RESUMEN
Among Meliponini species, c-heterochromatin can occupy large portions of chromosomes. This characteristic could be useful for understanding evolutionary patterns of satellite DNAs (satDNAs), although few sequences have been characterized in these bees. In Trigona, phylogenetically represented by clades A and B, the c-heterochromatin is mostly located in one chromosome arm. Here we used different techniques, including restriction endonucleases and genome sequencing followed by chromosomal analysis, to identify satDNAs that may be contributing to the evolution of c-heterochromatin in Trigona. Our results revealed a highly abundant ThyaSat01-301 satDNA, corresponding to about 13.77% of the Trigona hyalinata genome. Another seven satDNAs were identified, one corresponding to 2.24%, and the other six corresponding to 0.545% of the genome. The satDNA ThyaSat01-301 was shown to be one of the main constituents of the c-heterochromatin of this species, as well as of other species belonging to clade B of Trigona. However, this satDNA was not observed on the chromosomes of species from clade A, demonstrating that the c-heterochromatin is evolving divergently between species of clade A and B, as a consequence of the evolution of repetitive DNA sequences. Finally, our data suggest the molecular diversification of the karyotypes, despite a conservated macrochromosomal structure on the genus.
Asunto(s)
ADN Satélite , Heterocromatina , Abejas/genética , Animales , Evolución Molecular , Mapeo Cromosómico , Secuencia de BasesRESUMEN
Satellite DNAs (satDNAs) and transposable elements (TEs) are among the main components of constitutive heterochromatin (c-heterochromatin) and are related to their functionality, dynamics, and evolution. A peculiar case regarding the quantity and distribution of c-heterochromatin is observed in the genus of bees, Melipona, with species having a low amount of heterochromatin and species with high amount occupying almost all chromosomes. By combining low-pass genome sequencing and chromosomal analysis, we characterized the satDNAs and TEs of Melipona quadrifasciata (low c-heterochromatin) and Melipona scutellaris (high low c-heterochromatin) to understand c-heterochromatin composition and evolution. We identified 15 satDNA families and 20 TEs for both species. Significant variations in the repeat landscapes were observed between the species. In M. quadrifasciata, the repetitive fraction corresponded to only 3.78% of the genome library studied, whereas in M. scutellaris, it represented 54.95%. Massive quantitative and qualitative changes contributed to the differential amplification of c-heterochromatin, mainly due to the amplification of exclusive repetitions in M. scutellaris, as the satDNA MscuSat01-195 and the TE LTR/Gypsy_1 that represent 38.20 and 14.4% of its genome, respectively. The amplification of these two repeats is evident at the chromosomal level, with observation of their occurrence on most c-heterochromatin. Moreover, we detected repeats shared between species, revealing that they experienced mainly quantitative variations and varied in the organization on chromosomes and evolutionary patterns. Together, our data allow the discussion of patterns of evolution of repetitive DNAs and c-heterochromatin that occurred in a short period of time, after separation of the Michmelia and Melipona subgenera.
Asunto(s)
Genómica , Heterocromatina , Animales , Abejas/genética , Mapeo Cromosómico , Elementos Transponibles de ADN , ADN Satélite/genética , Evolución Molecular , Heterocromatina/genéticaRESUMEN
Significant advances in the understanding and management of Duchenne muscular dystrophy (DMD) have occurred since the publication of international guidelines for DMD care in 2010. Our objective was to provide an evidence-based national consensus statement for multidisciplinary care of DMD in Brazil. A combination of the Delphi technique with a systematic review of studies from 2010 to 2016 was employed to classify evidence levels and grade of recommendations for the guideline. Our recommendations were divided in two parts. Guideline methodology and overall disease concept descriptions are found in Part 1. Here we present Part 2, where we provide the results and recommendations on rehabilitation and systemic care for DMD.
Asunto(s)
Distrofia Muscular de Duchenne/rehabilitación , Grupo de Atención al Paciente , Brasil , Consenso , HumanosRESUMEN
ABSTRACT Significant advances in the understanding and management of Duchenne muscular dystrophy (DMD) have occurred since the publication of international guidelines for DMD care in 2010. Our objective was to provide an evidence-based national consensus statement for multidisciplinary care of DMD in Brazil. A combination of the Delphi technique with a systematic review of studies from 2010 to 2016 was employed to classify evidence levels and grade of recommendations for the guideline. Our recommendations were divided in two parts. Guideline methodology and overall disease concept descriptions are found in Part 1. Here we present Part 2, where we provide the results and recommendations on rehabilitation and systemic care for DMD.
RESUMO Avanços significativos na compreensão e no manejo da Distrofia Muscular de Duchenne (DMD) ocorreram desde a publicação de diretrizes internacionais para o cuidado destes pacientes em 2010. Nosso objetivo foi elaborar um consenso nacional baseado em evidências para o cuidado multidisciplinar dos pacientes com DMD no Brasil. Utilizamos uma combinação da técnica de Delphi com uma revisão sistemática da literatura de 2010 a 2016 para classificarmos os níveis de evidência e graus de recomendação para o consenso. Nossas recomendações foram divididas em duas partes. A metodologia utilizada na elaboração do consenso e conceitos gerais da doença encontram-se na parte 1. Neste artigo fornecemos os resultados e recomendações sobre reabilitação e cuidados sistêmicos para DMD.