Induction of HSV-gD2 specific CD4(+) cells in Peyer's patches and mucosal antibody responses in mice following DNA immunization by both parenteral and mucosal administration

A DNA vaccine encoding glycoprotein D (gD) of herpes simplex virus type 2 (pHSV-gD2) was injected via parenteral and mucosal routes to determine the optimal route of delivery for immune stimulation. Generation of distal mucosal immunity following parenteral vaccination was also evaluated. While all routes of DNA vaccine administration resulted in systemic cellular and humoral responses, the intra-muscular (i.m.) and intra-dermal (i.d.) routes of delivery produced the highest responses. Furthermore, i.m. and i.d. routes produced mucosal humoral responses that were comparable to those obtained via mucosal routes. Specific pHSV-gD2 PCR signals were detected in the Peyer's patches (PP) within hours following vaccination and antigen specific IgA was detected in secretions and supernatants from gut fragment cultures. Furthermore, antigen specific CD4(+) cells were found in PP. Collectively these results suggest that the DNA vaccine stimulated a response in the PP, a major inductive site for mucosal responses.

Sequence alignment of the G-protein coupled receptor superfamily

The multitude of G-protein coupled receptor (GPR) superfamily cDNAs recently isolated has exceeded the number of receptor subtypes anticipated by pharmacological studies. Analysis of the sequence similarities and unique features of the members of this family is valuable for designing strategies to isolate related cDNAs, for developing hypotheses concerning substrate-ligand and receptor-effector interactions, and for understanding the evolution of these genes. We have compiled and aligned the 74 unique amino acid sequences published to date and review the present understanding of the structural motifs contributing to ligand binding and G-protein coupling.

Alternative transcripts of the rat and human dopamine D3 receptor

A cDNA for the rat dopamine D3 receptor containing a 113 bp deletion has been isolated. The segment deleted, encompassing the first extracellular loop and third transmembrane domain, alters the reading frame, introducing 19 amino acids not found in the full length receptor followed by a premature stop codon. This novel mRNA encodes a 109 amino acid protein containing two putative transmembrane domains. A similar variant cDNA for the human D3 receptor has also been identified.

Evidence for a new tumor-suppressor gene involved in gastrointestinal malignancies

Inactivation or loss of tumor-suppressor genes is believed to lead to the development or progression of malignancies. To determine whether a tumor-suppressor gene is located on chromosome 8, DNA was extracted from tumor and normal tissue of colorectal, gastric, and pancreatic specimens, and allele loss was investigated by Southern hybridization techniques with the chromosome 8 probe D8S7. Twenty-five percent of pancreatic carcinomas, 50% of gastric carcinomas, and 50% of colorectal carcinomas were found to have lost an allele on chromosome 8. These findings suggest the presence of a tumor-suppressor gene on chromosome 8, which is involved in colorectal carcinoma, gastric carcinoma, and pancreatic carcinoma. Definition of the frequency with which this tumor-suppressor gene is involved in gastrointestinal malignancies will await the study of many patients who are classified as informative and the use of multiple probes for chromosome 8.

Distribution of dopamine D2 receptor mRNA splice variants in the rat by solution hybridization/protection assay

We investigated the distribution of the two dopamine D2 receptor mRNA splice variants in the rat using a sensitive and quantitative solution hybridization/nuclease protection assay. In all brain and endocrine regions studied, both splice variants were detected and the mRNA of the longer form (D2L) was more abundant than that of the shorter form (D2S). The lowest percentages of D2S were found in the pituitary and adrenal glands.

The improbability of irradiated spermatozoa as gene transfer vectors in chickens

It is concluded that chromatin fragments derived from irradiated chicken spermatozoa are not viable vectors for gene transfer. In three experiments conducted at sequential intervals over a period of 1 1/2 years, no marker traits were found in 1,065 G0 progeny from irradiated spermatozoa of Minnesota Dominant Marker males inseminated into recessive Rhode Island Red and White Leghorn females. The inability to secure transformants is ascribed to the following factors: a maximum of five and probably fewer potential vector fragments for each G0 progeny because of irradiation effect on spermatozoan ability to enter the germinal disc; uncertainty of DNA integrity from highly irradiated chromatin; no known mechanism for release of chromatin fragments from irradiated spermatozoa supernumerary pronuclei; and the uncertainty of selective integration into the zygotic nucleus.

Drosophila nucleosomes contain an unusual histone-like protein

Mononucleosomes prepared from Drosophila melanogaster nuclei contain the four core histones H2A, H2B, H3, and H4 plus an additional histone-like, acid-soluble, chromosomal protein. It is probably the protein designated D2 by Alfageme et al. [Alfageme, C.R., Zweidler, A., Mahowald, A. & Cohen, L.H. (1974) J. Biol. Chem. 249, 3729-3736]. D2 elutes with histone H2A from a Bio-Gel P-100 column, but can be distinguished electrophoretically from H2A and from the other standard Drosophila core histones. The amino acid composition of D2 resembles the compositions of H2A and H2B. However, peptide mapping reveals that D2 is not a simple sequence variant of either H2A or H2B. D2 is present in nuclei from embryos and adult heads, and thus is not restricted to a narrowly defined developmental period. It is present in D. melanogaster and D. virilis, and thus appears to be conserved during the evolution of Drosophila. D2 is present in D. melanogaster chromatin with an approximate frequency of one molecule per five nucleosomes, and must therefore be associated with a subset of nucleosomes. The function of this protein is not known. Its presence in nucleosomes, evolutionary conservation, and comparatively large abundance all suggest that it is an important nucleosomal element. It will be interesting to learn whether this histone-like protein is encoded in a subset of the Drosophila histone gene cluster or is encoded separately.

Correlation between phosphorylated H1 histones and satellite DNAs in Drosophila virilis

Drosophila virilis DNA contains satellites I, II, and III. D. novamexicana DNA contains satellite I. D. virilis H1 histone contains subfractions a, b, c, d, and e; D. novamexicana H1 contains subfractions a, b, and c. Therefore, satellites II and III might be correlated with H1d and H1e. To test the validity of this correlation, the H1 histones of polytene nuclei, which contain less than 1% satellite DNA, were analyzed. Polytene nuclei of D. virilis contain substantially decreased levels of H1c and H1e and marginally decreased levels of H1d. Polytene nuclei of D. novamexicana contain decreased levels of H1c.H1c is correlated with satellite I (common to D. virilis and D. novamexicana); H1e is correlated with satellites II and III; H1d is not correlated with any satellite DNA, because its level is virtually unchanged in polytene cells lacking detectable amounts of satellite DNA. Alkaline phosphatase digestion of the H1 histones reveals that H1c is the phosphorylated form of H1b and H1e is the phosphorylated form of H1d. Therefore, the under-replication of satellite DNAs is correlated with the decreased phosphorylation of H1 histones. In vitro, D. virilis H1 histones preferentially bind D. virilis DNAs in the progression III greater than II greater than I greater than main band, whereas D. virilis core histones do not preferentially bind any D. virilis DNA. As an extension of these results, we suggest that phosphorylated H1 histones bind D. virilis satellite DNAs in vivo and are involved in the compaction of heterochromatin.

Cytogenetic and complementation analyses of recessive lethal mutations induced in the X chromosome of Drosophila by three alkylating agents

Salivary-gland chromosomes of 54 methyl methanesulphonate- and 50 triethylene melamine-inducedX-chromosome recessive lethals inDrosophila melanogasterwere analysed. Two of the lethals induced by the mono-functional agent and 11 of those induced by the polyfunctional agent were found to be associated with detectable aberrations. A complementation analysis was also done on 82 ethyl methanesulphonate- and 34 triethylene melamine-induced recessive lethals in thezeste-whiteregion of theXchromosome. The EMS-induced lethals were found to represent lesions affecting only single cistrons. Each of the 14 cistrons in the region known to mutate to a lethal state was represented by mutant alleles, but in widely different frequencies. Seven of the TEM-induced lethals were associated with deletions, only one of which had both breakpoints within the mapped region. Twenty-six of the 27 mutations in which only single cistrons were affected were mapped to 7 of the 14 known loci. One TEM- and two EMS-induced mutations were alleles representing a previously undetected locus in thezeste-whiteregion.