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Leptographiumspecies are anamorphs of Ophiostoma,commonly isolated from conifer. There are, however, a small number of these fungi that have been collected from angiosperm hosts. In this study, we describe Leptographium pruni,sp. nov. isolated from the bark of Prunus jamasakurainfested by the bark beetle Polygraphus ssiori.This new species is unusual in having a distinct Sporothrixsynanamorph with ramoconidia. No evidence of a teleomorph was found, but a high level of tolerance to the antibiotic cycloheximide and the presence of a Sporothrixsynanamorph suggest that L. pruniis an Ophiostomaanamorph. Analysis of sequence data for the domain 1 region of the LSUrDNA operon also supports the phylogenetic relationship of L. pruniwith Ophiostoma.In addition, sequence data suggest that L. pruniis related to other species of Leptographiumrather than Pesotumspecies with distinct Sporothrixsynanamorphs.

The variable region of immunoglobulin heavy chain is encoded by three separate genes on the germline genome: variable (VH), diversity (DH) and joining (JH) genes. Most human DH genes are encoded in 9‐kb repeating sequences. We determined the nucleotide sequence of a 15‐kb DNA fragment containing more than one and a half of these repeating units, and identified 12 different DH genes. Based on the sequence similarities of DH coding and the surrounding regions, they can be classified into six different DH gene families (DXP, DA, DK, DN, DM and DLR). Nucleotide sequences of DH genes belonging to different families diverge greatly, while those belonging to the same families are well conserved. Since the 9‐kb DNA containing the six DH genes are multiplied at least five times, the total number of DH genes must be approximately 30. These DH genes are sandwiched by 12‐nucleotide spacer signals. Most of the somatic DH sequences found in the published VH‐DH‐JH structures (the somatic DH segment being defined as the region which is not encoded either by germline VH or JH gene) were assigned to one of the germline DH genes. Other than these typical DH genes, however, we found a new kind of DH gene (which we termed DIR) the spacer lengths of whose neighbouring signals were irregular. The DIR gene appears to be involved in DIR‐DH or DH‐DIR joining by inversion or deletion. Two of the somatic DH sequences were assigned to the DIR genes. Long N segments might, therefore, originate from DIR genes.

Continued investigation of murine leukemia (P-388) active fractions from the African marine worm Cephalodiscus gilchristi has resulted in the discovery of cephalostatins 18 (1b) and 19 (1c). The structures were determined by interpretation of their highfield (500 MHz) ¹H, ¹³C, and 2D NMR and HRMS. Both of these new methoxy steroidal alkaloids exhibited strong activity against the murine P-388 lymphocytic leukemia cell line (ED50 ca. 10^-3 μg/mL), a mini panel of human cancer cell lines (GI50 <10^-3 μg/mL), and the U.S. National Cancer Institute's 60 human cancer cell line panel (mean panel GI50 ca. 10^-9 M).

The entire human pepsinogen C gene has been isolated from a cosmid genomic library. The nucleotide sequences of all the exons and the 5‘- and 3‘-flanking regions of the gene are presented. The organization of the gene is fundamentally compatible with those of other aspartic proteinases, allowing us to conclude that the genes of these aspartic proteinases including pepsinogen C are derived from a common ancestral gene. The predicted 388-residue amino acid sequence of human pepsinogen C consists of a signal sequence of 16-amino acid residues, an activation peptide of 43 residues, and the mature pepsin of 329 residues containing the two active-site aspartic acids. In the light of present notions about eukaryotic gene expression, possible regulatory roles of the oligonucleotide DNA sequences in the promoter region of the gene are discussed.

The variable region of immunoglobulin heavy chain is encoded by three separate genes on the germline genome: variable (VH), diversity (DH) and joining (JH) genes. Most human DH genes are encoded in 9‐kb repeating sequences. We determined the nucleotide sequence of a 15‐kb DNA fragment containing more than one and a half of these repeating units, and identified 12 different DH genes. Based on the sequence similarities of DH coding and the surrounding regions, they can be classified into six different DH gene families (DXP, DA, DK, DN, DM and DLR). Nucleotide sequences of DH genes belonging to different families diverge greatly, while those belonging to the same families are well conserved. Since the 9‐kb DNA containing the six DH genes are multiplied at least five times, the total number of DH genes must be approximately 30. These DH genes are sandwiched by 12‐nucleotide spacer signals. Most of the somatic DH sequences found in the published VH‐DH‐JH structures (the somatic DH segment being defined as the region which is not encoded either by germline VH or JH gene) were assigned to one of the germline DH genes. Other than these typical DH genes, however, we found a new kind of DH gene (which we termed DIR) the spacer lengths of whose neighbouring signals were irregular. The DIR gene appears to be involved in DIR‐DH or DH‐DIR joining by inversion or deletion. Two of the somatic DH sequences were assigned to the DIR genes. Long N segments might, therefore, originate from DIR genes.

A recombinant clone, which covers the pepsinogen gene in a single insert, has been isolated by screening a library of human genomic DNA, using a swine pepsinogen cDNA as a probe. Sequence analysis of coding DNA segments of the clone revealed that the pepsinogen gene occupies approximately 9.4-kilobase pairs of the genomic DNA and is separated into nine exons by eight introns of various lengths. The predicted amino acid sequence of human pepsinogen consists of 373 residues and is 82% homologous with that of swine pepsinogen. In addition, the predicted sequence contained a single sequence of 15 amino acid residues at the NH2 terminus, showing that the protein is synthesized as prepepsinogen. The structure of the gene, in which two homologous sequences including the two active site aspartyl residues of pepsin are present in different coding segments, is in support of the view that the pepsinogen gene evolved by duplication of a shorter ancestral gene.

The entire rat pepsinogen C gene has been isolated from a rat genomic library, using the rat pepsinogen C cDNA as a probe. Southern blot analysis showed that there exists at least two rat pepsinogen C genes. The nucleotide sequences of the coding regions and the 5′- and 3′-flanking regions of one of the rat pepsinogen C genes have been determined. This gene is split into 9 exons interrupted by eight intervening sequences. The 5′-flanking region is similar to that of the human pepsinogen C gene, but only the former has the core sequence of the Sp1 binding site.

cDNA of rat pepsinogen C (PGC) hybridizes to, among others, a 3.2-kb band in Southern blot analysis of BamHI-cleaved human genomic DNA. This property was employed to localize the human PGC gene. Use of flow-sorted human chromosomes and 12 human × mouse somatic cell hybrid lines demonstrated that the gene is located on chromosome 6.

The title compounds, e.g. (III), (V) and (VII), and pyrazolo(1,5‐a)quinolines and ‐(5,1‐a)isoquinolines are synthesized by the procedure described in the scheme.

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