Regulation of Cyclic AMP Metabolism by the Incompatibility Factors in Coprinus cinereus

Abstract

Adenylate cyclase and phosphodiesterase activities were assayed during the course of sexual reproduction in Coprinus cinereus. High levels of adenylate cyclase activity and low levels of phosphodiesterase activity were found in all dikaryons, in Amut Bmut strains, and in the monokaryotic fruiter Fist. Corresponding to this, a high level of cAMP was found in these strains. On the other hand, low levels of cAMP were found in semi-compatible heterokaryons (common-A and common-B), and in Amut and Bmut strains, where the events leading to sexual morphogenesis had been switched on only partially. CAMP-binding and CAMP-dependent protein kinase activities were detected in the dikaryons, and in Amut Bmut and Fist strains, but were negligible in the sexually sterile strains. The results indicated that both A and B factors are involved in the coordinate regulation of adenylate cyclase, phosphodiesterase, and CAMPdependent protein kinase during fruit body formation. ~ ~ Abbreviation : 8-N,-[3H]cAMP, 8-azidoadenosine 3',5'-[3H]monophosphate. 0001-2723 0 1985 SGM

Blue Light Overrides Repression of Asexual Sporulation by Mating Type Genes in the BasidiomyceteCoprinus cinereus

“…With the repression of oidiation in dikaryons we have found an example in which both mating type loci control the expression of the very same property. A and B also coordinately regulate cAMP repression which, incidentally, is induced by light in dikaryons and in the homokaryon AmutBmut but not in monokaryons or Amut B or A Bmut homokaryons (Uno et al, 1974;Swamy et al, 1985b). Blue light is required for fruit body induction and maturation in C. cinereus (Tsusué , 1969;Lu, 1974a;Morimoto and Oda, 1974;Kamada et al, 1978), high levels of cAMP correlate with fruiting ability, and cAMP is capable even of triggering fruiting in a particular monokaryotic mutant of C. cinereus (Uno and Ishikawa, 1971, 1982.…”

“…Whether cAMP plays a direct or an indirect role in modification of A reactions has to be elucidated. cAMP-dependent, light-induced, and A and B mating type controlled protein phosphorylation have been demonstrated in C. cinereus (Uno and Ishikawa, 1982;Swamy et al, 1985b) and potential phosphorylation sites for cAMP-dependent protein kinases were observed within an essential conserved domain of the HD1 proteins Gieser and May, 1994;Kü es et al, 1994a;Asante-Owusu et al, 1996).…”

Life History and Developmental Processes in the BasidiomyceteCoprinus cinereus

“…Although A and B mating-type genes regulate distinct cellular functions (see above), in the dikaryon they coordinately control functions such as cyclic AMP (cAMP) production, cAMP-dependent protein kinase activity (453,454), repression of oidiation (232), and, as suggested previously for Amut Bmut homokaryons (265,452) and now shown in A and B activated transformants, also fruiting-body initiation (240a). Strikingly, all these functions are also light regulated (203,232,277,350,351,492).…”

“…There are, however, considerable differences in the way these factors are linked in regulation. For cAMP production and cAMP-dependent protein kinase activity, both mating-type pathways have to be active and light has a stimulatory effect (453,454,492). In fruiting-body initiation, where light is usually required (350, 351) (see above), activation of the A pathway can be sufficient (258,261,459) but additional activation of the B mating-type pathway clearly promotes fruiting when light signals are provided (240a, 459; Kües, unpublished).…”

Influence of light on the morphological changes that take place during the development of the Flammulina velutipes fruit body

“…With regard to the molecular mechanisms involved in these light-regulated events, the formation of the fruit body of S. commune is known to involve the expression of several genes (Wessels et al 1987;Ruiters et al 1988). In addition, the levels of cyclic adenosine monophosphate (cAMP), which is known as a fruiting stimulating factor (Uno and Ishikawa 1973;Swamy et al 1985), increase after light irradiation (YliMattila 1987). Thus, light is one of the most important factors that regulate fruit body formation in basidiomycetous mushrooms.…”