Quantification of Cyclobutane Pyrimidine Dimers Induced by UVB Radiation in Conidia of the Fungi Aspergillus fumigatus, Aspergillus nidulans, Metarhizium acridum and Metarhizium robertsii

Autor(es)

Nascimento, Erika ^[1] ; da Silva, Sergio H. ^[1] ; Marques, Everaldo dos Reis ^[1] ; Roberts, Donald W. ^[2] ; Braga, Gilberto U. L. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Analises Clin Toxicol & Bromatol, Fac Ciencias Farmaceut Ribeirao Preto, BR-14049 Ribeirao Preto, SP - Brazil

^[2] Utah State Univ, Dept Biol, Logan, UT 84322 - USA

• Tipo de documento: Artigo Científico
• Fonte: Photochemistry and Photobiology; v. 86, n. 6, p. 1259-1266, NOV-DEC 2010.
• Citações Web of Science: 15

Resumo

Conidia are responsible for reproduction, dispersal, environmental persistence and host infection of many fungal species. One of the main environmental factors that can kill and/or damage conidia is solar UV radiation. Cyclobutane pyrimidine dimers (CPD) are the major DNA photoproducts induced by UVB. We examined the conidial germination kinetics and the occurrence of CPD in DNA of conidia exposed to different doses of UVB radiation. Conidia of Aspergillus fumigatus, Aspergillus nidulans and Metarhizium acridum were exposed to UVB doses of 0.9, 1.8, 3.6 and 5.4 kJ m-2. CPD were quantified using T4 endonuclease V and alkaline agarose gel electrophoresis. Most of the doses were sublethal for all three species. Exposures to UVB delayed conidial germination and the delays were directly related both to UVB doses and CPD frequencies. The frequencies of dimers also were linear and directly proportional to the UVB doses, but the CPD yields differed among species. We also evaluated the impact of conidial pigmentation on germination and CPD induction on Metarhizium robertsii. The frequency of dimers in an albino mutant was approximately 10 times higher than of its green wild-type parent strain after exposure to a sublethal dose (1.8 kJ m-2) of UVB radiation. (AU)

• Processo FAPESP: 03/07702-9 - Abordagens genômica e proteômica para a identificação de genes e de proteínas envolvidos na tolerância à radiação solar em fungos: aplicações para o desenvolvimento de fotossensibilizadores e para a obtenção de linhagens mais tolerantes à radiação UV
• Beneficiário: Gilberto Úbida Leite Braga
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores