The evolution of genome and its relationship with social behavior in the honey bee

honey bee;behavior;evolution;adaptive introgression;genome

Fu, Chen

关键词: honey bee;    behavior;    evolution;    adaptive introgression;    genome;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/46682/Chen_Fu.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Social behavior in Honey bee has long attracted biologist's interest, especially its evolution. There are about 10 species in the genus Apis could be called "honey bee". Social behavior of these species differ in many aspects. Within the species Apis mellifera, there is also large variation in behavior among subspecies. Previous studies showed the behavior, together with morphological and physiological characters is strongly related with the environment the species (subspecies) distributed.Also, many effort has been made to elucidate the biogeography of Apis mellifera subspecies. In this way, honey bee, especially Apis mellifera, is a good system to study the evolution of behavior.In the same time, the mechanism of honey bee social behavior is complex and difficult to study. The genetic tools in honeybee is far less powerful than that of the model systems (e.g., Drosophila melanogaster). Also, social behavior is composed of many simpler components (endophenotype), and the mechanism of the social behavior can be understood until the mechanism of each of the simpler components is elucidated.In my dissertation study, I first studied the genetic mechanism for one of the endophenotypes of honey bee social behavior: circadian locomotion behavior. In 15 genes strongly correlated with the change of social behavior for individual bee (from hive working to foraging for the whole colony), 6 is correlated with either the circadian locomotion behavior or the response to light change or general locomotion strength.This work furthered our understanding of the relationship between the endophenotype (circadian locomotion) with social behavior in the mechanism level. This work in shown in chapter 2.Next, the genomic character that may "facilitate" the social behavior to be evolved in hymenoptera was approached. The high recombination rate and uneven gene distribution in low and high GC contentregions in the genome were two characters of hymenoptera genome. My work in this part (chapter 3) addressed how these genomic characters could be related with the evolution of honey bee social behavior. Previous researches concludedthat neural and behavioral related genes mainly distribute in the high GC content region and high recombination rate in the high GC region may speed up the evolution of these genes. The result from my work showed, however, that the evolution of the behavioral and neural related genes is faster than developmental genes even after the effect of GC content was controlled.This result indicate the effect of selection outraced the GC content in shaping the evolution of the genes related with honeybee social behavior. That if some genomic mechanism other than GC content may affect the evolution of social behavior in hymenoptera is yet to be understood.Also,my dissertation research made effort in elucidating the evolution of a few genomic regionsmay be associated with honey bee behavior.The biogeography of the species are often reflected in the gene evolution. Our results showed the repeated expansion of the honey bee subspecies into Europe left the sign of co-evolution in multiple regions containing genes associated with honey bee behavior. For European subspecies, unsurprisingly, we often found strong gene flow in these regions. This result indicates the gene flow might be an important mechanism for the co-evolution of these genomic regions and honey bee behavior. Chapter 4 described this part of work.Taken together, my dissertation work covered behavioral genetic, comparative genomic and population geneticapproaches to understand evolution of the honey bee social behavior and underlying genetic mechanisms.