minor immediate-early mRNA species were characterized. One major species was a 4.

The effects of positive end-expiratory pressure on right and left ventricular performance.

The cardiovascular effects of positive end-expiratory pressure (PEEP) were studied in mechanically ventilated, vagotomized, Beta-blocked, anesthetized dogs. To compensate for the effect of PEEP on decreasing systemic venous return, acute plasma volume expansion was accomplished returning stroke volume and cardiac output to control values. Left and right ventricular filling pressures (LVFP and RVFP) and aortic pressure were measured relative to pressure (transmural pressure).

Isolation and translation of mRNA encoded by a specific region of the herpes simplex virus type 1 genome.

We have examined in detail the major mRNA species encoded by the region of the herpes simplex virus type 1 genome encoded by HindIII fragment K (0.53-0.59 from the left end of the prototype arrangement of the genome) by using this restriction fragment bound to cellulose as a reagent for isolation of this mRNA.

Isolation and localization of herpes simplex virus type 1 mRNA abundant before viral DNA synthesis.

Herpes simplex virus type 1 (HSV-1) DNA covalently bound to cellulose was used as a reagent to isolate viral RNA transcripts for size analysis on denaturing agarose gels. Nuclear and polyribosomal RNA isolated at 2 h postinfection (p.i.

Electrically mediated fast polyspermy block in eggs of the marine worm, Urechis caupo.

Previous work has established that the polyspermy block in Urechis acts at the level of sperm-egg membrane fusion. (J. Exp.

Isolation and localization of herpes simplex virus type 1 mRNA.

Herpes simplex virus (HSV) DNA bound to cellulose has been used as a reagent to isolate viral mRNA for size analysis on denaturing agarose gels. Total viral polysomal polyadenylated RNA was isolated from cells late after infection when such RNA has sequences encoded by approximately 45% of the HSV DNA. This RNA has a size range of from 1.