Research Article

Table of Contents | Genet. Mol. Res. 2018 (3)

Displaying 16 - 19 of 19
Research Article

The identification of a single statistic that allows selection of superior genotypes for several agronomic traits with high experimental precision would be useful for bean breeding programs. We examined correlations between 12 statistics for agronomic traits to determine which would be useful for the selection of common bean lines that have superior agronomic performance. For this purpose, 21 experiments were carried out between 1998 and 2015, evaluating 156 common bean genotypes and seven agronomic traits. Error mean square presented a positive correlation estimate from intermediate to high magnitude with the coefficient of experimental variation and a significant minimum difference. Thus, these statistics are not adequate to evaluate the experimental precision of traits that confer high agronomic performance in common beans. Genotype mean square showed a positive correlation with the statistics: F-test value for genotype, coefficient of genetic variation, heritability, coefficient of relative variation and selective accuracy; these statistics were correlated with each other for most of the traits. Correlated statistics gave information similar as to the experimental precision of a trait, so they should not be used together. Selective accuracy (SA) is recommended as a classification measure of experimental precision in the selection of  common bean lines that have superior agronomic performance in Value of Cultivation and Use experiments. The SA makes the correct ranking of the common bean genotypes for agronomic performance traits possible, based on genetic superiority; consequently, SA should be implemented in common bean breeding programs.

Genet. Mol. Res. 17(3): GMR18042
DOI: 10.4238/gmr18042
Research Article

Myrcia ovata Cambess. (Myrtaceae) is a medicinal and aromatic plant that has analgesic, bactericidal and fungicidal properties. Even though this plant has economic potential, nothing is known about the variability and genetic diversity of this species. This information is necessary to establish conservation strategies and allow prospection of natural resources. The aim of this study was to evaluate the genetic diversity of M. ovata individuals of a native population in the municipality of Japaratuba, Sergipe State, Brazil, using Inter-Simple Sequence Repeat molecular markers (ISSR). Nine primers were tested, resulting in 99 polymorphic bands. The 24 individuals evaluated were clustered in two groups by the software Structure. The Jaccard similarity ranged from 0.21 (MYRO-034 and MYRO-159) to 0.82 (MYRO-178.1 and MYRO-178.2), with an average of 0.38. The genetic diversity of M. ovata was considered of medium level. The individuals MYRO-154, MYRO-175 and MYRO-175.1 presented the most variability.

Genet. Mol. Res. 17(3): GMR18022
DOI: 10.4238/gmr18022
Research Article

Endometriosis is characterized by ectopic endometrial tissue and affects millions of women worldwide. The disease leads to various symptoms such as chronic pelvic pain and infertility and does not yet have a well-defined etiology. The pathology is similar to cancer, since endometrial cells are highly proliferative, invade tissues and may be associated with tumor suppressor genes, including p53. Genetic polymorphisms are responsible for phenotypic variations in the population and the development of endometriosis is due to a combination of multiple genes and environmental factors. The Arg72Pro polymorphism of the p53 gene alters the amino acid 72 from arginine to proline and studies indicate that there is a considerable increase in the risk of cancer in patients with this polymorphism, because the protein becomes more susceptible to degradation. The eNOS gene participates in angiogenesis, a necessary factor for endometrial cells to survive outside the uterus and has increased expression in patients with endometriosis during the menstrual cycle. The Glu298Asp eNOS polymorphism is due to a point mutation of glutamate to aspartate, which can generate changes in its enzymatic activity. Aspartate generates protein products with different susceptibility to cleavage, functionally affecting the protein. We detected the Arg72Pro polymorphism of p53 and the Glu298Asp polymorphism of eNOS and estimated their prevalence in fertile and infertile patients diagnosed with endometriosis. The techniques used were conventional PCR and ARMS-PCR. Patients with Pro or Asp polymorphic alleles were found to be more susceptible to the development of endometriosis, and an association of these two polymorphisms is directly linked to infertility. The target genes p53 and eNOS can be used as molecular markers for endometriosis diagnosis, guiding prognosis and treatment, and may contribute to a better understanding of the pathophysiology of endometriosis.

Genet. Mol. Res. 17(3): GMR18046
DOI: 10.4238/gmr18046
Research Article

Our previous studies identified a Pseudomonas putida (Pt12 isolate) associated with roots of Piper tuberculatum Jacq., a Piperaceae occurring in the Amazon region with known resistance to infection by Fusarium solani f. sp. piperis, the causal agent of root rot disease in black pepper (Piper nigrum L.). This Pt12 isolate was able to inhibit in vitro growth of this fungus 39%. However, the inhibition mechanisms were unknown. Here, we searched for genes coding enzymes involved in the biosynthesis of compounds with potential antifungal activity in the Pt12 isolate, such as phenazine, pyoluteorin, 2,4-diacetylphloroglucinol and hydrogen cyanide. We found sequences potentially related to biosynthesis of phenazine (PhzF) based on DNA sequencing and comparative sequence analyses using the GenBank DataBase. PCR and nested PCR assays were used to isolate a 789-bp sequence coding for a deduced protein with 262 amino acid residues with high identity with a PhzF family phenazine biosynthesis protein from P. putida (WP_046785327.1), P. plecoglossicida (WP_041505738.1) and P. parafulva (WP_039578870.1). Molecular modeling and molecular dynamic simulations revealed that putative PhzF of Pt12 isolate could stably interact with substrate DHHA (Trans-2, 3-dihydro-3-hydroxyanthranilic acid) through some amino acid residues that are similar to conserved amino acids critical to the catalytic activity of a well-characterized PhzF protein produced by Pseudomonas fluorescens.

Genet. Mol. Res. 17(3): GMR18035
DOI: 10.4238/gmr18035