Replication of Deoxyribonucleic Acid and Crossing Over in Coprinus

Influence of activated A and B mating-type pathways on developmental processes in the basidiomycete Coprinus cinereus

“…Further studies of chromosome behaviour in basidia at this stage are needed to support these indirect arguments for B control of karyogamy and meiosis. In any case, it is intriguing that at the main checkpoint for the conversion of fruitbody primordia to into mature fruiting bodies, namely karyogamy, environmental factors such as light (Lu 1974) and nitrogen (Lu 1982) once again come into play and possibly together with the products of the B mating type genes. Whether also the A mating type genes play a role at the onset of fruiting body maturation remains unclear, since we currently have no possibility to test the effects of B genes on fruiting body maturation without simultaneously activating the A mating type pathway.…”

How do Agaricomycetes shape their fruiting bodies? 1. Morphological aspects of development

“…70e75 % of all basidia will be always in the same developmental phase, with the cells at the lower gill margin and at the edge closer to the stipe being always most advanced in development. As previously the gill formation, also basidia maturation within the gills moves along two gradients, outwards away from the stipe and upwards to the apex of the cap (Raju and Lu, 1970;Lu, 1982;Hammad et al, 1993a;Navarro-Gonz alez, 2008). Karyogamy within the basidia will complete over the whole gill surface after about 6 h (P5 þ 6 h).…”

“…The light signal possibly targets at premeiotic S-phase replication. It takes about 2 h to initiate in all probasidia the replication and 8 h to complete the S-phase (Lu, 1974b(Lu, , 1982(Lu, , 2000Lu and Jeng, 1975). Onset of nuclear fusion (stage karyogamy as defined in the sense of Lu, i.e.…”

“…that 5 % of all basidia entered the process; Raju and Lu, 1970;Lu, 1974bLu, , 2000 happens at the following morning in the P5 primordium (P5, 5e7 mm in size; Fig. 3A,J; corresponding to Lu's day 3 primordia and to the interims phase between Rosin's and Moore's prokaryogamic stage 1 and meiotic stage 2 primordia; Lu, 1974aLu, , 1982Lu, , 2000; Rosin and Moore, 1985a; K€ ues, 2000; Navarro-Gonz alez, 2008). Except for the cystidia and cystesia, virtually all cells in the hymenia of P5 structures (Fig.…”

“…Karyogamy within the basidia will complete over the whole gill surface after about 6 h (P5 þ 6 h). Meiosis directly follows karyogamy and takes about 8e9 h for all steps, to finish towards the end of the light phase (P5 þ 11 h; Kimaru and Takemaru, 1955;Raju and Lu, 1970;Lu, 1982Lu, , 2000Hammad et al, 1993a;Celerin et al 2000;Navarro-Gonz alez, 2008;. First sterigmata emerge 8 h after onset of karyogamy.…”