Suegene Noh, Assistant Professor of Biology at Colby College, began her presentation on genomes shaped by evolution by looking at the social amoeba Dictyostelium dicoideum. In the case of the \u201cdicty\u201d, as she referred to them, amoebas are unicellular organisms, but they have the ability to aggregate and form mounds. In this process the dicty form a fruiting body with spores and a stalk in order survive harsh conditions, and in this form, they are able to eat bacteria. Organisms that have singular and multicellular stages have facultative multicellularity as it benefits the singular organism to band together with others of its kind for survival. However, when genetically different cells make up the same body their interests tend to be different. Human cells do not behave in this way because they are identical, but they do conflict in other ways such as cancerous cells, which have a very different agenda from normally developed cells. Professor Noh describe fruiting bodies with multiple different types of dicty as chimeric and she used those in her own research.<\/p>\n
In her lab she has compared the ways in which chimeric dicty genes are expressed compared to those of clonal genes (fruiting bodies made up of one strain of dicty). In her research she used Illumina Cell machine to sequence the whole genome of the dicty mounds. She used four pairs of wild dicty strains and out of those made two clonal samples and one chimeric sample and repeated the study four times. She found that in the chimeric samples, sometimes they would produce less or more of certain genes compared to the clonal samples, and more frequently genes were biased down in chimeras. However, the few up regulated genes in the chimeric samples were involved in the development of the fruiting body and the cAMP response which is important for the aggregation of the Dicty. These changes in gene expression demonstrate that the chimeric genes selected for those that would help the fruiting body survive the best. This shows that the process of going through this cycle means that the chimeric samples will be more \u201cfit\u201d than the clonal samples.<\/p>\n
Professor Noh used a second example to demonstrate the effects of social conflict on the evolution of the dicty. She discussed three types of microbes that infect the dicty and keep them from forming the fruiting bodies that allow them to survive. Each of the three types of bacteria interact with the host in a different way, but the dicty have evolved in different ways due to the social conflict that they have endured with either agricolaris, bonniea, or hayleyella. Some of the audience members asked why professor Noh chose to get the strains of dicty that she used from the wild. She explained to the roome that some of the dicty strains that are grown in the labs have been effected by the environment in which they were made, and by choosing to select strains from the wild she was able to improve upon the validity of her own research.<\/p>\n","protected":false},"excerpt":{"rendered":"
Suegene Noh, Assistant Professor of Biology at Colby College, began her presentation on genomes shaped by evolution by looking at the social amoeba Dictyostelium dicoideum. In the case of the \u201cdicty\u201d, as she referred to them, amoebas are unicellular organisms, but they have the ability to aggregate and form mounds. In this process the dicty … <\/p>\n