Відмінності між версіями «Fulvestrant Constructors Join Forces»

Поточна версія на 12:59, 17 червня 2017

Results and discussion The ancestral duplicated ribosomal genomic region in ��Ca. tremblaya�� Reductive evolution in obligate endosymbiont genomes is mostly due to the loss of genes that become redundant and/or unnecessary in the intracellular niche (McCutcheon and Moran, 2012). However, even though ��Ca. Tremblaya princeps�� from P. citri (cluster E) displays one of the most reduced genomes known so far, it presents an identical 5702-bp redundant sequence. It includes the complete ribosomal operon (rrs, rrl, and rrf) and its closest genomic context (the 3�� region of leuA, encoding the alpha-isopropylmalate synthase, EC 2.3.3.13; rpsO, encoding the ribosomal protein S15; and the 5�� region of rsmH, encoding the 16S rRNA m4C1402 methyltransferase, EC 2.1.1.199) (Figure ?(Figure1).1). Detection of this duplicated region also in ��Ca. Tremblaya princeps�� strains from Dysmicoccus brevipes (cluster A), Melanococcus albizziae (cluster C), Maconellicoccus australiensis, and Maconellicoccus hirsutus (cluster F) led authors to suggest that a segmental duplication occurred at early stages of ��Ca. Tremblaya princeps�� diversification (Baumann et al., 2002). In order to study the origin of such duplication event, we performed a comparative analysis between the complete genomes of ��Ca. Tremblaya princeps�� PCVAL (L��pez-Madrigal et al., 2011) and ��Ca. Tremblaya phenacola�� PAVE (Husnik et al., 2013). The analysis revealed the presence of an identical 386-bp inverted duplication in the latter. It is mostly composed by the remnants of the degraded ribosomal operon, including the 3�� end of a pseudogenized 23S rRNA gene (rrl, not annotated originally in the genome), the 5S rRNA gene (rrf) and the corresponding intergenic sequence. It also includes the TPPAVE_188 pseudogene, which is a truncated paralog of rsmH (Figure ?(Figure1).1). This result suggests that the segmental duplication took place before the split of the two ��Ca. Tremblaya�� lineages. Moreover, the original copy of the ribosomal operon has undergone massive decay in ��Ca. Tremblaya Veliparib phenacola,�� while the two identical copies preserved in ��Ca. Tremblaya princeps�� have evolved in a concerted manner. Figure 1 Duplicated genomic regions in Pseudococcidae beta-endosymbionts. (A) ��Ca. Tremblaya princeps�� PCVAL; (B) ��Ca. Tremblaya phenacola�� PAVE. Bars indicate the ��Ca. Tremblaya princeps�� fragments amplified in ... Co-occurrence of concerted evolution and HR-related genes in pseudococcinae endosymbiotic systems Since both ��Ca. Tremblaya�� have a common evolutionary origin and ��Ca. Tremblaya phenacola�� has remained alone in the bacteriocytes of Phenacoccinae mealybugs (Gruwell et al., 2010; Koga et al., 2013), the massive decay of the paralogous loci in ��Ca. Tremblaya phenacola�� suggests that a link might exist between nested endosymbiosis and concerted evolution in ��Ca. Tremblaya princeps.