Albuquerque Patrícia, Baptista Alessandra J, Derengowsky Lorena da Silveira, Procópio Luciano, Nicola André Moraes, Arraes Fabrício B M, Souza Diorge Paulo de, Kyaw Cynthia Maria, Silva-Pereira Ildinete
Instituto de Biologia, Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Asa Norte, 70910-900 Brasília, DF, Brazil.
Genet Mol Res. 2005 Jun 30;4(2):251-72.
The RNA biogenesis machinery of Paracoccidioides brasiliensis was assessed by comparative analyses of PbAESTs (P. brasiliensis assembled expressed sequence tags (ESTs)) with sequences from Saccharomyces cerevisiae MIPS database. PbAESTs related to almost all categories of S. cerevisiae RNA biogenesis were found. Two of the 12 S. cerevisiae RNA Pol II core subunits, Rpb3 and Rpb7, were found, probably reflecting the growth phase from which the cDNA libraries used in ESTs generation were constructed, as well as the low abundance of some of these transcripts. We have also found orthologs to TATA-box-binding protein (TBP), and at least one subunit of each TBP-associated factors (TFII) in P. brasiliensis transcriptome, except TFIIB. Genes associated to the chromatin remodeling complex, as well as transcription factors probably involved in the control of genes associated to a sexual cycle and virulence, were also identified. With respect to the pre-mRNA processing, 65 PbAEST orthologs to S. cerevisiae basal splicing machinery and 21 orthologs of 5'- and 3'-end formation processes were found. Components involved in RNA interference were detected, suggesting that this gene expression regulation mechanism is probably used by P. brasiliensis. Twelve PbAESTs related to Pol I and Pol III machineries were assigned as S. cerevisiae orthologs. Finally, 25 and 10 PbAESTs associated to rRNA and tRNA processing, respectively, were detected. Taken together, our results enable us to depict, for the first time, a global view of transcription and RNA processing in P. brasiliensis.
通过将巴西副球孢子菌的组装表达序列标签（PbAESTs）与酿酒酵母MIPS数据库中的序列进行比较分析，评估了巴西副球孢子菌的RNA生物合成机制。发现了与酿酒酵母RNA生物合成几乎所有类别的PbAESTs。发现了酿酒酵母12个RNA聚合酶II核心亚基中的两个，Rpb3和Rpb7，这可能反映了用于生成ESTs的cDNA文库所构建的生长阶段，以及其中一些转录本的低丰度。我们还在巴西副球孢子菌转录组中发现了TATA框结合蛋白（TBP）的直系同源物，以及每个TBP相关因子（TFII）的至少一个亚基，但不包括TFIIB。还鉴定了与染色质重塑复合体相关的基因，以及可能参与控制与有性周期和毒力相关基因的转录因子。关于前体mRNA加工，发现了65个与酿酒酵母基础剪接机制直系同源的PbAESTs，以及21个5'和3'末端形成过程的直系同源物。检测到参与RNA干扰的成分，这表明巴西副球孢子菌可能使用这种基因表达调控机制。1十二个与聚合酶I和聚合酶III机制相关的PbAESTs被指定为酿酒酵母直系同源物。最后，分别检测到25个和10个与rRNA和tRNA加工相关的PbAESTs。综上所述，我们的结果首次使我们能够描绘出巴西副球孢子菌转录和RNA加工的全局视图。
