RESUMEN
The recovery of ancient RNA from archeological material could enable the direct study of microevolutionary processes. Small RNAs are a rich source of information because their small size is compatible with biomolecular preservation, and their roles in gene regulation make them likely foci of evolutionary change. We present here the small RNA fraction from a sample of archeological barley generated using high-throughput sequencing that has previously been associated with localized adaptation to drought. Its microRNA profile is broadly similar to 19 globally distributed modern barley samples with the exception of three microRNAs (miRNA159, miRNA319, and miR396), all of which are known to have variable expression under stress conditions. We also found retrotransposon activity to be significantly reduced in the archeological barley compared with the controls, where one would expect the opposite under stress conditions. We suggest that the archeological barley's conflicting stress signals could be the result of long-term adaptation to its local environment.
Asunto(s)
Hordeum/genética , ARN de Planta/genética , Adaptación Fisiológica , Secuencia de Bases , ADN Antiguo , Regulación de la Expresión Génica de las Plantas/genética , Germinación/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Historia Antigua , MicroARNs/genética , ARN/análisis , ARN de Planta/historia , Análisis de Secuencia de ARN/métodos , Estrés Fisiológico/genéticaRESUMEN
This article presents an Integrative Model of Sustainable Health Decision-Making and a toolkit to equip U.S. Extension professionals with knowledge and skills to engage in adult immunization education. The objective was to reduce mistrust and increase willingness and confidence toward delivering vaccination education. The model was developed through an explanatory parallel mixed methods design. Data collection included a needs assessment survey, interviews, workshops, and Neuromarketing message testing. The resulting toolkit was pilot tested before final delivery. Four key needs were identified: tailoring trainings based on Extension roles, prioritizing preserving community trust and professional credibility, establishing connections with medical experts, and strengthening Science Media Literacy skills to counter misinformation and communicate emerging science. Correlations among constructs supported an integrated model focused on a professional development core of Science Media Literacy, Motivational Interviewing, and Neuromarketing Science that strengthens communication relationships between priority populations and trusted partners. The model and work described in this article can serve as a general framework for engaging key influencers in communities in communication education intended to promote sustainable well-being, such as increasing vaccine uptake.
RESUMEN
Transposable elements (TEs) are drivers of evolution resulting in episodic surges of genetic innovation and genomic reorganization (Oliver KR, Greene WK. 2009. TEs: powerful facilitators of evolution. Bioessays 31:703-714.), but there is little evidence of the timescale in which this process has occurred (Gingerich PD. 2009. Rates of evolution. Ann Rev Ecol Evol Syst. 40:657-675.). The paleontological and archaeological records provide direct evidence for how evolution has proceeded in the past, which can be accessed through ancient DNA to examine genomes using high-throughput sequencing technologies (Palmer SA, Smith O, Allaby RG. 2011. The blossoming of plant archaeogenetics. Ann Anat. 194:146-156.). In this study, we report shotgun sequencing of four archaeological samples of cotton using the GS 454 FLX platform, which enabled reconstruction of the TE composition of these past genomes and species identification. From this, a picture of lineage specific evolutionary patterns emerged, even over the relatively short timescale of a few thousand years. Genomic stability was observed between South American Gossypium barbadense samples separated by over 2,000 miles and 3,000 years. In contrast, the TE composition of ancient Nubian cotton, identified as G. herbaceum, differed dramatically from that of modern G. herbaceum and resembled closely the A genome of the New World tetraploids. Our analysis has directly shown that considerable genomic reorganization has occurred within the history of a domesticated plant species while genomic stability has occurred in closely related species. A pattern of episodes of rapid change and periods of stability is expected of punctuated evolution. This observation is important to understanding the process of evolution under domestication.
Asunto(s)
Evolución Molecular , Genoma de Planta/genética , Genómica/métodos , Gossypium/genética , Paleontología , Metagenoma/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Especificidad de la EspecieRESUMEN
The evolution of domesticated cereals was a complex interaction of shifting selection pressures and repeated episodes of introgression. Genomes of archaeological crops have the potential to reveal these dynamics without being obscured by recent breeding or introgression. We report a temporal series of archaeogenomes of the crop sorghum (Sorghum bicolor) from a single locality in Egyptian Nubia. These data indicate no evidence for the effects of a domestication bottleneck, but instead reveal a steady decline in genetic diversity over time coupled with an accumulating mutation load. Dynamic selection pressures acted sequentially to shape architectural and nutritional domestication traits and to facilitate adaptation to the local environment. Later introgression between sorghum races allowed the exchange of adaptive traits and achieved mutual genomic rescue through an ameliorated mutation load. These results reveal a model of domestication in which genomic adaptation and deterioration were not focused on the initial stages of domestication but occurred throughout the history of cultivation.
Asunto(s)
Domesticación , Sorghum/genética , Adaptación Fisiológica/genética , Productos Agrícolas/genética , Productos Agrícolas/historia , Historia Antigua , Hibridación Genética/genética , Carácter Cuantitativo HeredableRESUMEN
BACKGROUND: Archaeobotanical samples of barley (Hordeum vulgare L.) found at Qasr Ibrim display a two-row phenotype that is unique to the region of archaeological sites upriver of the first cataract of the Nile, characterised by the development of distinctive lateral bracts. The phenotype occurs throughout all strata at Qasr Ibrim, which range in age from 3000 to a few hundred years. METHODOLOGY AND FINDINGS: We extracted ancient DNA from barley samples from the entire range of occupancy of the site, and studied the Vrs1 gene responsible for row number in extant barley. Surprisingly, we found a discord between the genotype and phenotype in all samples; all the barley had a genotype consistent with the six-row condition. These results indicate a six-row ancestry for the Qasr Ibrim barley, followed by a reassertion of the two-row condition. Modelling demonstrates that this sequence of evolutionary events requires a strong selection pressure. CONCLUSIONS: The two-row phenotype at Qasr Ibrim is caused by a different mechanism to that in extant barley. The strength of selection required for this mechanism to prevail indicates that the barley became locally adapted in the region in response to a local selection pressure. The consistency of the genotype/phenotype discord over time supports a scenario of adoption of this barley type by successive cultures, rather than the importation of new barley varieties associated with individual cultures.