Phenotypic characters

Murata, K., Fukuda, Y., Shimosaka, M., Watanabe, K., Saikusa, T., and Kimura, A., Phenotype character of the methylglyoxal resistance gene in Saccharomyces cerevisiae Expression in Escherichia coli and application to breeding wild-type yeast strains, Appl Environ Microbiol, 50 (5), 1200-1207,1985. 

Sjamsuridzal W, Tajiri Y, Nishida H, Thuan TB, Kawasaki H, Hirata A, Yokota A, Sugiyama J Evolutionary relationships of members of the genera Taphrina, Protomyces, Schizosaccharomyces, and related taxa within the archiascomycetes Integrated analysis of genotypic and phenotypic characters. Mycoscience 1997 38 267-280. 

There is a wide range of variations that may occur within a coconut palm colony with regard to phenotype characteristics such as color, size and shape of nuts, and shape and symmetry of crown, among others. In some isolated localities, colonies of coconut palm develop well-defined and uniform phenotypic characters arising from generations of namral selection. 

The first example is the comparison of phenotypes and genotypes of the seedless vascular plants listed below (Cycas is listed as an outgroup).2 It contains 51 species mostly in Pterophyta. For these species we have both DNA sequence and phenotypic character tables [13,14]. The phenotypic character table contains 77 characters that take integer values ranging from 0 to 5. DNA sequences (rbcL) have 1206 bases. The dissimilarity based on phenotypic characters is defined as... 

Figure 5. 2D embedding of some seedless vascular plants based on phenotypic characters. 

The second example is the analysis of a group including Bryophyta and Chlorophyta.3 For these species, we have both DNA sequence and phenotype character tables [15,16]. The number of species included is 59, for which 110 phenotypic characters are listed. Each phenotypic character has five evaluation letters from a to e. Some species take more than one value for some characters. Although the definition of 8y is similar to that used in the preceding subsection, it is modified as... 

It is of course too early to conclude anything definite from these preliminary attempts, but they may suggest that similar phenotypic characters are associated with similar genetic structures only among phylogenetically closely related organisms. 

Varieties of H. perforatum with broad (var. perforatum) and narrow (var. angustifolium) sized leaves have been in fact recognized, together with plant populations with intermediate (var. microphyllum) phenotypic characters. 

The availability of mutations with a different degree of ABA deficiency is thus an important tool to test the relevance of ABA concentration on development. The three mutations of the aba locus in A rabidopsis indicate a positive interaction between the ABA concentration and the degree of deviation of all but one of the phenotype characters (Table 2). Seed development is the exception. The experiments with the aba abiS recombinant (described above) showed that the responsiveness of seed development to ABA is so high that endogenous ABA concentration during seed development was never limiting. However, in other responses a reduction of ABA concentration below wild-type levels does limit normal development. 

Cottrell, M. and Kock, J.L.F. (1989) The yeast family Lipomycetaceae and the genus Myxozyma 1. A historical account of its delimitation and 2. The taxonomic relevance of cellular long-chain fatty acid composition and other phenotypic characters. Syst. Appl Microbiol. 12, 291-305. 

Two other terms might need an explanation, too incomplete penetrance refers to the phenomenon that genes which ordinarily behave as dominants occasionally may not manifest at all in a few known heterozygotes. Variable expressivity, on the other hand, imphes that individuals heterozygous for the same gene, may display the phenotypical character to a variable degree. 

Phenotypes include morphological, physiological, biochemical and immunological characters as a whole and the composition of certain cellular components. Certain phenotypic characters appear to vary in a given strain—for example, the assimilation of certain sugars. Certain strains having different phenotypes but belonging to the same species are atypical strains. 

Since the beginning of microbiology, the identification of bacteria has been based on their phenotypic characters (Section 4.3.2). Besides by its morphology, which gives little information, a strain is identified essentially by the substrates and products of its metabolism. When more discriminating analytical methods appeared, the chemical composition of microorganisms (fatty acids and proteins. Section 4.3.8) also participated in their identification. 

Identification by phenotypic analysis of clones isolated in wine often poses two kinds of problems. First, these clones are difficult to multiply in laboratory conditions. Numerous sub-cultures are needed to obtain a sufficient biomass to carry out all of the tests. For the same reasons, the response to biochemical tests in the API tests (Section 4.3.2) can be ambiguous. The change of color of the indicator is not distinct if the strain does not multiply sufficiently in the microtube. Second, the phenotypic character, such as the assimilation of a... 

Tables 4.4 and 4.5 summarize the phenotypic characters used to determine genus and species. Most of the strains for each species have...

Uryvaeva, I. V. Tsitrin, E. B. Gorodetsky, S. I. Tsvetkova, I. A. Delone, G. V. Gulyaev, D. V. Khrushchov, N. G. The phenotypic characters of the stem cells in hepatocjdes during liver regeneration the expression of the Bcrpl/Abcg2 membrane transporter and the Hoechst 33342 export. Dokl. Biol. Sci. 2004, 398, 413-416. 

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