In a groundbreaking study, researchers from Indiana University, Bloomington, have explored the evolutionary potential of cells with minimal genes. These are defined as the least number of genes required for an organism’s survival and reproduction. The research, which was recently published in the scientific journal ‘Nature’, provides insight into the adaptability and evolution of cells that only possess essential genes. In doing so, it challenges existing concepts of genetic flexibility and mutation rates.
Focusing on Synthetic Minimal-Cell Version of Mycoplasma Mycoides
The researchers focused their study on a synthetic minimal-cell version of Mycoplasma mycoides, a bacterial species known to cause respiratory diseases in goats and cattle. This minimal version only possesses 493 vital genes compared to its non-minimal strain, which has 901 genes. The study took place over a period of 300 days and found that Mycoplasma mycoides holds the record for the highest mutation rate of any cellular organism.
Minimal Essential Genes Adapt at Comparable Rates to Normal Cells
One of the key findings from this study is that cells with minimal essential genes can adapt and evolve at a similar rate to normal cells. Despite having less genetic material, the minimal cells demonstrated mutation rates that mirrored those of non-minimal cells. Genome minimization did not inhibit the rate of adaptation in minimal cells, dispelling previous notions about the effects of genetic reduction.
Implications for Synthetic Biology
This understanding of the evolution of minimal cells holds significant implications for fields such as synthetic biology. In this discipline, researchers utilize engineering principles to design organisms intended for use in medicine and fuel production. The study demonstrated that engineered cells are not static; they undergo evolution, providing valuable knowledge on how synthetic organisms might adapt when confronting the inevitable forces of evolution.
Definitions of Key Genetic Terms
Genes are segments of Deoxyribonucleic acid (DNA) responsible for coding specific proteins or functions, acting as the fundamental units of heredity. Gene mutation refers to changes in the DNA sequence of a gene, which potentially affect its function or expression. This can be caused by errors during DNA replication, radiation or chemical exposure, among other factors.
A genome represents an organism or virus’s complete set of genetic information. Genetic sequencing involves determining a DNA or RNA molecule’s order of nucleotides or bases (A, G, C, and T). Genome editing constitutes a form of genetic engineering where DNA is added, deleted, modified, or replaced within the genome of a living organism. Meanwhile, genetic modification involves changing an organism’s DNA, such as a bacterium, plant, or animal, by introducing DNA elements from another organism.
The Application of Genome Sequencing in Agriculture
The technique of genome sequencing has been in the news because of its potential application in agriculture. For instance, it can be used to identify genetic markers for disease resistance and drought tolerance in different crops. This technique is beneficial in reducing the time needed to develop new crop varieties and understanding host-pathogen relationships in crops.
In 2002, Chinese scientists decoded the rice genome, leading to the development of better rice varieties like Pusa Basmati-1 and Pusa Basmati-1121. Genome sequencing has also facilitated the production of transgenic varieties, including insect-resistant cotton, herbicide-tolerant soybean, and virus-resistant papaya. Besides, this technique can provide a thorough understanding of how microbes or viruses maintain themselves within host organisms at molecular, cellular, organism, or population level.
