Adaptive diversification

Shi P, Zhang 1, Yang H, Zhang YP. Adaptive diversification of 93. bitter taste receptor genes in Mammahan evolution. Mol. Biol. 

Shi P, Bielawski JP, Yang H, Zhang YP (2005) Adaptive diversification of vomeronasal receptor 1 genes in rodents. J Mol Evol 60 566-576... 

P.D.N Hebert, D.B. McWalter (1983), Cuticular pigmentation in Arctic Daphnia adaptive diversification of asexual lineages. Am. Nat., 122, 286-291. 

Life in the oceans differs in most respects from life on land. The most remarkable observation is that the oceans are poorer in species but richer in phyla with respect to land (Chapter 1.2). This finds no easy answer, however. Perhaps the reason for the larger number of species on land lies in a wider diversification of habitat and climate than in the sea, which required a great deal of adaptation, accompanied by speciation. In these affairs, coevolution of plants with insects was a major trigger of biodiversity. 

Spratt BG, Hanage WP, Feil EJ (2001) The relative contributions of recombination and point mutation to the diversification of bacterial clones. Curr Opin Microbiol 4 602-606 Stepkowski T, Legocki AB (2001) Reduction of bacterial genome size and expansion resulting from obligate intracellular lifestyle and adaptation to soil habitat. Acta Biochim Polonica 48 367-381... 

As an example of scaffold synthesis rather than decoration, we adapted the Lacey-Dieckmann synthesis of tetramic acids to a combinatorial strategy (Figure 6). The overall sequence is only three steps, and all the three reaction inputs involve readily available building blocks amino acids, aldehydes, and carboxylic acids. We published both solution- and solid-phase protocols, and this was followed soon thereafter by similar reports from industrial groups. Clearly, the ability to access this heterocycle with ample room for diversification was highly attractive, and each of us had independently developed this idea. 

Hashiguchi Y, Nishida M (2007) Evolution of trace amine associated receptor (TAAR) gene family in vertebrates lineage-specific expansions and degradations of a second class of vertebrate chemosensory receptors expressed in the olfactory epithelium. Mol Biol Evol 24 2099-2107 Hashiguchi Y, Furuta Y, Kawahara R, Nishida M (2007) Diversification and adaptive evolution of putative sweet taste receptors in threespine stickleback. Gene 396 170-179 Hemess MS, Gilbertson TA (1999) Cellular mechanisms of taste transduction. Annu Rev Physiol 61 873-900... 

Such inherencies and analogs suggest that the motors of adaptation and ecological diversification make the emergence of complex biological systems, say an eye seeing a rose garden, probable, and perhaps even inevitable. The basic similarity... 

Antigen presentation can be viewed as an adaptation of an older cell-cell recognition function into two separate systems which identify distinct classes of MHC molecules. The first system has evolved to monitor and ensure the integrity of cell surface structures and consists of MHC molecules expressed on most cell types and mainly recognized by cytotoxic T cells (class 1 molecules). The second system has evolved to mediate cell-cell interactions in the immune response and consists of MHC molecules mostly expressed on macrophages and B cells and mainly recognized by regulatory T cells (class 11 molecules). The functional diversification between class I and class 11 molecules is reflected in substantial structural differences (see below). 

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