Meeting Abstract

49.5  Monday, Jan. 5  MicroRNAs from cichlid genomes LOH, Y.-H.E.**; STREELMAN, J.T.; Georgia Institute of Technology; Georgia Institute of Technology yloh3@gatech.edu

MicroRNAs are small RNA molecules of approximately 22 nucleotides known to hybridize to 3′ untranslated regions (3′ UTRs) of target messenger RNAs (mRNAs), thereby effecting gene silencing through translation inhibition or targeted mRNA degradation. They are an integral class of regulatory molecules, with each microRNA having the potential to regulate many genes (200 on average), while each gene may in turn be regulated by numerous different microRNAs. While microRNA regulation has been implicated in a diverse range of biological processes and diseases, such as development, cell proliferation and differentiation, neurogeneration and neurodegeneration, and many forms of cancer, the complex interplay between microRNAs and their target genes also provides fertile grounds on which regulatory mutations might produce phenotypic differentiation without adverse pleiotropic consequences. Cichlid fishes from the East African Rift lakes Victoria, Tanganyika and Malawi display a compendium of diverse and replicated morphological and behavioral phenotypes, with almost 2000 unique species having evolved over a period of just 10 million years. Has the evolution of diversity in cichlids been driven by genetic changes in microRNAs or their target sequences? We used computational methods to predict microRNAs from a growing collection of cichlid genomic resources. We also identified thousands of corresponding putative target sequences in 3′ UTRs of cichlid genes. We aim to integrate variation in microRNA and/or target sequences with differential expression of microRNAs and their target genes to explore the role of these molecules in rapid phenotypic diversification.