The Neurospora crassa methyltransferase LAE-1: molecular function and interacting partners

• Grant number: 18/00355-7
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: April 01, 2018
• End date: June 29, 2018
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Gilberto Úbida Leite Braga
• Grantee: Guilherme Thomaz Pereira Brancini
• Supervisor: Luis Maria Corrochano Pelaez
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: Universidad de Sevilla (US), Spain
• Associated to the scholarship: 15/24305-0 - Evaluating the effects of blue and red light on the stress tolerance and the proteome of the entomopathogenic fungus Metarhizium acridum, BP.DR

Abstract

The putative methyltransferase LaeA is the master regulator of secondary metabolism in Aspergillus nidulans. Deletion of LaeA coding gene, laeA, results in decreased production of many secondary metabolites including the aflatoxin precursor sterigmatocystin. LaeA also interacts with the velvet protein VeA, a central regulator of development. VeA-LaeA interaction was found to be necessary for secondary metabolism. Also, by interacting with VeA and regulating the levels of VeA and other velvet proteins, LaeA plays a role in development. Cleistothecia, which are sexual fruiting bodies, are smaller and harbor fewer ascospores in laeA null mutants. This is attributed to the small number of nursing Hülle cells observed in these mutants. The transition from sexual to asexual development brought about by light exposure is absent in ”laeA strains, further showing that LaeA is an important developmental regulator. In this sense, understanding how laeA homologue genes function in different fungi could provide valuable knowledge on how evolutionarily conserved these genes and their functions are. In the model ascomycete Neurospora crassa, a homologue LaeA protein is predicted and is encoded by the lae-1 gene. However, a molecular characterization of lae-1/LAE-1 is not currently available. Therefore, the current research project is a proposal to characterize LAE-1 with respect to its interacting partners, to study lae-1 expression during development, and to analyze the phenotype of lae-1 null mutants in N. crassa.