A reevaluation of the amino acid sequence of human follitropin beta-subunit

A collaborative study from two laboratories has been undertaken to re-evaluate the human follitropin -subunit sequence (hFSH), since areas of uncertainty remain in the wake of two earlier reports. The first report was by Shome and Parlow (1974). The second, by Saxena and Rathnam (1976), proposed revisions for sequence not definitively placed in the first study, as well as some differences in other placements. We have re-examined the sequence of the hFSH with more recent methodology. This has led to revision of certain areas of the sequence and resolution of differences between the two earlier proposals. Specifically, an-Ile-Ser- is established at 21–22, Asp at 41, Arg at 44, Lys at 46, and Glu at 111. These were areas of disagreement in the earlier proposals. A definitive placement of the residues around tryptophan-27 has now been obtained by three laboratories. C-terminal heterogeneity was observed with subunits ending at residue 107, 109, or 111. N-terminal heterogeneity has been observed in all preparations examined to date. A significant population of molecules with a proteolytic nick between residues 38–39 is noted. This is very likely an artifact of the collection and processing. The preparations examined in the present studies showed no evidence of residues 112–118 proposed by Saxena and Rathnam.     

Effects of itraconazole on the sporocysts wall of the entomopathogenic fungi Ascosphaera apis as revealed by the scanning electron microscope

The young sporocysts had a wrinkled sporocyst wall, numerous papillae on the wall surface and the wall was granular and porous. In the itraconazole-treated culture, the walls of the young sporocysts were also wrinkled, but the characteristic papillae were replaced by larger lumps which were densely packed and coated the entire surface of the sporocyst wall. The mature sporocysts walls were smooth and possessed numerous papillae. In the itraconazole-treated culture, the walls of mature sporocysts walls were also smooth but possessed densely packed larger lumps instead of papillae. At higher magnification, each of the lumps were found to consist of numerous globules. No pores were observed as they were in the normal sporocyst wall.     

The secondary structure of ribonuclease P RNA, the catalytic element of a ribonucleoprotein enzyme

Secondary structure models for the ribonuclease (RNAase) P RNAs of Bacillus subtilis and E. coli were derived by a phylogenetic comparative analysis of published sequences as well as four novel ones. The RNAase P RNA genes from Bacillus megaterium, Bacillus brevis, Bacillus stearothermophilus, and Pseudomonas fluorescens were cloned, sequenced, and compared with the other available sequences. Regions of pairing were identified by the occurrence of homologous complementary sequences that vary among the compared molecules. A common core of primary and secondary structure can be identified in all these RNAase P RNAs. The previously noted striking differences between the Bacillus and the enteric RNAase P RNAs arise not only from point mutations, but from the addition or deletion of structural domains. The primary and secondary structural features that are common to all of the RNAase P RNAs are likely to be the elements involved in the binding and cleavage of tRNA precursors, and in the interaction with the RNAase P protein.     

Zero-stress states of arteries

The no-load configuration of a living organ is, in general, not the zero-stress state. The difference can be revealed by cutting up an unloaded organ to such an extent that the stress becomes zero in the tissue everywhere. For the aorta, it is shown that the configuration of the zero-stress state differs considerably from being a cylindrical tube. It is, in fact, an open sector with opening angles varying along the arterial tree. This article presents data on the zero-stress state in the arteries of the rat in normal condition.     

Interactions of porphyrins with purified DNA and more highly organized structures

Studies of the solution properties of gold(III)tetrakis(4-N-methylpyridyl) porphine and its DNA binding characteristics have been conducted utilizing uv/vis absorption spectroscopy, circular dichroism (CD), Mossbauer spectroscopy, and temperature-jump relaxation techniques. These studies indicate that over the concentration range considered this water soluble gold(III) porphyrin does not aggregate, binds axial ligands only weakly with a preference for soft Lewis bases, and is capable of intercalation into nucleic acids of appropriate base pair content. The interaction of this and several other porphyrins with the synthetic polynucleotide poly(dA-dC).poly(dT-dG) has been studied. Spectroscopic signatures for intercalation were found for those derivatives not having axial ligands. Intercalation into chromatin in vitro can also occur with those porphyrins and metalloporphyrins which do not have axial ligands. Finally, studies utilizing microinjection techniques indicate that once within the cell, tetrakis(4-N-methylpyridyl)porphine tends to localize in the nucleus.     

Microtubule and microfilament distribution and tubulin content in the cell cycle of Indian muntjac cells

Using DAPI, rabbit antitubulin antibody, FITC-labeled goat anti-rabbit IgG, and TRITC-phalloidin to stain individual cells, the microspectrophotometric analysis showed that three markers that represent the nucleus, microtubules (MT), and microfilaments (MF), respectively, could be recognized in individual cells without interference. The phase of the cell cycle was determined by DNA content. We found that in Indian muntjac (IM) cells, the amount of tubulin in G2 and M phases was about twice as much as that in G1 phase. In G2 cells, the cytoplasmic microtubule complex (CMTC) became denser than in G1 cells. The cytoplasmic MT extent in basically the same orientation as MF bundles in interphase. The regions where the MT is denser also have a denser MF distribution.     

兰萼丙素的结构

从北京地区产兰萼香茶菜[Rabdosia japonica (Burm. f.)Hara var.glaucocalyx(Maxim.)Hara]叶中分得三个对映-贝壳杉烯二萜化合物,其中二个为已知物兰萼甲素(2)和乙素(3),另一个为新化合物,命名为兰萼丙素,经光谱和化学方法证明,其结构为对映-7β,14α,15α-三羟基-16-贝壳杉烯-3-酮(1)。     

Human immune responses to major human cytomegalovirus glycoprotein complexes.

Sera from both human cytomegalovirus (HCMV)-seropositive adults and infants with congenital HCMV infection recognized two major HCMV glycoprotein complexes. However, proliferative responses of peripheral blood mononuclear cells to these complexes varied among seropositive adults and were not detected in any of the infants. Thus, these glycoproteins alone may not be sufficient to develop a subviral HCMV vaccine.     

Mutagenicity of gossypol analyzed by induction of meiotic micronuclei in vitro

Chromosome breakage caused by mutagens in male germ cells can be analyzed by micronucleus induction during meiotic division. This can be followed in vitro by culturing seminiferous tubular segments from stages of the epithelial cycle that contain late pachytene and diakinetic primary spermatocytes. We studied the mutagenic potential of a male contraceptive, gossypol, in this test system using adriamycin (10 ng/ml) as a reference mutagen. A small but significant increase in the frequency of micronuclei was induced with concentrations of 10 and 20 micrograms/ml of gossypol, while cytotoxic effects appeared at concentration of 20 micrograms/ml and were evident at 50 micrograms/ml. Analysis of meiotic micronucleus induction in vitro seems to be a sensitive test system of male germ-cell mutagenesis, but further studies on the possible mutagenic effects of gossypol are needed.