Biological and molecular characterization of cellular differentiation in Tetrahymena vorax: A potential biocontrol protozoan

• Published in: Journal of basic microbiology Vol. 40; no. 5-6; pp. 351 - 361
• Main Authors: Green, Marino M., LeBoeuf, Robert D., Churchill, Perry F.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag Berlin GmbH 01.01.2000; WILEY‐VCH Verlag Berlin GmbH
• Subjects: Amino Acid Sequence; Animals; Base Sequence; DNA, Complementary; Gene Expression Regulation, Developmental; Nucleic Acid Hybridization - methods; Oligonucleotides, Antisense - metabolism; Pest Control, Biological; Protozoan Proteins - chemistry; Protozoan Proteins - genetics; Protozoan Proteins - metabolism; RNA, Messenger - metabolism; Sequence Analysis, DNA; Tetrahymena - genetics; Tetrahymena - physiology; Tetrahymena vorax; Transcription, Genetic
• ISSN: 0233-111X; 1521-4028
• DOI: 10.1002/1521-4028(200012)40:5/6<351::AID-JOBM351>3.0.CO;2-Q

Tetrahymena vorax (T. vorax) is an indigenous fresh water protozoan with the natural biological potential to maintain a specific aquatic microbial flora by ingesting and eliminating specific microorganism. To investigate the molecular mechanisms controlling Tetrahymena vorax (T. vorax) cellular differentiation from a small‐mouth vegetative cell to a voracious large‐mouth carnivore capable of ingesting prey ciliates and bacteria from aquatic environments, we use DNA subtraction and gene discovery techniques to identify and isolate T. vorax differentiation‐specific genes. The physiological necessity for one newly discovered gene, SUBII‐TG, was determined in vivo using an antisense oligonucleotide directed against the 5′ SUBII‐TG DNA sequence. The barriers to delivering antisense oligonucleotides to the cytoplasm of T. vorax were circumvented by employing a new but simple procedure of processing the oligonucleotide with the differentiation stimulus, stomatin. In these studies, the antisense oligonucleotide down‐regulated SUBII‐TG mRNA expression, and blocked differentiation and ingestion of prey ciliates. The ability to down‐regulate SUBII‐TG ex‐pression with the antisense oligonucleotide suggests that the molecular mechanisms controlling the natural biological activities of T. vorax can be manipulated to further study its cellular differentiation and potential as a biocontrol microorganism.