Análise molecular in silico e palinológica de espécies de Amaryllidaceae J. ST. - Hil

Abstract

Amaryllidaceeae is a family of monocotyledons that comprises 1600 species, being of wide occurrence in the world. In Brazil, 134 species are registered, distributes in all regions, where the genus Allium is the most important from the agronomic point of view. Within this family the insecticidal action of many lectins has been demonstrated in trial with transgenic plants. Bioinformatics is a major ally of genetic breeding programs using the in-silico approach to identify, characterize and predict protein domains. In addition, this approach has used plastid genomes for phylogenetic inferences and verified the occurrence of microsatellites to analyze the genetic distance between individuals and identification of cultivars. Just as pollen analysis is used in breeding programs to verify the possibility of hybridization. The objective of this research is the use of bioinformatics tools for molecular and palynological in silico analysis in species of the Amaryllidaceae family. Mannose-specific binding lectin sequences were taken from GenBank. Physical-chemical parameters, identification of domains and estimation of functional effects were perfomed by ProtParam, Prodom ans SNAP2. Phylogenetic trees were constructed by the MEGA 7 Program. Prediction, evaluation and validation of the tertiary structure of the models were perfomed by the server Phyre2, Molprobity, ProSA-web and Yasara force Field. Plastidial genoma of fifteen species was used to localize the microsatellite regions through Gramene and the Dogma server. Phylogenetic analysis of the plastidial genome was perfomed by the MEGA software and the matK marker by the BEAST. For the palynological analysis, 25 pollen grains from thirteen species were analyzed by optical microscopy and the palynological descriptions for most species followed this order: size, chape, scope and apertures. The results obtained between specific mannose lectin sequences revealed the presence of two mutation-sensitive functional motifs, a hydrophilic character and a large isoelectric point amplitude with species acting from acidic to alkaline media. Genomic analysis showed the presence of microsatellites in the rpoC2, cemA, ycf2 and ycf2.1 genes. However, most of the microsatallites were located in the intergenic regions. It was observed that the microsatellites as to the type are perfect and imperfect, where the imperfect type was due to transitional and transverse mutations. In the palynological analysis, the results indicate that the pollen grains are of the oblate and peroblato type, monosulcated, with a larger equatorial length of the pollen grains ranging from 22,5 to 145 μm and smaller equatorial length of the pollen grains of 16,25 to 93,75 μm among genus. In Amaryllidaceae, morphometry and pollen shape are not a barrier to the occurrence of hybrids. The results presented will be very useful as regards the importance of the use of in silico molecular and palynological tools. Together, this information can help family genetic improvement programs, either through conventional methods or through biotechnology.