| Contributors | Affiliation | Role |
|---|---|---|
| Lopanik, Nicole | Georgia Institute of Technology (GA Tech) | Principal Investigator |
| Lim-Fong, Grace | Georgia Institute of Technology (GA Tech) | Co-Principal Investigator |
| Rauch, Shannon | Woods Hole Oceanographic Institution (WHOI BCO-DMO) | BCO-DMO Data Manager |
B. neritina colonies were collected by hand off the sides of floating docks around Morehead City, NC, and Oyster, VA. Larvae from individual colonies were collected and settled into 10 mL of filtered seawater with (treated) or without (control) 100 ug/mL of gentamicin as described in Lopanik et al. 2004. Larvae were allowed to settle overnight. The control and treated seawater was changed the next morning for the next 3 days. The plates were transported to Georgia Tech where they were placed in 2.5 gallon tanks with artificial seawater maintained in environmental chambers at 16°C and 22°C either with or without 2 invertebrate predators (tunicates). They were fed ad libitum an artificial diet of the phytoplankton Rhodomonas lens for approximately three months. After a 5 week period, the size of the colonies was measured by counting the number of zooids in each colony. Samples of larvae, juvenile and the grown colonies were placed in RNAlater for symbiont quantification analysis by quantitative PCR. After 13 and 25 weeks, the size of the colonies was measured by counting the number of bifurcations, and colonies were placed into RNAlater for symbiont quantification. Data was analyzed using IBM SPSS Statistics 24.
BCO-DMO Processing: modified parameter names to conform with BCO-DMO naming conventions (replaced spaces with underscores, replaced "+" with "plus", replaced "-" with "minus", replaced "+SE" with "SE").
| File |
|---|
mesocosm_winter_17.csv (Comma Separated Values (.csv), 1.94 KB) MD5:c9504246a122163cbc5122bd51cc3502 Primary data file for dataset ID 748480 |
| Parameter | Description | Units |
| Tank_Tmt | Mesocosm treatment (Cold or Warm, With or without predator) | unitless |
| Splus_Cont_Avg_5w | Avg size in zooids of S+ cont colonies after 5 weeks | unitless |
| Splus_Cont_SE_5w | Std. error of avg. size in S+ cont colonies | unitless |
| Splus_Cont_N_5w | Number of colonies in which size was measured | unitless |
| Splus_Ant_Avg_5w | Avg size in zooids S+ antibiotic treated colonies after 5 weeks | unitless |
| Splus_Ant_SE_5w | Std. error of avg. size in S+ antibiotic treated colonies | unitless |
| Splus_Ant_N_5w | Number of colonies in which size was measured | unitless |
| Nplus_Cont_Avg_5w | Avg size in zooids of N+ cont colonies after 5 weeks | unitless |
| Nplus_Cont_SE_52 | Std. error of avg. size in N+ cont colonies | unitless |
| Nplus_Cont_N_5w | Number of colonies in which size was measured | unitless |
| Nplus_Ant_Avg_5w | Avg size in zooids of N+ antibiotic treated colonies after 5 weeks | unitless |
| Nplus_Ant_SE_5w | Std. error of avg. size in N+ antibiotic treated colonies after N/A | unitless |
| Nplus_Ant_N_5w | Number of colonies in which size was measured | unitless |
| Nminus_Cont_Avg_5w | Avg size in zooids of N- cont colonies after 5 weeks | unitless |
| Nminus_Cont_SE_5w | Std. error of avg. size in N- cont colonies | unitless |
| Nminus_Cont_N_5w | Number of colonies in which size was measured | unitless |
| Nminus_Ant_Avg_5w | Avg size in zooids of N- antibiotic treated colonies after 5 weeks | unitless |
| Nminus_Ant_SE_5w | Std. error of avg. size in N- antibiotic treated colonies | unitless |
| Nminus_Ant_N_5w | Number of colonies in which size was measured | unitless |
| Splus_Cont_Avg_13w | Avg size in bifurcations of S+ cont colonies after 13 weeks N/A | unitless |
| Splus_Cont_SE_13W | Std. error of avg. size in S+ cont colonies | unitless |
| Splus_Cont_N_13w | Number of colonies in which size was measured | unitless |
| Splus_Ant_Avg_13w | Avg size in bifurcs S+ antibiotic treated colonies after 13 weeks | unitless |
| Splus_Ant_SE_13w | Std. error of avg. size in S+ antibiotic treated colonies | unitless |
| Splus_Ant_N_13w | Number of colonies in which size was measured | unitless |
| Nplus_Cont_Avg_13w | Avg size in bifurcs of N+ cont colonies after 13 weeks | unitless |
| Nplus_Cont_SE_13w | Std. error of avg. size in N+ cont colonies | unitless |
| Nplus_Cont_N_13w | Number of colonies in which size was measured | unitless |
| Nplus_Ant_Avg_13w | Avg size in bifurcs of N+ antibiotic treated colonies after 13 weeks N/A | unitless |
| Nplus_Ant_SE_13w | Std. error of avg. size in N+ antibiotic treated colonies | unitless |
| Nplus_Ant_N_13w | Number of colonies in which size was measured | unitless |
| Nminus_Cont_Avg_13w | Avg size in bifurcs of N+ cont colonies after 13 weeks | unitless |
| Nminus_Cont_SE_13w | Std. error of avg. size in N+ cont colonies | unitless |
| Nminus_Cont_N_13w | Number of colonies in which size was measured | unitless |
| Nminus_Ant_Avg_13w | Avg size in bifurcs of N+ antibiotic treated colonies after 13 weeks N/A | unitless |
| Nminus_Ant_SE_13w | Std. error of avg. size in N+ antibiotic treated colonies | unitless |
| Nminus_Ant_N_13w | Number of colonies in which size was measured | unitless |
| Splus_Cont_Avg_25w | Avg size in bifurcations of S+ cont colonies after 25 weeks N/A | unitless |
| Splus_Cont_SE_25w | Std. error of avg. size in S+ cont colonies | unitless |
| Splus_Cont_N_25w | Number of colonies in which size was measured | unitless |
| Splus_Ant_Avg_25w | Avg size in bifurcs S+ antibiotic treated colonies after 25 weeks | unitless |
| Splus_Ant_SE_25W | Std. error of avg. size in S+ antibiotic treated colonies | unitless |
| Splus_Ant_N_25w | Number of colonies in which size was measured | unitless |
| Nplus_Cont_Avg_25w | Avg size in bifurcs of N+ cont colonies after 25 weeks | unitless |
| Nplus_Cont_SE_25w | Std. error of avg. size in N+ cont colonies | unitless |
| Nplus_Cont_N_25w | Number of colonies in which size was measured | unitless |
| Nplus_Ant_Avg_25w | Avg size in bifurcs of N+ antibiotic treated colonies after 25 weeks N/A | unitless |
| Nplus_Ant_SE_25w | Std. error of avg. size in N+ antibiotic treated colonies | unitless |
| Nplus_Ant_N_25w | Number of colonies in which size was measured | unitless |
| Nminus_Cont_Avg_25w | Avg size in bifurcs of N+ cont colonies after 25 weeks | unitless |
| Nminus_Cont_SE_25w | Std. error of avg. size in N+ cont colonies | unitless |
| Nminus_Cont_N_25w | Number of colonies in which size was measured | unitless |
| Nminus_Ant_Avg_25w | Avg size in bifurcs of N+ antibiotic treated colonies after 25 weeks N/A | unitless |
| Nminus_Ant_SE_25w | Std. error of avg. size in N+ antibiotic treated colonies | unitless |
| Nminus_Ant_N_25w | Number of colonies in which size was measured | unitless |
| Dataset-specific Instrument Name | Leica stereomicroscope |
| Generic Instrument Name | Microscope - Optical |
| Dataset-specific Description | A Leica stereomicroscope was used while counting the number of colony bifurcations. |
| Generic Instrument Description | Instruments that generate enlarged images of samples using the phenomena of reflection and absorption of visible light. Includes conventional and inverted instruments. Also called a "light microscope". |
| Dataset-specific Instrument Name | tank |
| Generic Instrument Name | Aquarium |
| Generic Instrument Description | Aquarium - a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept |
| Dataset-specific Instrument Name | quantitative PCR |
| Generic Instrument Name | qPCR Thermal Cycler |
| Generic Instrument Description | An instrument for quantitative polymerase chain reaction (qPCR), also known as real-time polymerase chain reaction (Real-Time PCR). |
Recent research has shown that microorganisms can be very important to their eukaryotic hosts, by providing nutrition or contributing to host defense against enemies, such as pathogens or predators. In many cases, however, hosting a bacterial symbiont imposes a physiological cost on the host organism, resulting in reduced growth or reproduction in the presence of the symbiont. Further, these costs may be more pronounced in some habitats than others, causing natural selection to act in eliminating symbiont-containing hosts from the population. In this project, the investigators are studying the relationship between the marine bryozoan invertebrate, Bugula neritina, and its uncultured symbiont. The symbiont produces natural products with activity against cancer, Alzheimer's disease, and HIV. Interestingly, these compounds also are distasteful and protect larvae from predators, indicating that this symbiotic relationship is defensive in nature. Along the East Coast of the US, the investigators have found a much higher proportion of individuals that have the defensive symbiont at lower latitudes, while the symbiont is absent in individuals collected at higher latitudes. This pattern is consistent with the theory that higher predation pressure exists at lower latitudes. Other environmental factors, such as temperature, can also vary over a wide geographical area, and may also play a role in influencing the relationship. In this project, the investigators will evaluate the ecological and environmental parameters that influence the distribution of a defensive symbiont, including predation pressure and temperature. Defensive symbionts represent another level of ecological complexity, and likely play an important role in structuring marine communities. This study will provide insight into how environmental factors can influence host-symbiont interactions and drive partner co-evolution. Furthermore, the bioactive products have pharmaceutical potential, and understanding how environmental factors influence the relationship between B. neritina and its symbiont may improve bioprospecting for novel compounds that could be developed into drugs.
In this research, the investigators will determine the ecological and environmental parameters that influence the distribution of a defensive symbiont in the marine bryozoan, Bugula neritina. The goal of this research is to determine the mechanism that results in the defensive endosymbiont being restricted to hosts that inhabit lower latitudes. This pattern of symbiont distribution could be the result of differing levels of costs and benefits at different latitudes: where predation pressure is low, the costs of hosting the symbiont outweigh the benefits, and aposymbiotic individuals outcompete their symbiotic conspecifics. In areas of higher predation, the defensive benefit outweighs the cost, and symbiotic individuals have higher survival rates than their undefended, aposymbiotic conspecifics. An alternative, but not mutually exclusive hypothesis, is that symbiont growth is inhibited at higher latitudes, where it is not as beneficial, and growth is induced in areas of higher predation. Specific goals are to determine if (1) a biogeographical cline in predation pressure corresponds to a gradient of symbiont frequency associating with the host, (2) symbiotic hosts have a higher fitness at low latitudes, and aposymbiotic hosts have a higher fitness at high latitudes, and (3) symbiont growth is promoted at low latitudes and inhibited at high latitudes. A combination of field and laboratory-based experiments will be conducted using ecological and molecular biology techniques. Bioactive compounds produced by symbionts of marine invertebrates can mediate multi-trophic interactions and potentially influence benthic community structure. There has been almost no research, however, on how ecological and environmental parameters influence the distribution of marine defensive endosymbionts.
Related Reference:
Linneman J, Paulus D, Lim-Fong G, Lopanik NB (2014) Latitudinal Variation of a Defensive Symbiosis in the Bugula neritina (Bryozoa) Sibling Species Complex. PLoS ONE 9(10): e108783. doi:10.1371/journal.pone.0108783
| Funding Source | Award |
|---|---|
| NSF Division of Ocean Sciences (NSF OCE) |