Ultrastructural identity
chrysophyte and a typical haptophyte
Ultrastructural identity is a concept in
electron microscopy
.
The concept emerged following the application of electron microscopy to protists.
Protists
Early ultrastructural studies revealed that many previously accepted groupings of protists based on
taxopodids.[5]
A critical advance was made by British
Protozoologists Brugerolle and Patterson were the first to use the term 'ultrastructural identity' in discussing the differences between ciliates and a lookalike protist, Stephanopogon.[7] Patterson later applied the concept to all eukaryotes, classifying their diversity into 71 types, each without clear sister group affinities.[8]
A further 200 or so genera that had not yet been studied by electron microscopy were listed.
The catalog of groups with distinctive ultrastructural identities has been used as a base-line for efforts to build a stable tree for all eukaryotes using molecular data.[9]
An indirect benefit of the focus on ultrastructural characters was that it allowed
ciliates were likely related.[10] They, and some related flagellates, were shown to share a distinctive system of sacs or alveoli under the cell membrane, and because of this were given the name Alveolates. Similarly, tripartite tubular hairs attached to various algae, fungi and protozoa provided the synapomorphy for the 'stramenopiles' (straw-hairs)[11] A distinctive flagellar root system that caused grooving on their cell surface was treated as a synapomorphy of the excavate flagellates.[12]
References
- ^ Bardele, C. F. 1972. Cell cycle, morphogenesis, and ultrastructure in the pseudoheliozoan Clathrulina elegans. Zeitschrift für Zellforschung 130:219–242
- ^ Bardele, C. F. 1975 The fine structure of the centrohelidian heliozoan Heterophrys marina. Cell Tiss. Res, 161: 85-102
- ^ Bardele, C. F. 1977. Comparative study of axopodial microtubule patterns and possible mechanisms of pattern control in the centrohelidian heliozoa Acanthocystis, Raphidiophrys and Heterophrys. J. Cell Sci. 25, 205-23
- ^ Bardele, C. F. 1977. Organization and control of microtubule pattern in centrohelidian heliozoa. J. Protozool. 24, 9-14
- ^ Smith, R. McK., and Patterson, D.J. 1986. Analyses of heliozoan interrelationships: an example of the potentials and limitations of ultrastructural approaches to the study of protistan phylogeny. Proceedings of the Royal Society of London. Series B, Biological Sciences, 227: 325-366
- ^ Hibberd, D. J. 1976. The ultrastructure and taxonomy of the Chrysophyceae and Prymnesiophyceae (Haptophyceae): a survey with some new observations on the ultra-structure of the Chrysophyceae. Botanical Journal of the Linnean Society 72:55–80
- ^ Patterson, D. J. & Brugerolle, G. 1988. The ultrastructural identity of Stephanopogon apogon and the relatedness of the genus to other kinds of protists. Europ. J. Protistol. 23: 279-290.
- ^ Patterson, D. J. 1999. The diversity of eukaryotes. American Naturalist 154: S96-124
- ^ Parfrey, L. W., Grant, J., Tekle, Y. I., Lasek-Nesselquist, E., Morrison, H. G., Sogin, M. L., Patterson, D. J., & Katz, L. A. (2010). Broadly sampled multigene analyses yield a well-resolved eukaryotic tree of life. Systematic biology, 59(5), 518–533. https://doi.org/10.1093/sysbio/syq037
- ^ Gajadhar, A. A., W. C. Marquardt, R. Hall, J. Gunderson, E. V. Ariztia-Carmona, and M. L. Sogin. 1991. Ribosomal RNA sequences of Sarcocystis muris, Theileria annulata and Crypthecodinium cohnii reveal evolutionary relationships among apicomplexans, dinoflagellates, and ciliates. Molecular and Biochemical Parasitology 45: 147–154
- ^ Patterson, D. J. 1989. Stramenopiles: chromophytes from a protistological perspective. In: Green, J.C., Leadbeater, B.S.C. & Diver, W. L. 1989. The chromophyte algae: problems and perspectives. Clarendon Press, Oxford. 357-379.
- ^ Simpson A. G. B. & Patterson, D. J. 1999. The ultrastructure of Carpediemonas membranifera: (Eukaryota), with reference to the 'excavate hypothesis'. European Journal of Protistology 35: 353-370