Regulation by light of conidiation genes in Aspergillus nidulans

C Ruger-Herreros*, M Olmedo, R Fernández-Barranco, LM Corrochano, D Cánovas

Author address: 

Depto de Genetica, Avenida Reina Mercedes,6 Universidad de Sevilla, Spain

Abstract: 

The ascomycete fungus Aspergillus nidulans is a model organism for the research on conidiation. Red and blue light stimulate conidiation in A. nidulans, but mutations in the veA gene allow conidiation in the dark. Conidiation in A. nidulans is controlled by a master regulator, the product of the brlA gene. M any gene products act upstream of brlA, presumably allowing the synthesis of chemicals or allowing the transduction of environmental signals, to trigger brlA transcription and conidiation. The regulation of conidation by light may occur through activation of the expression of some regulatory genes. W e have shown that the expression of several conidiation genes, including brlA, fluG flbA, flbB and flbC, is activated by light. The level of photoinduction was moderate, between 4-10 fold, and changed with the age of the culture and the genetic background. Some genes, like brlA, are activated by light regardless of age, but flbA was only induced by light in 18 h-mycelia, while flbC was only induced in 25 h-mycelia. Mutation in veA did not prevent photoactivation of gene expression, and an increase in light-dependent mRNA accumulation was observed for flbA and flbC. The veA mutant did show an increase in the accumulation of some conidiation mRNAs in the dark. The activation by light of conidiation genes would provide increased amounts of regulatory proteins for conidiation clarifying the role of light on conidation. *Student poster
2009

abstract No: 

40

Full conference title: 

6th International Aspergillus Meeting
    • Asperfest 6 (2009)