Patterns of polypeptide synthesis in various maize organs under anaerobiosis

The pattern of protein synthesis was compared in several organs of maize (Zea mays L.) under aerobic and anaerobic conditions. Protein synthesis was measured by [³⁵S]methionine incorporation and analysis by two-dimensional native-SDS (sodium lauryl sulfate) polyacrylamide gel electrophoresis and fluorography. The aerobic protein-synthesis profiles were very different for root, endosperm, scutellum and anther wall. However, except for some characteristic qualitative and quantitative differences, the patterns of protein synthesis during anaerobiosis were remarkably similar for these diverse organs and also for mesocotyl and coleoptile. The proteins synthesized were the anaerobic polypeptides (ANPs) which have been previously described in anaerobic roots of seedlings. Leaves exhibited no detectable protein synthesis under anaerobic conditions, and died after a short anaerobic treatment. Evidence is presented that the ANPs are not a generalized response to stress. This indicates that the ANPs are synthesized as a specific response to anaerobic conditions such as flooding.Abbreviations ADH alcohol dehydrogenase - ANP anaerobic polypeptide - SDS sodium lauryl sulfate     

Genes Affecting the Expression of Cytochrome c in Yeast: Genetic Mapping and Genetic Interactions

The four mutant genes, cyc2, cyc3, cyc8 and cyc9, that affect the levels of the two iso-cytochromes c in the yeast Saccharomyces cerevisiae have been characterized and mapped. Both cyc2 and cyc3 lower the amount of iso-1-cytochrome c and iso-2-cytochrome c; whereas, cyc8 and cyc9 increase the amount of iso-2-cytochrome c. The cyc2, cyc3, cyc8 and cyc9 genes are located, respectively, on chromosomes XV, I, II and III, and are, therefore, unlinked to each other and unlinked to CYC1, the structural gene of iso-1-cytochrome c and to CYC7, the structural gene of iso-2-cytochrome c. While some cyc3 mutants are completely or almost completely deficient in cyotchromes c, none of the cyc2 mutants contained less than 10% of parental level of cytochrome c even though over one-half of the mutants contain UAA or UAG nonsense mutations. Thus, it appears as if a complete block of the cyc2 gene product still allows the formation of a residual fraction of cytochrome c. The cyc2 and cyc3 mutant genes cause deficiencies even in the presence of CYC7, cyc8 and cyc9, which normally cause overproduction of iso-2-cytochrome c. We suggest that cyc2 and cyc3 may be involved with the regulation or maturation of the iso-cytochromes c. In addition to having high levels of iso-2-cytochromes c, the cyc8 and cyc9 mutants are associated with flocculent cells and other abnormal phenotypes. The cyc9 mutant was shown to be allelic with the tup1 mutant and to share its properties, which include the ability to utilize exogenous dTMP, a characteristic flocculent morphology, the lack of sporulation of homozygous diploids and low frequency of mating and abnormally shaped cells of alpha strains. The diverse abnormalities suggest that cyc8 and cyc9 are not simple regulatory mutants controlling iso-2-cytochrome c.     

Sesquiterpene lactones and systematics of the genus Artemisia

The sesquiterpene lactones isolated from species in the genus Artemisia have been reviewed in an attempt to better understand the phylogeny and systematics of the four sections (subgenera), Abrotanum, Absinthium, Dracunculus and Seriphidium, proposed by Besser in 1829. The absence of hair on the receptacle is the only morphological characteristic separating species of Abrotanum from the species of Absinthium. There are no chemical characteristics segregating the species in these two subgenera since both produce eudesmanolides and guaianolides that are identical or biosynthetically similar. This suggests that the two subgenera could be combined into one (Artemisia) as proposed by Poljakov. The subgenus Seriphidium is composed of two geographical groups, one in the Old World and the other in the New World. The Old World species almost exclusively produce sesquiterpene lactones in the eudesmanolide class whereas the New World species (section Tridentatae) produce eudesmanolides and guaianolides, many of the latter being identical or structurally related to the sesquiterpene lactones in New World Abrotanum species. The chemical data in conjunction with geographic distributions suggest that the subgenus Seriphidium is polyphyletic and that the section Tridentatae originated from Abrotanum. Consequently, the Tridentate should be recognized as a subgenus separate and distinct from the Old World Seriphidium. There was insufficient information from the subgenus Dracunculus for interpretation.     

Development of the bovine acrosome

Summary In the present study the development of the bovine acrosome was investigated using conventional electron-microscopical techniques as well as the phosphotungstic-acid (PTA) technique (Rambourg 1967) including enzymatic digestion experiments. As in other species and in accordance with previous light-microscopical studies (Clermont and Leblond 1955) four phases of acrosomal differentiation can be discerned: the Golgi-phase, cap-phase, acrosome-phase, and maturation-phase.In the bull no internal pattern of the acrosomal content can be observed, either with conventional uranyl acetate-lead citrate staining or with the PTA-techniques. Our results support the observation in other species (Fawcett et al. 1971) that no intrinsic polymerization or crystallization process of the acrosomal content is responsible for acrosomal shaping. Some of our results suggest the influence of external forces on acrosomal development in the bull. During the cap-phase and the acrosome-phase accumulations of smooth endoplasmic reticulum and a layer of fine filaments can be observed in the Sertoli-cell cytoplasm, immediately adjacent to the developing acrosome. A temporary influence of these structures on acrosomal development seems possible. The PTA-positive staining of the developing bovine acrosome is probably due to the presence of acrosomal glycoproteins; however, our results do not exclude the possibility that molecules other than glycoproteins contribute to the positive PTA-staining of the developing acrosome.Supported by a grant from the Deutsche Forschungsgemeinschaft     

Down and Turner syndromes in a female infant with 47,X,del(X)(p11),+21

Summary This report describes a female infant with a 47,X,del(X)(p11),+21 karyotype who has clinical features of both Down and Turner syndromes. The majority of her clinical features are suggestive of Down syndrome.     

Epididymal sarcoidosis: a report of two cases and a review of the literature

Two cases of epididymal sarcoidosis, presenting as scrotal masses, are described. Biopsies of the epididymis and scalene nodes established the diagnosis. The literature of epididymal sarcoid and its differential diagnosis is discussed.     

Chemical induction of β-carotene biosynthesis

Marsh white seedless grapefruit were treated with the 2-diethylaminoethanol esters of the following acids: benzoic, phenylacetic, hydrocinnamic, 4-phenylbutyric, 5-phenylvaleric, valeric, hexanoic, heptanoic, octanoic, nonanoic, 5-chlorovaleric, cyclohexanecarboxylic, phenoxyacetic, p-chlorophenoxyacetic, 3-phenoxypropionic, cinnamic and p-chlorocinnamic. Several of these esters, in particular the hexanoate, 4-phenylbutyrate and cinnamate, caused the accumulation of large amounts of β-carotene. The effects of the hexanoate and of 2-phenoxytriethylamine, which causes only lycopene accumulation, were studied as functions of time. The hexanoate caused the rapid accumulation of lycopene during the first day. The amount of lycopene then began to decrease and that of β-carotene increased until, after 14 days, β-carotene was the major pigment. 2-Phenoxytriethylamine caused rapid lycopene accumulation during the first day and a slow steady increase afterwards. Thus, the mode of action of the β-carotene inducers may be similar to that of the lycopene inducers except that the former are probably rapidly hydrolysed by the esterase(s) in the flavedo, so that they no longer inhibit the cyclase(s), and β-carotene is accumulated at the expanse of lycopene.