Additionally, Histoplasma capsulatum, a fungus belonging to the same class as the Aspergilli, contains ppoD and also does not contain ppoB, but is able to produce sexual spores [3]. Expression analysis of A. niger ppoA, ppoC and ppoD shows that these genes are expressed and their

expression levels depend on the Quisinostat supplier fungus’ developmental stage (Fig. 4). It should be noted that A. niger is heterothallic and requires mating between two isolates with different mating types. Despite the fact that A. niger appears to contain all the genes required for a sexual cycle, until now, no sexual cycle has been observed for A. niger on any of a broad range of growth conditions (Paul Dyer, personal communication). In contrast, A. nidulans is a homothallic species in which both mating types are present in a single strain and can therefore cross with itself. This difference might hint towards different strategies for regulation of sexual and asexual development. Studies of these genes in other homothallic and heterothallic Aspergilli, could demonstrate whether this is a general difference between homothallic and heterothallic species. This could include the presence or absence of expression of specific dioxygenase genes. Strictly

asexual species are considered an evolutionary endpoint, and truly asexual species are thought to be extremely rare [5]. Sequencing of fungal genomes and comparative buy KU55933 analysis of sexual and asexual species show that fungi that have long been considered asexual organisms, may have a latent potential for sexual reproduction [1, 6]. Nevertheless, the presence of sex related genes alone, does not confirm sexual reproduction. Conclusion This study shows that A. niger produces the same oxylipins and

has similar dioxygenase genes as A. nidulans. Even though, the VEGFR inhibitor functionality of these genes remains as yet to be proven, their presence could point towards the existence of sexual reproduction in A. niger or a broader role for the gene products in physiology, than just sexual development. Methods Materials All chemicals used were commercially obtained and of analytical grade. Linoleic acid (9Z,12Z-octadecadienoic acid, 18:2, 99% pure), arachidonic acid, 5Z,8Z,11Z,14Z-eicosatetraenoic Resminostat acid, 20:4, 99% pure) and margaric acid (heptadecanoic acid, 17:0, 99% pure) were obtained from Sigma (St. Louis, MO). [U-13C] 18:2 (99% pure) was obtained from Isotec (Matheson Trigas, Irving, TX). Solutions of 30 mM fatty acid were stored in methanol under N2 at -20°C until use. Strains, media and culture conditions Aspergillus strains used are listed in Table 2. Cultures were grown in minimal medium containing trace elements and 1% glucose as carbon source, unless otherwise indicated in the text [15]. Appropriate supplements (8 μM nicotinamide, 1.