Recursos genômicos para a croadinha (mouriri elliptica mart. - melastomataceae)

Abstract

The Melastomataceae family, which has about 5,700 species, is ecologically and evolutionarily important, but lacks available genomic resources. This gap hinders advances in phylogenetic studies and in the conservation genetics of its species. Given this scenario, this thesis established as its central objective the generation and analysis of genomic data from Mouriri elliptica. Our aim is to build a solid knowledge base for the family and provide support for future genetic and evolutionary research. The results of this thesis are divided into three chapters. In the first, we review the literature on nucleic acid sequencing technologies, covering everything from the Sanger method to secondand third-generation approaches, such as those based on synthesis and single-molecule reading. We also discuss the principles of genome assembly and annotation, the importance of bioinformatics for analyzing large volumes of data, and the role of genomics in the conservation of plant genetic resources. The second chapter describes the sequencing and characterization of the chloroplast genome of M. elliptica, which had 156,791 base pairs, a typical circular structure, and four main regions: LSC (86,943 bp), SSC (17,234 bp), and two inverted regions (26,307 bp each). Seventy-nine protein-coding genes, four rRNA genes, and 30 tRNA genes were identified. Phylogenetic analysis placed the species close to the genus Memecylon, confirming its inclusion in the subfamily Olisbeoideae. The primers we developed for the MatK and rbcL genes were successful in in silico analyses for potential application as DNA barcodes, contributing to molecular identification within the family. The third chapter presents the partial assembly of the nuclear genome, consisting of 47,075 scaffolds, with an N50 of 26,418 bp and an estimated size of 354 Mb. The completeness assessment via BUSCO indicated 90.8% complete orthologs. A total of 6,602 microsatellite loci and 119,655 non-coding RNAs were identified, including rRNAs, tRNAs, miRNAs, and snoRNAs. Based on these data, primers were developed for microsatellite amplification in multiplex PCR systems. This thesis provides a set of genomic resources for M. elliptica, which contributes to the advancement of genomic knowledge of the genus. The characterization of the chloroplast and nuclear genomes broadens the understanding of the genomic diversity and evolutionary history of the species, while the molecular markers developed offer tools applicable to studies of diversity, population structure, and phylogeny, with potential for use in future conservation and management strategies.