Document Type
Article
Language
eng
Format of Original
14 p.
Publication Date
7-15-2006
Publisher
Elsevier
Source Publication
Developmental Biology
Source ISSN
0012-1606
Abstract
The ciliated protozoan Tetrahymena has two nuclei: a germ line micronucleus and a somatic macronucleus. The transcriptionally active macronucleus has about 50 copies of each chromosome. At sexual reproduction (conjugation), the parental macronucleus is degraded and new macronucleus develops from a mitotic product of the zygotic micronucleus. Development of the macronucleus involves massive genome remodeling, including deletion of about 6000 specific internal eliminated sequences (IES) and multiple rounds of DNA replication. A gene encoding a putative signal transduction receptor, ASI2, (anlagen stage induced 2) is up-regulated during development of the new macronuclei (anlagen). Macronuclear ASI2 is nonessential for vegetative growth. Homozygous ASI2 germ line knockout cells with wild type parental macronuclei proceed through mating but arrest at late macronuclear anlagen development and die before the first post-conjugation fission. IES elimination occurs in these cells. Two rounds of postzygotic DNA replication occur normally in progeny of ASI2 germ line knockouts, but endoreduplication of the macronuclear genome is arrested. The germ line ASI2 null phenotype is rescued in a mating of a knockout strain with wild type cells.
Creative Commons License
This work is licensed under a Creative Commons Attribution-No Derivative Works 4.0 International License.
Recommended Citation
Li, Shuqiang; Yin, Lihui; Cole, Eric S.; Udani, Rupa A.; and Karrer, Kathleen M., "Progeny of Germ Line Knockouts of ASI2, a Gene Encoding a Putative Signal Transduction Receptor in Tetrahymena Thermophila, Fail to Make the Transition from Sexual Reproduction to Vegetative Growth" (2006). Biological Sciences Faculty Research and Publications. 12.
https://epublications.marquette.edu/bio_fac/12
Comments
Accepted version. Developmental Biology, Vol. 295, No. 2 (July 2006): 633-646. DOI. Published under Creative Commons License Attribution-Noncommercial-NoDerivs 4.0.
NOTICE: this is the author’s version of a work that was accepted for publication in Developmental Biology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Developmental Biology, VOL 295, ISSUE 2, July 15, 2006. DOI.