BACs symbolizing one another collection of loci hybridizing to help you probes SbRPG661, SbRPG373 and you will SbRPG851 was indeed sequenced with the objective out of relationship this new lifetime of duplication in accordance with new divergence of your own Musa and you will grain lineages

We also analyzed the 18,612 ginger (Zingiber officinale; Zingiberaceae, Zingiberales) EST-derived unigenes available on the TIGR Plant Transcript Assemblies web site (sequences generated by David Gang, University of Arizona) and found no evidence of large-scale duplication in the K_s distribution for paralogous pairs (Figure 8). Moreover, the modal K_s for reciprocal best matches between the Musa and Zingiber unigene sets is 0.78 (Figure 8), larger than the mode for Musa paralogous pairs. The age of the most recent common ancestor for the Musacaceae and Zingiberaceae is estimated at 87 Mya [3, 72, 73]. This implies an average synonymous substitution rate of 4.5 per 10 9 years (0.78 synonymous substitutions per site/(2*87,000,000 years)), intermediate between rates estimated for the Poaceae (6.1–6.5 per 10 9 years) and palms in the order Arecales (2.61 per 10 9 years; . We must emphasize that all of these rate estimates are approximate, based on rough estimates of minimum divergence times. However, regardless of ambiguities in substitution rate calibrations, our results indicate that the predicted large-scale duplication that occurred in the Musa lineage (K_s = 0.55) post-dates the divergence of lineages leading to Zingiber and Musa (K_s = 0.78), but occurred well before the separation of Musa A and Musa B (K_s = 0.0410).

K_s values were also computed on 1,034 pairs of homologous genes identified between the Musa ESTs and the rice genome sequences. As expected, the distribution of K_s values between rice-Musa homologs form a single peak centred around K_s = 1.7 (Figure 8). Using this K_s value to estimate the age of http://hookupranking.com/women-looking-for-men the Poales-Zingiberales split is less straightforward than described above for the Musa-Zingiber split, because synonymous substitution rates clearly vary between these Commelinid monocot lineages.

BAC fingerprint analyses revealed that whereas SbRPG854 hybridized to a single locus in the Musa genome, SbRPG probes SbRPG132 hybridized to 6 regions, SbRPG663 hybridized to 5 loci, and two loci were identified for SbRPG373, SbRPG661 and SbRPG851 (Table 1 and Additional file 1). Pair-wise estimations of K_s, the number of synonymous substitutions per synonymous site, were 0.93 (± 0.25), 1.39 (± 0.19) and 1.43 (± 0.60) for Musa homologs of the coding regions of SbRPG661 (thioredoxin), SbRPG851 (phosphoglycerate kinase) and SbRPG373 (hypothetical protein), respectively. Phylogenetic analyses suggested that the SbRPG851 Musa homologs duplicated prior to the divergence of the Poales and the Zingiberales, (probably independent from the large-scale duplication described above), and the SbRPG661 and SbRPG373 Musa homologs are sister to each other in the gene tree, suggesting the duplications arose after the divergence of the Poales and the Zingiberales (data not shown).

I in addition to examined the level of conservation between genomic nations related SbRPG661, SbRPG851 and you may SbRPG373 recurring genetics inside the Musa and you will rice and discovered zero synteny from inside the regions anchored from the such homologs. Which absence of synteny might be said because of the duplication events and you can then gene losings otherwise by translocation of focal genetics.

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step one.8 Mb regarding Musa genomic series revealed that every BACs reviewed was in fact gene rich having a reduced posts of transposable function. The analyses from 443 Musa family genes predict revealed that Musa genetics generally have an excellent „rice-like“ bimodal GC distribution with a very asymmetrical and you will long tail with the high GC stuff like in past knowledge [43, 44]. Yet not, the next family of „Arabidopsis-like“ genes was discover with an overall total reasonable GC content without tall gradient across the programming sequence. Compared to a previous testing out of turf and you can low-yard monocots [52, 53], our very own analyses recommend that Zingeberales genetics show some features with the genomes off each other eudicots and you will people in the new Poaceae. Which effect implies that brand new Musa genome is more like cereal genomes in accordance with onion, asparagus therefore the basal-most monocot lineage, Acorus.