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1.
Front Plant Sci ; 12: 605937, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33828569

RESUMEN

African countries face key challenges in the deployment of GM crops due to incongruities in the processes for effective and efficient commercial release while simultaneously ensuring food and environmental safety. Against the backdrop of the preceding scenario, and for the effective and efficient commercial release of GM crops for cultivation by farmers, while simultaneously ensuring food and environmental safety, there is a need for the close collaboration of and the interplay between the biosafety competent authorities and the variety release authorities. The commercial release of genetically modified (GM) crops for cultivation requires the approval of biosafety regulatory packages. The evaluation and approval of lead events fall under the jurisdiction of competent national authorities for biosafety (which may be ministries, autonomous authorities, or agencies). The evaluation of lead events fundamentally comprises a review of environmental, food, and feed safety data as provided for in the Biosafety Acts, implementing regulations, and, in some cases, the involvement of other relevant legal instruments. Although the lead GM event may be commercially released for farmers to cultivate, it is often introgressed into locally adapted and farmer preferred non-GM cultivars that are already released and grown by the farmers. The introduction of new biotechnology products to farmers is a process that includes comprehensive testing in the laboratory, greenhouse, and field over some time. The process provides answers to questions about the safety of the products before being introduced into the environment and marketplace. This is the first step in regulatory approvals. The output of the research and development phase of the product development cycle is the identification of a safe and best performing event for advancement to regulatory testing, likely commercialization, and general release. The process of the commercial release of new crop varieties in countries with established formal seed systems is guided by well-defined procedures and approval systems and regulated by the Seed Acts and implemented regulations. In countries with seed laws, no crop varieties are approved for commercial cultivation prior to the fulfillment of the national performance trials and the distinctness, uniformity, and stability tests, as well as prior to the approval by the National Variety Release Committee. This review outlines key challenges faced by African countries in the deployment of GM crops and cites lessons learned as well as best practices from countries that have successfully commercialized genetically engineered crops.

2.
BMC Proc ; 12(Suppl 8): 11, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30079102

RESUMEN

The New Partnership for Africa's Development (NEPAD) Agency recognizes that Africa is in a period of transition and that this demands exploring and harnessing safe advances made in science-based innovations including modern biotechnology. To advance the science of biotechnology in Africa effectively, while at the same time safeguarding human health and the environment, the African Union (AU) adopted a High-Level Panel report on modern biotechnology entitled, Freedom to Innovate, which advocated for a coevolutionary approach where technology development goes hand in hand with regulation. Furthermore, most AU member states are Parties to the Cartagena Protocol on Biosafety (CPB), a legally binding international agreement negotiated, concluded and adopted within the framework of the Convention on Biological Diversity. This seeks to guide Parties in developing systems for the environmentally sound management of modern biotechnology applications. Currently, 49 AU Member States have signed and ratified the CPB, of which 12 have passed biosafety laws. African Union (AU) member states are at different stages in the development of regulatory frameworks for applications of modern biotechnology, which include genetically modified (GM) products and other emerging technologies. Biosafety regulatory frameworks comprise: biotechnology and/or biosafety policy; laws, regulations and guidelines; administrative systems; decision-making systems; and mechanisms for public engagement. To assist Member States to implement functional regulatory frameworks for both agriculture and health applications, the NEPAD Agency established the African Biosafety Network of Expertise (ABNE) and the African Medicines Regulatory Harmonization (AMRH). Currently, transgenic insects and GM crops are regulated by Competent National Authorities whose mandate derives from national biosafety laws. For GM crops, a lot of research has been conducted up to the confined field trial (CFT) and multi-location trials stages in a number of African countries. Burkina Faso has fully functional containment facilities for transgenic mosquitoes while Mali and Uganda are developing theirs. The Burkina Faso regulatory agency has granted permits and has already received sets of sterile mosquito eggs for trials in the contained facility. It is instructive to note that both ABNE and AMRH have worked with national and regional regulatory bodies in Africa to enhance their technical capacities for informed decision making, adoption of best practices, and compliance with international standards. It is against the backdrop of a rich blend of on-the-ground knowledge, experience, expertise, and insight into the context and political sensitivities of member states that the NEPAD Agency seeks to expand existing support. This would include capacity strengthening in the regulation of emerging technologies, such as the application of gene drives in the development of transgenic mosquito for the control of malaria transmission.

3.
Proc Natl Acad Sci U S A ; 113(39): 11040-5, 2016 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-27621466

RESUMEN

Micronutrient deficiencies are common in locales where people must rely upon sorghum as their staple diet. Sorghum grain is seriously deficient in provitamin A (ß-carotene) and in the bioavailability of iron and zinc. Biofortification is a process to improve crops for one or more micronutrient deficiencies. We have developed sorghum with increased ß-carotene accumulation that will alleviate vitamin A deficiency among people who rely on sorghum as their dietary staple. However, subsequent ß-carotene instability during storage negatively affects the full utilization of this essential micronutrient. We determined that oxidation is the main factor causing ß-carotene degradation under ambient conditions. We further demonstrated that coexpression of homogentisate geranylgeranyl transferase (HGGT), stacked with carotenoid biosynthesis genes, can mitigate ß-carotene oxidative degradation, resulting in increased ß-carotene accumulation and stability. A kinetic study of ß-carotene degradation showed that the half-life of ß-carotene is extended from less than 4 wk to 10 wk on average with HGGT coexpression.


Asunto(s)
Alimentos Fortificados , Sorghum/metabolismo , Vitamina E/metabolismo , beta Caroteno/metabolismo , Cromatografía Líquida de Alta Presión , ADN Bacteriano/genética , Endospermo/metabolismo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Semillas/metabolismo , Sorghum/enzimología , Sorghum/genética
4.
Electron. j. biotechnol ; 19(4): 52-61, July 2016. ilus
Artículo en Inglés | LILACS | ID: lil-793953

RESUMEN

Background: Introgression of transgenes from crops to their wild species may enhance the adaptive advantage and therefore the invasiveness of and weedy forms. The study evaluated the effect of Africa Biofortified Sorghum (ABS) genes from ABS event 188 on the vegetative and reproductive features of the F2 populations derived from crosses with Sorghum bicolor subsp. drummondii. Results: F1 populations were obtained from reciprocal crosses involving ABS event 188 and its null segregant with inbred weedy parents from S. bicolor subsp. drummondii. Four F2 populations and four parental populations were raised in RCBD with 4 replications in a confined field plot for two seasons. Vegetative and reproductive traits were evaluated. The vigour shown in the F2 populations from the reciprocal crosses involving ABS event 188 and S. bicolor subsp. drummondii was similar to that in the crosses involving the null segregant and S. bicolor subsp. drummondii. Differences in vegetative and reproductive parameters were observed between the parental controls and the F2 populations. Examination of the above and below ground vegetative biomass showed lack of novel weedy related features like rhizomes. Conclusions: Therefore, release of crops with ABS 188 transgenes into cropping systems is not likely to pose a risk of conferring additional adaptive advantage in the introgressing populations. The interaction of ABS genes in weedy backgrounds will also not have an effect towards enhancing the weedy features in these populations.


Asunto(s)
Plantas Modificadas Genéticamente , Sorghum/genética , Germinación , Cruzamientos Genéticos , Sorghum/crecimiento & desarrollo , Vigor Híbrido , Hibridación Genética
5.
Proc Nutr Soc ; 74(4): 441-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25851095

RESUMEN

The focus of the review paper is to discuss how biotechnological innovations are opening new frontiers to mitigate nutrition in key agricultural crops with potential for large-scale health impact to people in Africa. The general objective of the Africa Biofortified Sorghum (ABS) project is to develop and deploy sorghum with enhanced pro-vitamin A to farmers and end-users in Africa to alleviate vitamin A-related micronutrient deficiency diseases. To achieve this objective the project technology development team has developed several promising high pro-vitamin A sorghum events. ABS 203 events are so far the most advanced and well-characterised lead events with about 12 µg ß-carotene/g tissue which would supply about 40-50 % of the daily recommended vitamin A at harvest. Through gene expression optimisation other events with higher amounts of pro-vitamin A, including ABS 214, ABS 235, ABS 239 with 25, 30-40, 40-50 µg ß-carotene/g tissue, respectively, have been developed. ABS 239 would provide twice recommended pro-vitamin A at harvest, 50-90 % after 3 months storage and 13-45 % after 6 months storage for children. Preliminary results of introgression of ABS pro-vitamin A traits into local sorghum varieties in target countries Nigeria and Kenya show stable introgression of ABS vitamin A into local farmer-preferred sorghums varieties. ABS gene Intellectual Property Rights and Freedom to Operate have been donated for use royalty free for Africa. Prior to the focus on the current target countries, the project was implemented by fourteen institutions in Africa and the USA. For the next 5 years, the project will complete ABS product development, complete regulatory science data package and apply for product deregulation in target African countries.


Asunto(s)
Agricultura , Dieta , Grano Comestible/química , Alimentos Modificados Genéticamente , Sorghum/química , Deficiencia de Vitamina A/prevención & control , beta Caroteno/administración & dosificación , Biotecnología , Productos Agrícolas , Humanos , Kenia , Nigeria , Valor Nutritivo , Sorghum/genética , beta Caroteno/genética
6.
Electron. j. biotechnol ; 12(2): 5-6, Apr. 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-551366

RESUMEN

This study was undertaken to characterize the alpha subgroup of the proteobacteria causing the huanglongbing (HLB) disease of citrus from three different ecological zones of Kenya namely the Lower highlands (LH2, LH3, 1800-1900 m above sea level); Upper midlands (UM3, UM4, 1390-1475m), Lower midlands (LM5, LM4, LM3 of 1290-1340-1390m), by isolation and sequencing DNA encoding the L10 and L12 ribosomal proteins and the intergenic region. A 7I6-basepair DNA fragment was amplified and sequenced and consisted of 536 basepairs of DNA encoding the L10 protein, 44 basepairs of DNA intergenic region and 136 basepairs of DNA that partially encodes the L12 protein. Sequences of rpL10/L12 protein genes from Kenyan strains were 98 percent and 81 percent similar to the South African 'Candidatus Liberibacter africanus strain Nelspruit' and the Asian 'Candidatus Liberibacter asiaticus' strains, respectively. The intergenic rDNA sequence of Kenyan strain from UM and LM showed 84 percent similarity with 'Candidatus L. africanus strain Nelspruit' and 50 percent similarity with 'Candidatus L. asiaticus' strain. However, the LH strain had an 11- basepairs deletion, while the LM4 had a 5-basepair deletion in the intergenic region compared to 'Candidatus L. africanus strain Nelspruit'. The L10 amino acid sequence was 100 percent homologous among HLB bacteria obtained from the agro-ecological zones in Kenya and the L10 protein sequence was also homologus to 'Candidatus L. africanus strain Nelspruit'. Nevertheless, the L10 amino acid sequence of 'Candidatus L. asiaticus' and the 'Candidatus L. africanus subsp. capensis' differed from the Kenyan strains by 18.36 percent and 11.82 percent, respectively. Phylogenetic analysis of both the L10/L12 rDNA sequences and the L10 amino acid sequences clustered the Kenyan strains of the 'Candidatus Liberibacter' species with members of alpha subdivision of proteobacteria.


Asunto(s)
ADN Ribosómico/agonistas , ADN Ribosómico/genética , Proteobacteria/enzimología , Proteobacteria/metabolismo , Proteínas Ribosómicas , Análisis de Secuencia de ADN/métodos , Análisis de Secuencia de ADN , Electroforesis en Gel de Agar , Kenia , Filogenia
7.
Phytochemistry ; 64(7): 1213-21, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14599519

RESUMEN

The objective of the study was to determine the patterns of expression of two photosynthetic genes rbcL and psbA, during chloroplast and chromoplast differentiation in fruit tissues of three Cucurbitae pepo L. cultivars: Early Prolific, Foodhook Zucchini and Bicolor Gourds. In two Early Prolific isogenic lines, YYBB and YYB+B+, the steady-state amounts of rbcL and psbA transcripts increased with fruit development upto 14 days post-pollination. The YYB+B+ line in which chloroplast differentiates into chromoplast at about pollination, did not show significantly higher amounts of both transcripts compared to YYBB, in which chromoplast develops early prior to pollination. In the Bicolor Gourds, in which the chromoplast and chloroplast containing tissues lie in juxtaposition on the same fruit, showed little differences in rbcL and psbA transcripts between the two tissues, if any the chromoplast containing tissue contained more of both transcripts than the chloroplast containing tissue. In Fordhook Zucchini fruits, where the chloroplast containing tissue developed early prior to pollination and was maintained, the steady-state amounts of rbcL transcripts increased to a maximum at 3 days post-pollination and levelled at 14 and 21 days post-pollination. In contrast, in Fordhook Zucchini fruits, the psbA transcript increased gradually up to 21 days post-pollination. In Fordhook Zucchini, the apparent ratios of psbA transcripts versus rbcL transcripts ranged from 2.5 to 3.9, at day 3 to 21 post-pollination, while in Bicolor Gourds were 2.9 and 4.5 at days 14 and 21 post-pollination. The two photosynthetic genes, psbA and rbcL were developmentally regulated and differentially expressed. However, their expression in chloroplast containing fruit tissues was not higher than in the chromoplast containing fruit tissues.


Asunto(s)
Cloroplastos/fisiología , Cucurbita/fisiología , Complejo de Proteína del Fotosistema II/biosíntesis , Plastidios/genética , Plastidios/fisiología , Ribulosa-Bifosfato Carboxilasa/biosíntesis , Northern Blotting , Cloroplastos/metabolismo , Cucurbita/genética , Cucurbita/metabolismo , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Fotosíntesis , Complejo de Proteína del Fotosistema II/genética , Hojas de la Planta/metabolismo , Plastidios/metabolismo , Polen , Reproducción , Ribulosa-Bifosfato Carboxilasa/genética , Factores de Tiempo , Transcripción Genética
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