SUMMARYFour monoclonal antibodies to glycoprotein D (gD) of herpes simplex virus (HSV) types 1 and 2 neutralized virus in the presence of complement but exhibited diverse activities in its absence. Amino acid substitutions that conferred resistance to neutralization by each antibody were identified by deriving the nucleotide sequence of the gD gene from resistant mutants. Each antibody selected a substitution from different parts of the molecule and mutants resistant to a single antibody always arose from the same mutation. One of the antibodies reacted with a synthetic oligopeptide corresponding to the region of the molecule in which amino acid substitution conferred resistance, but the remaining three antibodies failed to react with predicted oligopeptide targets. These antibodies may therefore react with 'discontinuous' epitopes, a view supported by the observation that two of these three antibodies competed with each other in binding assays despite the fact that substitutions conferring resistance to neutralization arose nearly 100 residues apart in the primary sequence. The four antibodies had very different biological properties. One antibody neutralized infectivity but did not inhibit cell fusion, one antibody inhibited cell fusion but did not neutralize, while a third antibody had both activities. One antibody had neither activity but enhanced the infectivity of HSV-2 in a type-specific manner. The ability of antibodies to inhibit cell fusion by syncytial virus strains correlated with an ability to prevent plaque enlargement by a non-syncytial virus strain, implying a role for gD in the intercellular spread of virus that is independent of the syncytial phenotype. We found no correlation between neutralizing activity and anti-fusion activity suggesting that, while gD is involved in cell fusion, it has at least one other function which is required for infectivity.

We aimed to identify novel molecular mechanisms for muscle growth during administration of anabolic agents. Growing pigs (Duroc/(Landrace/Large-White)) were administered Ractopamine (a beta-adrenergic agonist; BA; 20 ppm in feed) or Reporcin (recombinant growth hormone; GH; 10 mg/48 hours injected) and compared to a control cohort (feed only; no injections) over a 27-day time course (1, 3, 7, 13 or 27-days). Longissimus Dorsi muscle gene expression was analyzed using Agilent porcine transcriptome microarrays and clusters of genes displaying similar expression profiles were identified using a modified maSigPro clustering algorithm. Anabolic agents increased carcass (p = 0.002) and muscle weights (Vastus Lateralis: p < 0.001; Semitendinosus: p = 0.075). Skeletal muscle mRNA expression of serine/one-carbon/glycine biosynthesis pathway genes (Phgdh, Psat1 and Psph) and the gluconeogenic enzyme, phosphoenolpyruvate carboxykinase-M (Pck2/PEPCK-M), increased during treatment with BA, and to a lesser extent GH (p < 0.001, treatment x time interaction). Treatment with BA, but not GH, caused a 2-fold increase in phosphoglycerate dehydrogenase (PHGDH) protein expression at days 3 (p < 0.05) and 7 (p < 0.01), and a 2-fold increase in PEPCK-M protein expression at day 7 (p < 0.01). BA treated pigs exhibit a profound increase in expression of PHGDH and PEPCK-M in skeletal muscle, implicating a role for biosynthetic metabolic pathways in muscle growth.

An 80-kDa parasporal crystal protein was detected in protein extracts of sporangia of Bacillus popilliae isolated from a diseased larva of the common cockchafer (Melolontha melolontha L.). Amino acid analysis of tryptic peptides revealed significant homology to the Cry2Aa endotoxins of Bacillus thuringiensis. The gene cryBP1 (cry18Aa1), which codes for the parasporal crystal protein, was found in a putative cry operon on the bacterial chromosome, which contains at least one further (smaller) open reading frame, orf1. The 706-aminoacid-long CryBP1 (Cry18Aa1) protein has a predicted molecular mass of 79 kDa and shows about 40% sequence identity to the Cry2 polypeptides of B. thuringiensis. In the light of published observations which suggest that the parasporal crystal proteins of B. popilliae are slightly toxic to their grub hosts, we propose the following survival strategy of B. popilliae. As an obligate pathogen of grubs, B. popilliae germinates in the gut of a grub and the parasporal crystal proteins are released and activated. The activated protein does not cause colloid osmotic lysis but instead damages the gut wall somehow to allow the vegetative cells to enter the hemolymph more easily. By becoming a parasite, B. popilliae can continue to proliferate efficiently while the living grub provides a food supply. This process is in contrast to that of B. thuringiensis, which rapidly kills the insect and is then limited to growth on the larval carcass.The gram-positive, spore-forming bacterium Bacillus popilliae Dutky (14) is the obligate causal agent of milky disease of scarab larvae. The name of the disease comes from the milkywhite appearance of the normally clear hemolymph, which is due to the extremely high number of spores generated in the hemolymph (2 ϫ 10 9 to 5 ϫ 10 9 spores per larva) during the infection of the grubs by B. popilliae (21; for reviews, see references 7, 26, and 37). B. popilliae preparations have been used for more than 50 years in the United States for suppression of Japanese beetle larvae (Popillia japonica Newman) (for a review, see reference 25). In fact, this bacterium was the first microorganism registered in that country as an insecticide.For biological control of grubs, only B. popilliae spore preparations can be used, since vegetative cells rapidly lose viability in the soil. Despite considerable research aimed at achieving efficient in vitro production of spores, only very low levels have ever been attained in the laboratory. The lack of methods to efficiently induce sporulation in vitro has been the major factor preventing more research and development projects for these bacteria (38).During sporulation, B. popilliae forms parasporal crystals in a manner reminiscent of Bacillus thuringiensis, which is wellknown as a specific microbial pesticide for larvae of varieties of Lepidoptera, Diptera, and Coleoptera (23). However, the role of the parasporal crystals in B. popilliae pathology remains unclear. Weiner isolated parasporal bodies from B. popilliae NRRL 2309S, a pathogen of ...

derepression of the fusion gene and of endogeneous Ubx : /3galactosidase staining appears weak anteriorly and strong posteriorly, whereas antibody staining is even throughout. But the extension of the derepressed domain is the same in both cases and most probably corresponds to the addition of the normal Ubx and abd-A expression domains. We conclude that functional abd-A product determines the posterior limit of normal Ubx expression in the visceral mesoderm. Interestingly, neither the second nor the third midgut constriction can form properly in abd-A-mutant embryos (Fig. 2j-/), suggesting that the formation of these constrictions depends on adjacent domains of differential homeotic gene activity in the visceral mesoderm. The Abdominal-B (Abd-B) product functions to down-regulate Ubx expression in the posterior ectoderm 8 • In contrast, we find that an Abd-B null mutation 14 (Abd-BM 1) does not affect Ubx expression in the visceral mesoderm, although the effect of this mutation is clearly apparent in ps13 of the ectoderm (Fig. 2b). We find unexpectedly that, in the absence of functional abd-A product, Abd-B can activate the fusion gene ectopically: {J-galactosidase staining appears in the visceral mesoderm of the posterior midgut in Ubx-abd-A-double mutant embryos (Fig. 2g). This ectopic {J-galactosidase staining is abolished in triple mutants (Ubx-abd-A-Abd-Band nd is therefore dependent on functional Abd-B product (Fig. 2h). The ectopic {Jgalactosidase staining domain probably corresponds to the Abd-B expression domain, implying that abd-A and Abd-B expression coincides in the posterior visceral mesoderm. It appears that Abd-B does not have any repressor function in this germ layer. We have shown that, in the absence of functional Ubx prod

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