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1Latest Papers from Table of Contents or Articles in PressJ. A. Banks ; T. Nishiyama ; M. Hasebe ; J. L. Bowman ; M. Gribskov ; C. dePamphilis ; V. A. Albert ; N. Aono ; T. Aoyama ; B. A. Ambrose ; N. W. Ashton ; M. J. Axtell ; E. Barker ; M. S. Barker ; J. L. Bennetzen ; N. D. Bonawitz ; C. Chapple ; C. Cheng ; L. G. Correa ; M. Dacre ; J. DeBarry ; I. Dreyer ; M. Elias ; E. M. Engstrom ; M. Estelle ; L. Feng ; C. Finet ; S. K. Floyd ; W. B. Frommer ; T. Fujita ; L. Gramzow ; M. Gutensohn ; J. Harholt ; M. Hattori ; A. Heyl ; T. Hirai ; Y. Hiwatashi ; M. Ishikawa ; M. Iwata ; K. G. Karol ; B. Koehler ; U. Kolukisaoglu ; M. Kubo ; T. Kurata ; S. Lalonde ; K. Li ; Y. Li ; A. Litt ; E. Lyons ; G. Manning ; T. Maruyama ; T. P. Michael ; K. Mikami ; S. Miyazaki ; S. Morinaga ; T. Murata ; B. Mueller-Roeber ; D. R. Nelson ; M. Obara ; Y. Oguri ; R. G. Olmstead ; N. Onodera ; B. L. Petersen ; B. Pils ; M. Prigge ; S. A. Rensing ; D. M. Riano-Pachon ; A. W. Roberts ; Y. Sato ; H. V. Scheller ; B. Schulz ; C. Schulz ; E. V. Shakirov ; N. Shibagaki ; N. Shinohara ; D. E. Shippen ; I. Sorensen ; R. Sotooka ; N. Sugimoto ; M. Sugita ; N. Sumikawa ; M. Tanurdzic ; G. Theissen ; P. Ulvskov ; S. Wakazuki ; J. K. Weng ; W. W. Willats ; D. Wipf ; P. G. Wolf ; L. Yang ; A. D. Zimmer ; Q. Zhu ; T. Mitros ; U. Hellsten ; D. Loque ; R. Otillar ; A. Salamov ; J. Schmutz ; H. Shapiro ; E. Lindquist ; S. Lucas ; D. Rokhsar ; I. V. Grigoriev
American Association for the Advancement of Science (AAAS)
Published 2011Staff ViewPublication Date: 2011-05-10Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Angiosperms/chemistry/genetics ; *Biological Evolution ; Bryopsida/genetics ; Chlamydomonas/chemistry/genetics ; DNA Transposable Elements ; Evolution, Molecular ; Gene Expression Regulation, Plant ; Genes, Plant ; *Genome, Plant ; MicroRNAs/genetics ; Molecular Sequence Data ; Phylogeny ; Plant Proteins/genetics/metabolism ; Proteome/analysis ; RNA Editing ; RNA, Plant/genetics ; Repetitive Sequences, Nucleic Acid ; Selaginellaceae/*genetics/growth & development/metabolism ; Sequence Analysis, DNAPublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 1432-2048Keywords: Cytokinin ; Gametophore over-producing mutants ; PhyscomitrellaSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Several phenotypically distinct classes of gametophore overproducing mutants have been isolated in P. patens. Mutants belonging to one class resemble the wild-type strain grown on medium containing a high concentration (5–50μM) of exogenously supplied cytokinin. Mutants of this type can increase the production of gametophores in the wildtype strain by cross-feeding it through the culture medium. Mutants belonging to another class resemble the wild-type strain cultured on medium containing a lower concentration (50–500 nM) of exogenous cytokinin. Mutants of this kind cannot cross-feed the wild-type strain through the culture medium. A component, required by the wild-type strain for the initiation of gametophores in response to cytokinin, either is not formed or is not activated in the dark. Gametophore over-producing mutants may also be unable to synthesize/activate this component in the dark and thus, like the wild-type strain, they produce no gametophores in the dark.Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 1432-2048Keywords: Auxin ; Cytokinin ; Mutants ; Physcomitrella ; Protoplast fusionSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Mutants altered in their response to auxins and cytokinins have been isolated in the moss Physcomitrella patens either by screening clones from mutagenized spores for growth on high concentrations of cytokinin or auxin, in which case mutants showing altered sensitivities can be recognized 3–4 weeks later, or by non-selective isolation of morphologically abnormal mutants, some of which are found to have altered sensitivities. Most of the mutants obtained selectively are also morphologically abnormal. The mutants are heterogeneous in their responses to auxin and cytokinin, and the behaviour of some is consistent with their being unable to make auxin, while that of others may be due to their being unable to synthesize cytokinin. Physiological analysis of the mutants has shown that both endogenous auxin and cytokinin are likely to play important and interdependent roles in several steps of gametophytic development. Although their morphological abnormalities lead to sterility, genetic analysis of some of the mutants has been possible by polyethyleneglycol induced protoplast fusion.Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesStaff View
ISSN: 1617-4623Source: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Summary A technique has been developed for the isolation of large numbers of protoplasts from protonemal tissue of Physcomitrella patens, and for their regeneration to give whole plants. Somatic hybrids have been selected following treatment of mixtures of protoplasts from complementary auxotrophic strains with 50 mM CaCl2 at high pH. The hybrids have a morphology different from that of normal haploid strains, but similar to that of aposporously produced diploids. The progeny resulting from selffertilisation of the hybrids show a segregation which is consistent with their being the products of meioses in an autotetraploid.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesStaff View
ISSN: 1617-4623Source: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Summary Fusion of protoplasts from the moss, Physcomitrella patens, was induced using polyethyleneglycol. Protoplasts were isolated from six nicotinic acid auxotrophic strains of independent origin and fusion was induced in all possible pairwise combinations. Complementation was detected by the ability to recover hybrids able to grow without nicotinic acid supplement. On the basis of the results presented, three nonoverlapping complementation groups were identified.Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 1617-4623Source: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Summary Eighteen nutritional mutants have been isolated in the haploid, monoecious moss, Physcomitrella patens: five nicotinic acid auxotrophs, four p-aminobenzoic acid auxotrophs, four adenine auxotrophs, two amino acid requiring mutants and three nitrate non-utilising mutants. Seventeen of them were obtained using total isolation; one was isolated selectively. Strains resistant to the amino acid analogues, D-serine and p-fluorophenyl-alanine, and the purine analogue, 8-azaguanine, have been selected. Many of the auxotrophs are self-sterile. Crosses between auxotrophic strains have been effected and the progeny analysed. No linkage has been detected. Nicotinic acid auxotrophy has resulted from mutation in at least two genes. Self-sterility segregates as a pleiotropic effect of four mutations which produce nutritional dependence. A diploid strain has been obtained by aposporus regeneration from a hybrid sporophyte and the phenotypes of progeny resulting from the self-fertilisation of this strain have been analysed.Type of Medium: Electronic ResourceURL: