Survival Mechanisms to Selective Pressures and Implications

Organisms have evolved a spectrum of strategies that facilitate survival in the face of adverse environmental conditions. In order to make full use of the unfavorable resources of nature, human beings usually impose selective pressures to breed phenotypic traits that can survive in adverse environments. Animals are frequently under attack by biotic stress, such as bacterial and viral infections, while plants are more often subjected to abiotic stress, including high salinity, drought, and cold. In response to these diverse stresses, animals and plants initiate wide-ranging changes in gene expression by altering regulation of transcriptional and post-transcriptional activities. Recent studies have identified a number of key responsive components that promote survival of animals and plants in response to biotic and abiotic stresses. Importantly, with recent developments in genome-editing technology based on the CRISPR/Cas9 system, manipulation of genetic elements to generate stress-resistant animals and plants has become both feasible and cost-effective. Herein, we review important mechanisms that govern the response of organisms to biotic and abiotic stresses with the aim of applying our understanding to the agriculture and animal husbandry industries.