Somatic hybrids between Solanum brevidens and Solanum tuberosum: Expression of a late blight resistance gene and potato leaf roll resistance

Hexaploid somatic hybrids resulting from mesophyll protoplast fusions between Solanum brevidens Phil., PI 218228, and Solanum tuberosum L., PI 203900 were tested for late blight resistance using two races of Phytophthora infestans Monte., de Bary. The S. tuberosum parent was a late blight differential possessing the R4 gene which confers resistance to race 0. The S. brevidens parent is resistant to potato leaf roll virus. Inoculations with both compatible (race 1.3.4.5) and incompatible (race 0) races of P. infestans clearly demonstrated the expression of the late blight resistance gene in all of the hybrid progeny tested. Most of the hybrids tested were also resistant to potato leaf roll virus (PLRV), indicating that the S. brevidens genes for PLRV resistance were present and expressed.     

On the variability of “flexion creases” in the distal plantar areas of newborns

The plantae of 83 male and 95 female healthy, full-term Caucasian newborns from Austria (gestational age 235–301 days) were photographed and the flexion creases in the distal part were examined. Analysis of the creases was done under four different aspects, the main evaluation based on a scheme of nine creases introduced by Schenk and Patzer (1959). Two transversal (No. 1 and No. 9) and three longitudinal (Nos. 3, 6, and 7) creases are always or predominantly present, a finding corresponding with the data of Schenk on 52 male and 48 female newborns from Germany. In addition, the nine plantar creases were evaluated according to six degrees of expression, and some typical crease combinations are shown. Bilateral and bisexual similarity prevails. The results of this study might serve investigations of different populations and of medical disorders.     

Somatovariants of females from Northern India

On the basis of the somatometric data of a series of healthy females (126 individuals 20-30 years old; 219 individuals 31-49 years old) from Northern India (Punjab) a new method is demonstrated for the indication of habitus variants. This method is based on only three measurements. In this study stature, weight and biepicondylar breadth of the humerus were used. This simple method permits instant visualization of the actual class-memberships of each individual (somatovariants). The applicability of the method is shown for intragroup and intergroup comparison. The results are discussed with respect to possible indications of pathologic cases, undernourishment, population specific criteria and age-depending effects. The authors emphasize, however, that this method still needs further elaboration.     

Effect of parasympathetic denervation on acetylcholine levels in the rat parotid gland. Is there an extraneuronal pool of acetylcholine?

Parasympathetic denervation of the rat parotid gland by avulsion of the auriculotemporal nerve caused a marked and lasting decrease in gland weight. Parasympathectomy did not change the levels of choline in the gland but decreased by 60% the levels of acetylcholine (ACh) ten days after surgery and 65% at 28 days. It is puzzling that relatively high levels of ACh remained after parasympathetic denervation. The presence of additional cholinergic nerves that innervate the gland, or pass through it en route to other structures may account for some of the remaining ACh. Also, Schwann cells from denervated nerves might have contributed to some of the ACh. The existence of an extraneuronal source of ACh is considered.     

Sucrase-isomaltase: a stalked intrinsic protein of the brush border membrane

The isolation and purification of sucrase-isomaltase from brush border membrane is described and the physicochemical properties of the pure enzyme are discussed. Our present understanding of the mode of association of the intrinsic membrane protein sucrase-isomaltase with the brush border membrane will be the central point of this contribution. The assembly of sucrase-isomaltase into phospholipid bilayers has been reported to result in a model membrane system which resembles the "native" brush border membrane as regards the mode of lipid-protein interaction. The physicochemical properties of this reconstituted model membrane will be compared to the in vivo situation as represented by brush border membrane vesicles routinely isolated from small intestinal brush borders. The biosynthetic mechanism will be discussed.     

Requirements for antiribosomal activity of pokeweed antiviral protein

It has been known for some time that pokeweed antiviral protein acts by enzymatically inhibiting protein synthesis on eucaryotic ribosome systems. The site of this action is known to be the ribosome itself. In this paper we show that the pokeweed antiviral protein reaction against ribosomes is a strong function of salt concentrations, where 160 mM K⁺ and 3 mM Mg²⁺ retards the reaction, while 20 mM K⁺ and 2 mM Mg²⁺ allows maximum reaction rate. It is also shown, however, that an unidentified protein in the postribosomal supernatant solution, together with ATP, allows the ribosome to be attacked even in the presence of high salt. Kinetic analysis of the antiviral protein reaction has been carried out under both sets of conditions, and reveals that the turnover number for the enzyme is about 300–400 mol/mol per min. in each case. The K_m for ribosomes is 1 μM in the presence of low salt and 0.2 μM at higher salt in the presence of postribosomal supernatant factors plus ATP. The antiviral protein reaction is also shown to be pH dependent and is controlled by a residue with pK_a value of approx. 7.0, apparently a histidine. Stoichiometric reaction of the enzyme with iodoacetamide results in a significant loss of antiribosomal activity.     

Order-disorder phase transition and lipid dynamics in rabbit small intestinal brush border membranes. Effect of proteins

The total lipids extracted from brush border membranes form smectic lamellar phases when dispersed in water. 31P broad-band nuclear magnetic resonance (NMR) shows that between body temperature (37 degrees C) and freezing of the solvent, the extracted lipids form bilayers with the lipid molecules undergoing fast anisotropic motion. This is also true for the lipids present in the brush border membrane. The electron spin resonance (ESR) results obtained with various hydrophobic spin probes incorporated in either brush border vesicle membranes or their extracted lipids are consistent with this interpretation. By use of a variety of chemically different spin-labels, the temperature dependence of brush border membranes and their extracted lipids was probed. The temperature dependence of various ESR spectral parameters shows discontinuities that, by comparison with differential scanning calorimetry, are assigned to a lipid thermotropic phase transition. Differential scanning calorimetry shows that the lipid in brush border membranes undergoes a broad, reversible phase transition of low enthalpy between 10 and 30 degrees C, with a peak temperature of about 25 degrees C. Hence, the brush border membrane of rabbit small intestine functions in the liquid-crystalline state, well above the peak temperature and also above the upper limit of the lipid phase transition. Therefore, in itself, the thermotropic lipid phase transition is unlikely to play a physiological role. The low enthalpy of the lipid phase transition, indicative of a lack of cooperativity, is primarily attributed to the relatively high cholesterol content and to heterogeneity in the lipid composition of this membrane [Hauser, H., Howell, K., Dawson, R. M. C., & Bowyer, D. E. (1980) Biochim. Biophys. Acta 602, 567-577].(ABSTRACT TRUNCATED AT 250 WORDS)     

Classification of cell types: Agglutination and chromosomal properties

Summary The properties of agglutination by plant lectins, along with chromosome patterns, were examined in a variety of mammalian cell types. Untransformed adult and embryonic cells in culture, direct mouse spleen cell preparations, SV40-transformed 3T3 cells, and trypsinized 3T3 cells were all highly agglutinable with concanavalin A and with wheat germ agglutinin. In contrast, untreated cells of the contact-inhibited 3T3 line were alone among the cells tested in their low agglutinability. Chromosome analysis of the cultured cells showed that karyotypic variation from the diploid to an aneuploid state in mouse and rat embryo cultures was not accompanied by a change in agglutinability. Adult rat lung, adult monkey kidney, and embryonic human lung cells, which were all highly agglutinable, showed the normal diploid pattern. Thus, agglutination of cells by plant lectins appears to be a cellular property often associated with non-neo-plastic cells. This investigation was supported by Grants CA-12503 and ES-00260 from the National Institutes of Health, United States Public Health Service.