Isolation of differentially expressed cDNA clones from salt adapted Aspergillus nidulans

• Published in: Current genetics 1996, Vol.29 (2), p.130-135
• Main Authors: Redkar, R.J, Lemke, P.A, Singh, N.K. (Auburn Univ. (USA). Dept. of Botany and Microbiology)
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphatases - chemistry; Adenosine Triphosphatases - genetics; ADN; Amino Acid Sequence; ASPERGILLUS NIDULANS; Aspergillus nidulans - genetics; Aspergillus nidulans - physiology; CLONACION MOLECULAR; CLONAGE MOLECULAIRE; Cloning, Molecular; DNA, Complementary - chemistry; DNA, Complementary - genetics; DNA, Complementary - isolation & purification; DNA, Mitochondrial - chemistry; DNA, Mitochondrial - genetics; ESTRES; EXPRESION GENICA; EXPRESSION DES GENES; Fungal Proteins - biosynthesis; Fungal Proteins - genetics; Gene Expression Regulation, Fungal; Molecular Sequence Data; Ribosomal Proteins - chemistry; Ribosomal Proteins - genetics; SALES; Salts - pharmacology; SEL; Sequence Homology, Amino Acid; STRESS; TOLERANCE AU SEL; TOLERANCIA A LA SAL
• ISSN: 0172-8083; 1432-0983
• DOI: 10.1007/BF02221576

Differentially expressed cDNA clones were isolated from salt-adapted Aspergillus nidulans (FGSC +359). Poly (A)+ RNA from adapted mycelia was used to construct a lambda Uni-ZAP cDNA library. The library was screened with mixed subtracted cDNA probes. Three hundred and fifty-seven positive plaques were isolated in the primary screening. Sixty-two randomly selected plaques were purified and placed into eight different cross-hybridization groups. A representative cDNA from each group was used to study expression under unadapted, salt-adapted and salt-shock conditions. These clones, representing eight different genes, displayed enhanced expression under salt stress. Exploratory nucleotide sequencing was performed, and the predicted amino-acid sequence was compared with known gene sequences in the data-bank. Five of the cDNA clones were identified as a mitochondrial (mt) ATPase beta subunit, a mt ATPase subunit 9, a mt transport protein, a ubiquitin-extension protein and a ribosomal protein. Three cDNA clones could not be identified due to lack of adequate homology with known sequences. These results suggest that at least five genes with known function in cellular processes like ATP generation and protein synthesis, and three other genes of unknown identity, are greatly induced in saltadapted conditions.