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Three α-tubulin isoforms were previously detected in Neurospora crassa. We have cloned and analysed two α-tubulin cDNAs, Tub αA and Tub αB that encode polypeptides of 453 and 451 amino acids, respectively. The encoded amino acids exhibit an unusual divergence of 35%. This is the highest divergence ever observed between α-tubulins from the same species. The expression of the two genes is developmentally regulated. We did not detect any transcription of the Tub αA gene in dormant macroconidia and during the first 30 min of development even though the α-tub A protein is already present in the early stage of germination. In contrast, the Tub αB gene is continuously transcribed during the vegetative cycle and the expression profile of the protein follows the ones of its mRNA

Highly specific polyclonal antibodies against actin from Allomyces arbuscula were produced in rabbits, immunopurified by immunoblotting and specified with actin isolated from Neurospora crassa and mouse skeletal muscle. Used as immunofluorescence probes, they allowed localization of actin in the sequential gametophytic stages of the mould.

Opposite morphogenetic changes have been provoked by growing A. arbuscula in the presence of two antimicrotubular agents: taxol maintained vegetative hyphal elongation growth and thereby prevented their apical differentiation into couples of male-female gametangia; nocodazole prevented germ tube outgrowth, induced emergence of epihyphal rhizoids and led to altered positioning of intrahyphal nuclei. Primary hyphal growth in the presence of taxol prevented the nocodazole-induced morphogenetic disturbance.

According to our model of pregenetic molecular coding, nucleobase doublets anticodons were, by stereochemical affinities, the primary codons for amino acid letters of the primitive peptide sequences. Such doublets, anticipating the base sequences of the «modern» triplet codons of the reading strand of DNA would have been initially stabilized along polyphosphate chains by phosphoamidic dehydrating condensation with tripolyphosphate into riboseless prenucleic acids.

Les molécules d'un simple et monomérique cyclo-tétrapeptide, dissoutes dans une solution saline anhydrisante riche en Mg²⁺, ne sont pas seulement stabilisées mais peuvent aussi agir comme des moules pour leur replication autocatalytique ainsi que démontré par une augmentation significative des ponts dipeptidiques à partir et seulement de ses amino acides homologues.

Un modèle d'évolution prébiotique de molécules codantes reposant sur l'interaction de leurs liaisons faibles et fortes peut relier (1) le code originel à 1 lettre d'acides aminés liés par covalence en (cyclo)peptides, par (2) sa relève par code prénucléique à doublets de 2 lettres de bases associées par liaisons polyphospho (P)-amidiques (N), au (3) code moderne à 3 lettres par triplets de nucléotides, singularisé par l'insertion médiane du ribose (P-r-N) à la relève par l'ARN.

Les grosses colonies de Parmelia caperata sur troncs de chênes au Bois des Mouilles (Genève) sont atteintes d'une nécrose centrale et d'un jaunissement périphérique précédant leur blanchiment final en zone proximale de l'autoroute de contournement.

Intermolecular H bonding is bioevolutionarily motive by (1) promoting prototypic self-assembly of H₂O molecules, and (2) providing template forces for stacking cyclic peptides into prevital proproteinaceous nanotubes possibly endowed with self-reproductive competence.

Incompletely disjuncted male gametangia only may be formed in the presence of the antiactin cytochalasin E while either bisexual couples or undifferentiated hyphae are formed in the presence of the antitubulin agents benomyl and nocodazole. F-actin must be polarly directed to the normally differentiating female gametangium.

Fluorescent probing with chlorotetracycline of outgrowing and elongating germ tubes from Neurospora crassa conidia revealed a maximal fluorescence and therefore sequestration of Ca²⁺ ions in their subapical mitochondria.