Amal Bajaffer, a Ph.D. candidate under the supervision of ProfessorTakashi Gojobori defended her Ph.D. thesis "Comparative Study of Memory Associated Genes and
Lactate Mediated Neural Plasticity genes".
is one of the highest cognitive functions that differentiates higher organisms
from others because of its fundamental function to all learning and studying
process. Recently, it was suggested that lactate works as a signaling molecule
in neuronal plasticity system in long-term memory (LTM). These functions are
reported only at mice so far, but it would be a universal phenomenon among
various higher organisms. Because lactate is organic acid that is involved with
energy production, it is of particular interest to know how memory associated
genes including a lactate-mediated neural plasticity (LMNP) genes get involved
during evolution. I here set the purpose of my studies as to understand the
evolutionary origin and process of these memory-associated genes. Conducting an
extensive literature survey, I collected a total of 302 genes of mice as memory
associated genes. I, then, compared the number of genes orthologous to the 302
mice memory-associated genes among 11 representative organisms that I have chosen
for the present study. As a result, I found that these memory-associated genes
emerged at different time points during evolution, even before the emergence
time of the organisms where memory function was reported. It suggests that
memory function could be evolutionarily established gradually but not at once.
Moreover, I examined 386 of LMNP-related genes of mice and other organisms to
understand the evolutionary origin and processes of those genes that were
identified by RNA-seq analyses (Margineanu et al., 2018). I found that the
emergence times of LMNP genes were varied with genes, suggesting that the LMNP
system may have been also formed gradually until its completion of the system
around at the time of the common ancestor of vertebrates. From those studies, I
conclude that the memory system and LMNP system has been formed by gradual
participation of newly emerging genes during evolution.
Bajaffer is a Ph.D. candidate in Taskashi Gojobori's group at King Abdullah
University of Science and Technology (KAUST) thuwal, Saudi Arabia. She is a
Master of Science in Biology, University of Texas at San Antonio, 2014, and
Bachelor of Science in Biology-Microbiology, King Abdul-Aziz University, 2008.
Her research interests broadly concerns Glycogenolysis, Long-term memory,
long term potentiation, Astrocyte-neuron interaction, immediate early genes.