Ingestion of Fluorescently Labeled Viruses by Brachionus Plicatilis (Rotifera)
Submission Type
Event
Expected Graduation Date
2015
Location
Center for Natural Sciences, Illinois Wesleyan University
Start Date
4-18-2015 9:00 AM
End Date
4-18-2015 10:00 AM
Disciplines
Biology
Abstract
Rotifers are aquatic suspension-feeding invertebrates that use cilia to produce water currents for swimming and capturing particles. They can consume a variety of different sized foods ranging from protozoans (300 µm) through algae (2-10 µm) to bacteria (0.5-1 µm). In marine and freshwater environments where rotifers are found, viruses (0.03-0.2 µm) are the most abundant biological particle (107 viruses / mL). Although previous studies have shown that single-celled flagellates and ciliates ingest viruses, it is not known if rotifers can also consume viruses. We examined the ingestion of viruses by the brackish-water rotifer Brachionus plicatilis. Rotifers were incubated (dark, 20 ºC) in seawater with viruses (108 viruses / mL) that were labeled with the fluorescent molecule 5-(4, 6 dichlorotrizinyl) aminofluorescein (DTAF), in a 2 µg / mL solution of DTAF, and with no additions (control) for periods of time that ranged between 1 hour and 24 hours. After incubation the rotifers were fixed and the presence and distribution of the fluorescence stain was detected using fluorescent microscopy (EX 450-490 nm, EM ≥ 520 nm). When incubated with DTAF-labeled viruses for 12 and 24 hours, the fluorescence was restricted to the lumen of the gut and the intensity of the fluorescence increased as the exposure time increased. After a 1-hour incubation with DTAF, the fluorescence in rotifers was present throughout their body and the intensity of DTAF increased with longer exposure times. No fluorescence was detected in the control animals that were not exposed to the fluorescent label. These results indicate that Brachionus plicatilis can ingest viruses and that these abundant particles represent a previously unknown food source for rotifers.
Ingestion of Fluorescently Labeled Viruses by Brachionus Plicatilis (Rotifera)
Center for Natural Sciences, Illinois Wesleyan University
Rotifers are aquatic suspension-feeding invertebrates that use cilia to produce water currents for swimming and capturing particles. They can consume a variety of different sized foods ranging from protozoans (300 µm) through algae (2-10 µm) to bacteria (0.5-1 µm). In marine and freshwater environments where rotifers are found, viruses (0.03-0.2 µm) are the most abundant biological particle (107 viruses / mL). Although previous studies have shown that single-celled flagellates and ciliates ingest viruses, it is not known if rotifers can also consume viruses. We examined the ingestion of viruses by the brackish-water rotifer Brachionus plicatilis. Rotifers were incubated (dark, 20 ºC) in seawater with viruses (108 viruses / mL) that were labeled with the fluorescent molecule 5-(4, 6 dichlorotrizinyl) aminofluorescein (DTAF), in a 2 µg / mL solution of DTAF, and with no additions (control) for periods of time that ranged between 1 hour and 24 hours. After incubation the rotifers were fixed and the presence and distribution of the fluorescence stain was detected using fluorescent microscopy (EX 450-490 nm, EM ≥ 520 nm). When incubated with DTAF-labeled viruses for 12 and 24 hours, the fluorescence was restricted to the lumen of the gut and the intensity of the fluorescence increased as the exposure time increased. After a 1-hour incubation with DTAF, the fluorescence in rotifers was present throughout their body and the intensity of DTAF increased with longer exposure times. No fluorescence was detected in the control animals that were not exposed to the fluorescent label. These results indicate that Brachionus plicatilis can ingest viruses and that these abundant particles represent a previously unknown food source for rotifers.