Characterization of Ctr family genes and the elucidation of their role in the life cycle of Neurospora crassa

• Published in: Fungal genetics and biology 2010-03, Vol.47 (3), p.237-245
• Main Authors: Korripally, Premsagar, Tiwari, Anand, Haritha, Adhikarla, Kiranmayi, Patnala, Bhanoori, Manjula
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Cation Transport Proteins - genetics; Cation Transport Proteins - metabolism; Cation Transport Proteins - physiology; Cloning, Molecular; Complementation; conidia; Conidial germination; copper; Ctr family; Developmental phases; DNA, Fungal - metabolism; Fungal Proteins - genetics; Fungal Proteins - metabolism; Fungal Proteins - physiology; gene expression; Gene Expression Profiling; Gene Expression Regulation, Fungal; Genes, Mating Type, Fungal; Genetic Complementation Test; Genome, Fungal; Life cycle; Membrane Proteins - genetics; Membrane Proteins - metabolism; messenger RNA; metal ions; Metal transporters; metals; N. crassa; Neurospora crassa; Neurospora crassa - genetics; Neurospora crassa - growth & development; Neurospora crassa - metabolism; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Promoter Regions, Genetic; Protein Kinases - genetics; Protein Kinases - metabolism; Repressor Proteins - genetics; Repressor Proteins - metabolism; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - genetics; Sequence Alignment; spore germination; Spores, Fungal - genetics; Spores, Fungal - metabolism; tcu-1; tcu-1 gene; tcu-2; tcu-2 gene; tcu-3; tcu-3 gene; transporters
• ISSN: 1087-1845; 1096-0937
• DOI: 10.1016/j.fgb.2009.12.006

Transcriptional analysis using qRT-PCR of 62 metal ion transporters during conidial germination of Neurospora crassa showed a significant up regulation of a hypothetical copper transporter gene, tcu-1, that belongs to the Ctr family. Herein we characterised the Ctr family genes ( tcu- 1, tcu- 2 and tcu- 3) and deciphered their role in various developmental phases of the N. crassa life cycle. Cross complementation assays in copper uptake mutant of Saccharomyces cerevisiae revealed that tcu-1, tcu-2 and tcu-3 are functional homologs of S. cerevisiae copper transporters. Expression studies of Ctr family members in various developmental phases of N. crassa showed differential expression pattern for high-affinity copper transporter, TCU1. Functional analysis of their gene knockout mutants showed that tcu- 1 is essential for saprophytic conidial germination, vegetative growth and perithecia development under copper limited conditions while conidiation remained unaffected.