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A single gene may be sufficient to induce asexual reproduction of plants

Researchers at Howard Hughes Medical Institute (HHMI) have reported in the journal 'Nature' of the progress to make sexually reproducing plants to reproduce asexually. This would mean, reducing the need to conduct cross mating to get, generation after generation, seeds that are robust and resilient. The discovery could have important implications for farming, especially in economic terms.

A.R. | 9 March 2010


Photo: Jean Philippe Vielle-Calzada
During sexual reproduction, many of the characteristics of robustness and resilience in the seeds disappear. Thus, year after year, farmers must purchase fresh seeds produced especially, which causes a considered increase in costs. Plants with asexual reproduction, such as dandelions and poplars, evade this issue, since they always produces genetically identical daughter plants.


Jean-Philippe Vielle-Calzada, from the Center for Research and Advanced Studies of the National Polytechnic Institute in Irapuato (Mexico) has been trying over decade to develop an asexual seed as well as studying apomixis, a specific type of asexual reproduction, through which nearly 350 species of plants produce viable seeds without the need for the merger between sperm and egg. In apomixis, the reproductive cells retain all the genetic material of chromosomes, instead of losing half of the genes during meiosis, as occurs in sexual reproduction. Thus, Vielle-Calzada tried to induce apomixis in a sexually reproducing plant, Arabidopsis thaliana.

In recent research, the same investigator, with scientists from Mexico, France and the United States have focused on Arabidopsis reproductive structure, the egg. Each egg produces only one tiny female gamete, which, when fertilized, becomes a seed. The team performed a genetic screen to identify genes that are active in the egg, with the intention of detecting protein gene products that control reproduction.


In recent research, the same investigator, together with scientists from Mexico, France and the United States have focused on the reproductive structure of Arabidopsis, the egg. Each minute egg produces only one tiny female gamete, which, when fertilized, becomes a seed. The team performed a genetic search to identify the genes that are active in the egg, with the intention of detecting protein that control the genetic products of the reproduction.

The researchers obtained a number of interesting genes, but one in particular, Argonauta 9, got their attention. For two reasons: they have an important role in controlling gene products and have never before been observed in reproductive cells of Arabidopsis. After mutating the gene, rather than producing a single gamete, most of the eggs produced a number of abnormal gametes. Instead of having half the chromosomes of the species, they had all the genetic material, suggesting that they had not undergone meiosis. Furthermore, it shows that in all probability, Argonauta 9 prevents the initiation of apomixis.

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bruss acevedo san cerdin 25/09/2010
la chupo rico y gratis :) llamenme al 2721645 chupenla perras qlias

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