Transcriptional profiling analysis of S. pombe kinase deletin strains treated (60min) or untreated (0min) with nitrogen starvation in comparison with a common reference.

Kinase deletion strains treated with or without nitrogen starvation Background: Protein kinase-mediated signaling pathways play a pivotal role in regulation of stress responses. Nitrogen starvation (NS) induces sexual development when mating partner available or entry into a quiescent state (G0) in heterothallic background. However, it is unclear whether transcriptional profiles in response to NS allows distinguishing between kinase deletion strains defective in sexual development and/or G0-arrest. Results: In this study, we used DNA microarray to analyze transcriptional profiles in 68 protein kinase deletion strains prior to and after NS. Microarray analyses indicated that NS-induced transcriptional profiles of all kinase strains plus wild type are highly correlated with one another (i.e., Pearson¡¯s correlation coefficient r > 0.7) except for that of pka1¦¤, which showed no high correlation with other 11 kinase strains. Significantly, 9 of 11 strains were defective in sexual development, suggesting that the NS-induced profile of pka1¦¤ serves as a signature with no high correlation with profiles of kinase strains defective in sexual development. Furthermore, we show that expression of the NS-induced genes is elevated in pka1¦¤ and cyr1¦¤ strains prior to NS. On the other hand, levels of the NS-induced genes expression in pka1¦¤, cyr1¦¤, sty1¦¤, and byr1¦¤ are significantly lower than that of wild type. Conclusions: Taken together, our analyses indicate that the cAMP-dependent Pka1-mediated signaling pathway play a major role in regulation of the NS-induced genes prior to and after NS. In addition, the ROS-activated kinase Sty1 and the pheromone-induced kinase Byr1 are also involved in up-regulation of NS-induced genes upon NS stress. 68 kinase deletion strains and other 5 deletion strains were treated with (60m) or without (0min) nitrogen starvation