Document Type
Article
Publication Date
10-1-2017
Publication Title
European Journal of Protistology
Abstract
Genome structure and nuclear organization have been intensely studied in model ciliates such as Tetrahymena and Paramecium, yet few studies have focused on nuclear features of other ciliate clades including the class Karyorelictea. In most ciliates, both the somatic macronuclei and germline micronuclei divide during cell division and macronuclear development only occurs after conjugation. However, the macronuclei of Karyorelictea are non-dividing (i.e. division minus (Div−)) and develop anew from micronuclei during each asexual division. As macronuclei age within Karyorelictea, they undergo changes in morphology and DNA content until they are eventually degraded and replaced by newly developed macronuclei. No less than two macronuclei and one micronucleus are present in karyorelictid species, which suggests that a mature macronucleus 1) might be needed to sustain the cell while a new macronucleus is developing and 2) likely plays a role in guiding the development of the new macronucleus. Here we use a phylogenetic framework to compile information on the morphology and development of nuclei in Karyorelictea, largely relying on the work of Dr. Igor Raikov (1932–1998). We synthesize data to speculate on the functional implications of key features of Karyorelictea including the presence of at least two macronuclei in each cell and the inability for macronuclei to divide.
Keywords
Karyorelictea, Non-dividing macronuclei, Nuclear architecture
Volume
61
First Page
399
Last Page
408
DOI
10.1016/j.ejop.2017.05.002
ISSN
09324739
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Rights
Licensed to Smith College and distributed CC-BY under the Smith College Faculty Open Access Policy.
Recommended Citation
Yan, Ying; Rogers, Anna J.; Gao, Feng; and Katz, Laura A., "Unusual Features of Non-Dividing Somatic Macronuclei in the Ciliate Class Karyorelictea" (2017). Biological Sciences: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/bio_facpubs/94
Comments
Peer reviewed accepted manuscript.