Anther and tissue culture-induced grain chalkiness and associated variants in rice

Rice, Oryza sativa, plants regenerated from anther culture with and without in vitro selection pressure were evaluated for chalky seed. Progeny evaluated included 21 spontaneously doubled haploids selfed 4 times, progeny from plants regenerated from S-aminoethylcysteine resistant callus selfed 4 times and backcrosses of both types to the parental type. All lines with in vitro histories had higher seed chalkiness than the controls both in the intensity of chalkiness and in the number of seeds expressing the character. The full range of intensity and amount of chalkiness was expressed in the progeny. The average intensity of anther/tissue culture-derived progeny was 4–5, based on a scale of 1 (translucent) to 10 (fully opaque), and the average amount of chalkiness within plants sampled was 50–75 percent. The chalky characteristic is transmitted from parent to offspring into a range of identifiable F₂ segregants. Disclaimer statement Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by the USDA, and does not imply its approval to the exclusion of other products that may also be suitable.     

Karyotype and C-banding inTrigonella sectionFoenumgraecum (Fabaceae)

The six species of the sectionFoenum-graecum ofTrigonella have the same chromosome number, 2n = 16.T. gladiata andT. cariensis have fairly symmetrical karyotypes, while those ofT. foenum-graecum, T. berythea, T. macrorrhyncha andT. cassia are asymmetrical. C-bands are present in all six species but the number of bands and their positive vary considerably among the species. The karyotype evidence suggests that none of the available species of theFoenum-graecum section can be considered as the wild progenitor of fenugreek.     

Synthesis and maturation of cross-reactive glycoprotein in fibroblasts deficient in arylsulfatase a activity

The biosynthesis of arylsulfatase A was studied in cultured fibroblasts by pulse-chase labeling with [2-³H]mannose; the enzyme was isolated by immunoprecipitation and denaturing polyacrylamide gel electrophoresis. In normal fibroblasts, and in fibroblasts from a patient with multiple sulfatase deficiency, the enzyme was synthesized as a glycoprotein of apparent molecular weight of 59,000; half of it was processed over a period of 4 days to M_r= 57,000. The precursor chain of M_r= 59,000 was secreted in the presence of 10 mM NH₄Cl. An immunoprecipitable glycoprotein of normal size was synthesized by fibroblasts from two unrelated patients with metachromatic leukodystrophy, but this material disappeared within twenty hours. In fibroblasts from an individual with pseudodeficiency of arylsulfatase A, the immunoprecipitable precursor glycoprotein was smaller (M_r= 56,000). The synthesis of cross-reactive proteins with altered properties supports the concept of allelic mutations as the genetic basis of metachromatic leukodystrophy and of arylsulfatase A pseudodeficiency.     

Neutrophil-associated lung injury after the infusion of activated plasma

Previous studies from our laboratory have shown that the infusion of zymosan-activated plasma (ZAP) caused large numbers of neutrophils (PMN) to accumulate in the lung. Although PMN are known to be activated by ZAP, it is unclear whether PMN delayed in the lung by ZAP infusion actually cause lung injury. The present study was designed to examine this question by measuring airway epithelial and endothelial injury. Airway epithelial injury was determined by depositing a known dose of fluorescein isothiocyanate-labeled dextran in the lung and measuring its appearance in the blood, and endothelial injury was measured by injecting colloidal carbon and measuring its accumulation in the microvasculature of the lung. The data show that ZAP infusion caused a mild epithelial and endothelial injury that did not increase either extravascular water or protein. This injury could be prevented either by depleting the animals of PMN or by pretreating them with indomethacin. In addition, the effect of ZAP infusion could be partially restored by transfusing donor PMN into the PMN-depleted animals. We conclude that ZAP infusion produces a mild lung injury that is dependent on PMN and the products of the cyclooxygenase pathway of arachidonic acid metabolism.     

Monocyte kinetics in rabbits

Previous studies of monocytes isolated from peripheral blood have suggested that the lung sequesters these cells and has an important role in monocyte kinetics. However, the lung also provides the first capillary bed encountered by these cells after intravenous injection. A major criticism of the previous reports is that the behavior of monocytes in the lung may be altered as a result of the isolation procedure. The present study addresses this question by comparing the distribution of isolated monocytes (87% pure) in various organs 10 min after they were injected into either the central venous or the arterial circulation. The data show that the extraction of monocytes on the first passage through the lung after intravenous injection was 86.5 +/- 1.5%. After the monocytes had circulated for 10 min, the lungs contained 35.5 +/- 2.5% of the cells after intravenous injection and 29.7 +/- 2.2% after intra-arterial injection (P greater than 0.05). The lung-to-blood recovery ratio after either intravenous or intra-arterial injection showed that the lung contained a marginating pool of monocytes that was five to seven times the size of the circulating pool. The retention of monocytes in a region of the lung was proportional to the regional erythrocyte transit time. The half-life of the radiolabeled monocytes in the circulation was approximately 25 h. We conclude that the lung contains a marginating pool of monocytes and speculate that they concentrate there in preparation for migration into the interstitium and air space of the lung.     

Ancient dominance of the Quercus calliprinos - Pistacia palaestina association in mediterranean Israel

Abstract. The natural Mediterranean maquis and forest vegetation of Israel is commonly considered to be composed mainly of four, roughly equal components: Pinus halepensis, deciduous oak, evergreen oak, and Ceratonia - Pistacia communities. They represent the past climax and subclimax of this region. Evidence accumulated from pollen analysis and wood remnant research in geological and archaeological excavations, as well as from written historical sources, shows that this view is wrong: the ancient vegetation in this area was dominated by Quercus calliprinos.     

Retinoic acid modulates the pattern of cell division in embryos ofLymnaea stagnalis (Mollusca)

All-trans retinoic acid is well known as a modulator of positional specification in vertebrate development. A similar mechanism may operate in molluscan development. Molluscan development is characterized by an invariant pattern of cell divisions, which allows the study of individual cells in the developing organism. Low concentrations of exogenous retinoic acid applied during gastrulation affect the cell division pattern in the early larval stage of the molluscLymnaea stagnalis. A few cells from the apical plate, a larval organ consisting of seven large cleavage-arrested cells, were induced by retinoic acid to resume cell division. They typically formed an area of proliferating small cells that resembles the adjacent areas of precursor cells of adult ectoderm. The identification of individual cells that are transformed by retinoic acid may provide new insights into the mechanisms underlying positional specification within the embryo.     

Lentil domestication: On the quality of evidence and arguments

The current views on lentil domestication are based on biological attributes of the wild progenitorLens culinaris ssp. orientalis and on assumptions which have never been tested. Seed dormancy, a major factor in the adaptation of ssp.orientalis to its natural habitat, makes it inappropriate for cultivation, because poor germination causes seed yield following cultivation to be equal to the amount of sown seeds. Higher yield, resulting from the evolution of a non-dormant type can be obtained only after five or six cycles of unprofitable cultivation. It is doubtful that incipient farmers would have undertaken such an endeavor without preexisting knowledge that non-dormant types could eventually be obtained. Experiments involving the sowing of wild lentil would have been much more successful if the non-dormant types were present in appreciable quantities in the seed stock. Establishment of that type in the natural population would have required a period of seven to eight years with favorable growing conditions allowing the non-dormant type to become widespread in the population, followed by massive predation by man reducing the hazard of a population explosion. The close similarity between isozyme profiles of the cultivated lentil and its wild progenitor indicates that lentil cultivation was attempted with seeds derived from different populations and in different areas.     

Crystallization and preliminary X-ray analysis of nonglycosylated tissue inhibitor of metalloproteinases-1, N30QN78Q TIMP-1

A nonglycosylated (N₃₀QN₇₈Q) form of the human tissue inhibitor of metalloproteinases, TIMP-1, has been prepared and crystallized in a form suitable for X-ray diffraction analysis. Small single crystals have been grown using sodium tartrate as a precipitant. The crystals are in space group P2₁, with cell dimensions a = 35.28, b = 53.95, c = 48.56, and β = 96.0°. There is a single molecule of TIMP-1 in the asymmetric unit. The crystals diffract to at least 2.3 Å resolution. Complete data have been collected to 2.9 Å and a search for heavymetal derivatives is in progress. © 1993 Wiley-Liss, Inc.