Hamster pulmonary endocrine cells with positive immunostaining for calbindin-D28K

 We have examined the distribution of calcium-binding proteins (CaBPs) in adult and fetal lungs of Syrian golden hamsters (Mesocricetus auratus) using immunostaining with confocal laser microscopy and electron microscopy. Single and grouped (neuroepithelial body; NEB) endocrine cells were distributed from bronchi to alveolar ducts in the adult lung. Serial frozen sections immunostained for CaBPs in combination with immunostaining for endocrine markers such as calcitonin gene-related peptide, serotonin, PGP9.5, and synaptophysin revealed that positive immunostaining for calbindin-D_28K (CB-D28K) was seen in single endocrine cells and NEBs. However, other so-called EF-hand family CaBPs, parvalbumin and calretinin, were not detected. Electron microscopically, positive immunoreaction for CB-D28K was mainly in the organelle-free cytoplasmic matrix of endocrine cells, and partly in nuclei and associated with secretory granules and endoplasmic reticulum. In fetal developing lungs, endocrine cells appeared first on gestational day 13, and they were positive for all the endocrine markers used. However, pulmonary endocrine cells were positively immunostained for CB-D28K from gestational days 15 and 16 onward. In summary, our observations suggest that CB-D28K is a useful marker for endocrine cells of the lung, and CB-D28K could function as a mediator of endocrine stimulation or calcium homeostasis in pulmonary endocrine cells. Accepted: 17 June 1997     

Cloning of cDNA for Vitellogenin of the Parasitoid Wasp, Pimpla nipponica (Hymenoptera: Apocrita: Ichneumonidae): Vitellogenin Primary Structure and Evolutionary Considerations

The cDNA for vitellogenin (Vg) of the parasitoid wasp Pimpla nipponica (Hymenoptera: Apocrita) was cloned and sequenced.¹ The deduced amino acid sequence with 1807 residues was obtained. The N-terminal 20 amino acids chemically determined for vitellin (Vn) agreed completely with the deduced 20 amino acids that follow the 16 amino acid residues for putative signal peptide. The cDNA clone for the Vg of the turnip sawfly Athalia rosae (Hymenoptera: Symphyta), previously obtained and partially sequenced, was also completely sequenced and the amino acid sequence deduced. Amino acid sequences were compared between these two species and also with known Vg sequences from other insects. Common to all these insects is the presence of two long regions with relatively well-conserved amino acid sequences, one near the N-terminal extending 267–282 residues (including two cysteines at conserved locations), and the other starting at position 450 to 655 and extending 279–283 residues, and of a region at the C-terminal extending some 200 residues (about 250 in Aedes aegypti due to the presence of a serine-rich stretch) with 10 cysteines at conserved locations. A molecular phylogenetic tree was constructed.     

COMPARATIVE MORPHOLOGY, CROSSABILITY, AND TAXONOMY WITHIN THE CALOGLOSSA CONTINUA (DELESSERIACEAE, RHODOPHYTA) COMPLEX FROM THE WESTERN PACIFIC

Systematic studies were undertaken on the Caloglossa continua ( Okamura) King et Puttock complex from Japan, Singapore, and Australia, based on morphology and reproductive compatibility. Specimens from Japan had two to six cell rows derived from a nodal axial cell, at the margin opposite the branch, whereas those from Australia possessed only a single cell row. Specimens from Singapore formed one to four cell rows per nodal axial cell and always contained at least one single cell row on any one thallus. These differences were maintained in cultured materials over a range of temperatures or salinities. Type material of C. continua had the same morphology as the Japanese specimens in this study. Carpospores discharged from the Japanese isolate germinated at 10°C, whereas those from Singapore and Australia died at this temperature. In hybridization experiments, the Japanese entity was completely nonfertile with both the Singaporean and Australian isolates. Many pseudocystocarps were produced in the crossing between the male from Australia and the female from Singapore, although the reciprocal combination did not produce any such structures. On the basis of the discontinuous morphology coupled with the complete reproductive isolation, the entities from Singapore and Australia are described here as C. monosticha sp. nov. The entities with multiple cell rows likely expanded their geographic range from tropical regions, where the majority of Caloglossa species are now distributed, to high-latitude regions, and such an expansion would be associated with acquiring low-temperature tolerance .     

Plant-wide names for partial cDNA sequences of rice usingBlast and4th dimension

A total of 687 DNA sequence accessions from the Mendel database (release 1.04, 3 November 1994) assigned standardized designations for plant genes and gene products were used in aBLAST similarity search of 7557 rice partial cDNA sequences and 287 other rice sequences from the Japanese Rice Genome Research Program. We describe procedures for data manipulation, import and export from and to Macintosh and Unix, and the use of 4th Dimension relational database management system (RDBMS) in data processing. Altogether 275 sequences showed strong similarity hits. Using the CPGN nomenclature, we assign putative designations for genes and gene products. Assignments include representatives of 26 gene products, including 58 cDNA sequences similar to α-tubulins (TubA), 23 similar to β-tubulins (TubB) and 51 similar to cytosolic subunit C of glyceraldehyde-3-phosphate dehydrogenase (NAD) (GapC). The results of the similarity searches are listed and are also available electronically. The assignments have been submitted to the CPGN working groups for verification and for later inclusion in the GenBank/EMBL/DDBJ sequence databases, which will include the standardized designations in the accession data fields. Member of the ISPMB Commission on Plant Gene Nomenclature, representing the Rice Genome Research Program of Japan. Reprint requests to T. Sasaki.     

Electron microscopic study of endogenous peroxidase activity in human liver macrophages

We evaluated the conditions of fixation for ultrastructurally demonstrating the endogenous peroxidase (PO) activity of macrophages in biopsied human liver. The application of microwaving and immersion fixation with tannic acid and aldehydes allowed excellent visualization of PO activity in the nuclear envelope (NE), rough endoplasmic reticulum (rER), and cytoplasmic granules (CG), with good preservation of cellular ultrastructures. The macrophages with PO activity showed one of the following five patterns of PO localization: positive in both the NE and rER but negative in the CG (type 1); negative in both the NE and rER but positive in the CG (type 2); negative in the NE but positive in both the rER and CG (type 3); positive in all three (type 4); PO negative (type 5). The type 1 cells resembled typical Kupffer cells, type 2 cells monocytes, and type 3 and 4 cells the exudate-resident macrophages considered to be a transitional form between exudate and resident macrophages. Type 5 cells may also be a transitional form between the exudate and resident macrophage, or an end-stage macrophage derived from exudate macrophages which have lost their PO activity. Tannic-acid-aldehyde immersion fixation with microwaving may be a useful method in the study of the PO activities of macrophages in biopsied human liver specimens.     

Alkaline phosphatase reactivity in rabbit airway epithelium: a potentially useful marker for airway basal cells

The purpose of this study was to investigate alkaline phosphatase (ALPase) reactivity in rabbit airway epithelial cells. Acetone-fixed, methyl benzoate and xylene-cleared (AMeX-treated) paraffin sections of trachea, bronchus, and lung tissue were stained by an azo dye coupling method for ALPase and examined by light microscopy. Electron histochemical staining was also performed in order to study the sensitivity and specificity of reactivity in each cell type. ALPase reactivity at the light microscopic level was observed exclusively in trachco-bronchial basal cells, and not in bronchiolar basal cells. By electron microscopy, ALPase reactivity was noted in 97.9% of basal cells in the trachea, 97.0% of basal cells in the bronchus, and 94.5% of basal cells and 15.4% of Clara cells in the bronchiole. This was also true for dispersed tracheal epithelial cells. Reactivity was rarely observed in ciliated cells, non-goblet-type secretory cells, and undetermined cells. The reactivity was heatlabile, levamisole-sensitive, and of a non-specific type. These findings indicate that basal cells of rabbit trachea and bonchus have fairly high specificity for ALPase of a non-specific isozyme (92.2% and 95.6%, respectively). Therefore, ALPase is considered to be a useful marker for these cells.     

Factors affecting formation of micronucleus-like structures after colchicine treatment of Trichoderma reesei

Micronucleus-like structures were produced in Trichoderma reesei only when 0.1% colchicine treatment was used to enhance nuclear division. The average DNA content of these small nuclei was 30% that of the normal nuclei, indicating that they were aneuploid nuclei. Such small nuclei may be useful in transferring small amounts of DNA into protoplasts.The authors are with the Department of Food Technology, Faculty of Horticulture, Minamikyushu University, Takanabe-Cho, Hibarigaoka, Miyazaki 884, Japan;     

Purification and properties of ATPase from an alkalophilic Bacillus

ATPase was purified from an alkalophilic Bacillus. The enzyme has a molecular weight of 410,000 and consists of five types of subunits of molecular weights of 60,000 (α), 58,000 (β), 34,000 (γ), 14,000 (δ), and 11,000 (?). The subunit structure is suggested to be α₃β₃γδ?. The enzyme is activated by Mg²⁺ and Ca²⁺. The pH optima of the enzyme with 0.1 and 2.0 mm Mg²⁺ are 9 and 6, and those with 1 and 10 mm Ca²⁺ are 8–9 and 7, respectively. Ca²⁺-ATPase hydrolyzes only ATP, whereas Mg²⁺-ATPase hydrolyzes GTP and, to a lesser extent, ATP. The values of V and K_m of the enzyme with ATP in the presence of 10 mm Ca²⁺ or 0.6 mm Mg²⁺ at pH 7.2 are 17 or 0.5 units/mg protein and 1.2 or 0.3 mm, respectively. The enzyme with Mg²⁺ is appreciably activated by HCO^?₃. Relationship of the ATPase to the active transport system in the bacterium is suggested.