Oxidative processes, such as oxidative phosphorylation indispensable for aerobic organisms to produce ATP via respiration, ironically produce highly active free radicals in the process: these radicals are thought to contribute to cancer, atherosclerosis, inflammation, hypertension, and diabetes [6].
The immune system is indispensable for multicellular organisms to cope with different pathogens such as bacteria, viruses or fungi.
Therefore, GNA1 is indispensable for the viability of organisms.
It is so far the only histone that has been shown to be indispensable for survival in many organisms and while only a single gene copy is present in invertebrates, two distinct gene copies exist in vertebrates [ 10].
With the exception of yeast, H2A.Z has been shown to be indispensable for survival in several model organisms including the ciliate protozoan Tetrahymena [ 71], Drosophila [ 72], Xenopus [ 73], and mice [ 74].
Essential genes are those indispensable for the survival of an organism and are thus considered as foundations of life.
The DEG curates a searchable list of "Essential genes [that] are those indispensable for the survival of an organism, and therefore are considered a foundation of life".
Another group from Tianjin University has built a database of essential genes (DEG), to record the currently available genes that are indispensable for the survival of an organism.
Identification of essential genes (i.e., the genes that are indispensable for the survival of an organism under specific conditions) helps in defining targets for new antimicrobial agent development [ 13].
The functional annotation of such domain families, whether commonly shared between or exclusive to genomes, bears significance since they are likely indispensable for the survival of the organism [ 4].
