Differences

This shows you the differences between two versions of the page.

--- 2020:groups:g3:start [2019/12/28 23:18] – menezes
+++ 2020:groups:g3:start [2024/01/09 18:45] (current) – external edit 127.0.0.1
@@ Line 2: / Line 2: @@
 **Group 3**
-<html><font size=6 face="Arial">Title</font></html>
+<html><font size=6 face="Arial">Microbial Matriarchy</font></html>
@@ Line 13: / Line 13: @@
 ===== Introduction =====
-{{:2020:groups:g3:wolb-4-1oqc6ga.png?300 |**Figure 1**}}
-//Wolbachia// are bacterias that infect a wide range of Arthoprods. This particular bacterial infection is maternally inherited and often result on bacterial manipulation of host reproduction dynamics. One of the main host reproduction manipulations of //Wolbachia// are Citoplasmatic Incompatibility (CI) and Male-killing (MK).
+{{:2020:groups:g3:screenshot_from_2020-01-08_17-19-21.png?300 |}}
-CI occurs when males infected with //Wolbachia// mate with females that are not infected. Such a cross results in aborted fertilization. By contrast, infected females can mate successfully with both infected and uninfected males (**Figure 1**).
+//Wolbachia// is a bacteria that infects a wide range of Arthropods. This particular bacterial infection is maternally inherited and often result in bacterial manipulation of host reproduction dynamics. One of the main host reproduction manipulations of //Wolbachia// is Male-killing (MK).
-MK //Wolbachia// kill a large proportion of a female’s male offspring. This phenotype is advantageous to the bacteria since surviving (and infected) daughters benefit from the death of their brothers through some form of fitness compensation (e.g. resource reallocation). These mechanisms give females infected with //Wolbachia// the upper hand, assisting the spread of //Wolbachia// into wild host population.
+MK //Wolbachia// leads to the mortality of all female’s male offspring in the fruitfly //Drosophila// //innubila//, resulting in an all-female cohort (**Figure 1**). Due to a high frequency of this mechanism in nature it was investigated the possible advantages MK could provide to host. In an experimental study, Unckless & Jaenike (2011) found that surviving (and infected) daughters benefit from the death of their brothers through some form of fitness compensation (e.g. resource reallocation) and that //Wolbachia// infection could increase fecundity in nutrient-deprived flies. These mechanisms are beneficial to //Wolbachia// since it ensures the vertical spread of infection.
-It is expected that the interplay of infected and healthy males and females can lead to different scenarios. In one extreme, //Wolbachia// succeeds and can even fixate permanently in an infected asexually-reproducing all-female population. In other scenarios, //Wolbachia// might become its own executioner, leading to the collapse of the whole system. Nevertheless, other intermediate scenarios encompass males and females, infected or not, coexisting in the population.
+It is expected that the interplay between infected and healthy females and healthy males can lead to different scenarios. In one extreme, MK //Wolbachia// becomes its own executioner, leading to the collapse of the whole system; in the other, //Wolbachia// infected and uninfected hosts can coexist. Nevertheless, the conditions leading to either system extinction or population coexistence are poorly understood.
 ===== Assignment =====
-Propose and analyze a mathematical model to investigate the effect of a trait responsible for the proportion of offspring that is born infected with //Wolbachia//, as well as the effect of a trait related to male offspring mortality on invasiveness and dominance of //Wolbachia// infected host population.
+Propose and analyze a mathematical model to elucidate this dynamics.
-===== Questions & Suggestions =====
+===== Suggested questions =====
+  * Investigate the system's response to varying degrees of maternal inheritance of MK //Wolbachia// infection. How can infected host population establish and dominate?
-  * Investigate the system response to varying degrees of maternal inheritance of //Wolbachia// infection. How can infected host population establish and dominate?
+  * It has been proposed that //Wolbachia// infections can lead to an increase in fecundity. According to your model, in which situations does infected and uninfected females coexist?
-  * It has been proposed that //Wolbachia// infections can lead to the extinction of the male population (leading to the collapse of the whole system in some cases) [Merçot and Poinsot, 2009]. According to your model, in which situations does this collapse occur and how it can be avoided ?
+  * Under which circumstances MK //Wolbachia// infection can lead to system collapse?
-  * Considering a system composed only by infected males and females, can the healthy host phenotype invade the population? Is there a possibility of lasting coexistence of infected and uninfected individuals in the host population?
-**BONUS**: consider a trade-off between maternal inheritance and offspring population size of infected hosts and explore parameter the regions in which //Wolbachia// can invade the population.
+Further well-grounded questions from the group are welcome.
 ===== References =====
-  * Merçot, Hervé, and Denis Poinsot. "Infection by Wolbachia: from passengers to residents." Comptes rendus biologies 332, no. 2-3 (2009): 284-297.
+  * Unckless, R. L., & Jaenike, J. (2011). Maintenance of a male-killing //Wolbachia// in //Drosophila innubila// by male-killing dependent and male-killing independent mechanisms. Evolution, 66(3), 678–689. doi:10.1111/j.1558-5646.2011.01485.x [[https://onlinelibrary.wiley.com/doi/full/10.1111/j.1558-5646.2011.01485.x]]
+  * Sullivan, J., & Jaenike, J. (2006). Male-killing Wolbachia and male mate choice: a test with Drosophila innubila. Evolutionary Ecology Research, 8(1), 91-102. [[http://www.evolutionary-ecology.com/abstracts/v08/1968.html]]