Premium
Development in Electrofused Conjugants of Tetrahymena thermophila
Author(s) -
COLE ERIC S.,
VIRTUE MARK A.,
STUART KATHLEEN R.
Publication year - 2001
Publication title -
journal of eukaryotic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 1066-5234
DOI - 10.1111/j.1550-7408.2001.tb00314.x
Subject(s) - biology , ploidy , tetrahymena , zygote , meiosis , mating type , genetics , mitosis , cytokinesis , mating , cell division , mating of yeast , sexual reproduction , microbiology and biotechnology , embryo , cell , embryogenesis , gene
. Electric shock can create parabiotic fusions of living Tetrahymena cells. In this study, cells were mated and successful pairs were electrofused with either vegetatively growing cells or other mating pairs. In particular, we electrofused pairs from normal [diploid × diploid] matings with vegetatively dividing cells in G‐ or M‐phase of the cell cycle. We also fused [diploid × diploid] conjugants with mating pairs involving an aneuploid partner [diploid דstar”], which typically undergo an abortive conjugal pathway termed genomic exclusion. Using such parabiotic fusions we identified and characterized two developmentally critical landmarks: I) the “abort” signal, which is initiated in pairs with nuclear defects (this first becomes evident soon after the completion of Meiosis I or the beginning of Meiosis II); and 2) the “terminal commitment point”, a developmental stage in normal [diploid × diploid] pairs after which conjugation no longer responds to a parabiotically transmitted abort signal (this correlates with the onset of the second postzygotic nuclear division). Finally we demonstrate that a conjugal‐arrest‐activity varies with the vegetative cell cycle, reaching its highest level of activity during M‐phase and dropping just after cytokinesis.