摘要:

AbstractA total storage protein fraction was prepared from mustard (Sinapis albaL.) seeds via isolated protein bodies and characterized by sedimentation, immunological, and electrophoretic techniques. Mustard seed storage protein consists of three fractions (1) a “legumin‐like” 13‐S complex composed of two pairs of disulfide‐linked polypeptides (16.5 + 28.5 kDa and 19.5 + 34 kDa, respectively) and two single polypeptides (18 kDa and 26 kDa), (2) a “vicilin‐like” 9‐S complex composed of two glycoproteins (64 kDa and 77 kDa), and (3) two small polypeptides (10 kDa and 11 kDa) which probably represent the 1.7‐S complex found in otherCruciferae. In contrast to related species, no glycosylated polypeptide was found in the 13‐S complex. Immunological relationships were found between the paired polypeptides of the 13‐S complex but not between polypeptides of the 13‐S complex and polypeptides of the 9‐S complex. Pulse‐chase labeling andin vitrotranslation of polysomal RNA from young embryos demonstrated that the polypeptides of the 13‐S complex originate from high molecular mass precursors, except for the 18 kDa polypeptide which appears to be synthesized in its final size. The amino‐acid composition of the major polypeptides of the

ISSN:0932-8629    

DOI:10.1111/j.1438-8677.1988.tb00011.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractAuxin‐mediated elongation growth of isolated subapical coleoptile segments of maize (Zea maysL.) is controlled by the extensibility of the outer cell wall of the outer epidermis (Kutschera et al., 1987). Here we investigate the hypothesis that auxin controls the extensibility of this wall by changing the orientation of newly deposited microfibrils through a corresponding change in the orientation of cortical microtubules. On the basis of electron micrographs it is shown that cessation of growth after removal of the endogenous source of auxin is correlated with a relative increase of longitudinally orientated microfibrils and microtubules at the inner wall surface. Conversely, reinduction of growth by exogenous auxin is correlated with a relative increase of transversely orientated microfibrils and microtubules at the inner wall surface. These changes can be detected 30–60 min after the removal and addition of auxin, respectively. The functional significance of directional changes of newly desposited wall microfibrils for the control of elongation growth is discus

ISSN:0932-8629    

DOI:10.1111/j.1438-8677.1988.tb00012.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThe gene for the large subunit of ribulose bisphosphate carboxylase/oxygenase (rbcL) has been mapped on theOenothera hookeriplastid chromosome. It is located close to the gene for the herbicide‐binding “32 kd” protein of the photosystem II reaction center (psbA), at a position different from that found in the ancestral angiosperm type of plastid chromosomes, due to an inversion in the large single‐copy region. The gene codes for a polypeptide of 475 amino acid residues corresponding to a molecular mass of 52.7 kd. The deduced amino acid composition diverges by 4.8% from the amino acid sequence of the spinach protein and by 8.2% from that of maize. The corresponding nucleotide sequences differ by 8.5 % and 15 % from each other. The rbcL gene of the RuBPcase/oase‐deficientOenotheraplastome mutant sigma contains a TTAAC deletion at amino acid residues 270/271 which introduces a frame shift and an amber stop codon seven triplets later. This lesion which probably arose by slipped mispairing is consistent with the previously observed, virtually full‐length mRNA that is decoded into a truncated large subunit polypeptide of approximately 30 kdin vitr

ISSN:0932-8629    

DOI:10.1111/j.1438-8677.1988.tb00013.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractTemperature dependences of leaf water potentials (ψleaf) of frozen leaves of frosthardy ivy and winter barley were determined psychrometrically and found to coincide with the respective water potentials of ice which were obtained using the same technique. The water potentials of ice showed good agreement with theoretically established data. Analysis of the components of ψ of frozen leaves ofHedera helixrevealed ideal equilibrium freezing, i.e. the governing of the relative content of liquid (or frozen) water solely by the osmotic potential. In winter barley, by contrast, a negative pressure potential was demonstrated to contribute to ψleaf. even under conditions of moderate frost. This reduced the degree of protoplast dehydration and the extent to which the concentrations of the cellular solutes rose. Such a freezing behavior is termed non‐ideal equilibrium freezing. Depending on the original content of leaf water, the volume increments of liquid water due to the negative pressure potential amounted up to 10% at −6 °C and even more at a lower temperature. In addition to the experimental data, a theoretical treatment of psychrometry at subzero temperatures is pr

ISSN:0932-8629    

DOI:10.1111/j.1438-8677.1988.tb00014.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractBased on corresponding ascocarp ontogeny and thallus structure, the generaEuopsisandHarpidiumare included in the family Lichinaceae. In the two species ofEuopsis, E. granatinaandE. pulvinata, the apothecia develop from ascogonia in generative tissue, while inH. rutilansthey are pycnoascocarps. In thallus anatomy, the species ofEuopsisresemblePyrenopsis haematopsisand allied species, whileH. rutilanscorresponds in structure and development of the thallus and apothecia toPyrenopsis haemaleella(syn.P. sphinctotricha).H. rutilansis the first member of Lichinaceae known to have only a green algal symbiont. InE. granatina, two phycobionts are always present, a species ofGloeocapsaand a chlorococcalean alga.InEuopsisandHarpidium, the ascus wall is composed of an outer, non‐expansible and an inner, expansible layer; the latter surrounds the protoplast as an amyloid collar, which expands during spore release into a long, tapering rostrum. InEuopsis, the outer wall layer is strongly amyloid and the upper part separated from the expanded amyloid rostrum by a non‐amyloid zone, appearing like a slit in LM studies. The ultrastructure and function of the ascus inE. granatinahas been studied in TEM and is interpreted as functionally unitunicate‐rostrate. Unitunicate asci with short rostrum are described forP. haemaleellaandP. haemat

ISSN:0932-8629    

DOI:10.1111/j.1438-8677.1988.tb00015.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY