<p> Con struction of the NA1363 strain Around 0.5 to 1 µg of DNA (circular double stranded) corresponding to the pBRgpdAp-LacZ-ribo plasmid were used to transform the NA0720 strain (pantoB100 biA1 argB2 riboB2, thus auxotroph for the D-pantothenic acid, biotin, arginine and riboflavin), using the method described by Tilburn et al. (1983). The [ribo+] prototroph transformants were, after their purification, replicated on supplemented minimal medium (with glucose and ammonium as sole carbon and nitrogen source, respectively), containing XGAL (final concentration of 50 µg/mL), in order to identify the transformants expressing the lacZ gene. Note that under these conditions (i.e., in presence of glucose as the sole carbon source), the wild-type strain did not produce blue colonies in presence of XGAL. Fifty transformants [ribo+, β- galactosidase+] were so identified, and analyzed by Southern-blot in order to determine the copy number of integrated plasmid and eventually the locus of integration. Only eighteen transformants harbored a single copy of the plasmid, integrated either at the gpdA locus (for eight of them), at the riboB locus (five of them), or in ectopic position (for the others). One of these ectopic transformant was chosen and crossed to the CV125 strain (pabaA1, i.e., auxotroph for the p-aminobenzoic acid) in order to generate the NA1363 strain (pabaA1 pBR-gpdAp-lacZ-riboB), (the presence of the wild-type allele for the riboB gene was confirmed by a second cross). The NA1363 strain was used to create a diploid strain with the G059 master strain MSF from the Glasgow collection (a gift from Pr John Clutterbuck). This master strain carries a marker on each chromosome (Chromosome I: suA1adE20 yA2 adE20, II: acrA1, III: galA1, IV: pyroA4, V: facA300, VI: sB43, VII: nicB8, VIII: riboB2). After haploidisation of this diploid in the presence of benomyl (at the final concentration of 0.6 µg/mL), 128 haploids sectors permitted to determine that the plasmid pBRgpdAp-lacZ-ribo was integrated somewhere in the chromosome VIII of A. nidulans.</p><p>Tilburn, J., C. Scazzocchio, G. G. Taylor, J. H. Zabicky-Zissman, R. A. Lockington et al., 1983 Transformation by integration in Aspergillus nidulans. Gene 26: 205–221</p><p>Current Genetics Development and validation of a custom microarray for global transcriptome profiling of the fungus Aspergillus nidulans Claudine Deloménie, Guido Grentzmann, Nathalie Oestreicher, Robin Mesnage, Christian Vélot Corresponding Author: C. Deloménie E-mail: [email protected] - Phone: (33) 1 46 83 57 85 – Fax: (33) 1 46 83 58 03</p>