Identification and Characterization of miRNAs from Anole Lizard (Anolis carolinensis)

MicroRNAs represent a class of noncoding small RNAs of approximately 20nt length, which are evolutionarily conserved and play a vital role in various biological processes by either degrading or repressing mRNA translation. The Anole lizard (Anolis carolinensis) at genome sequence has been published recently, and Ensemble's automated BLAST reveals around 223 miRNAs. Independently, we performed an in silico comparative approach using all known sequences of animal pre-miRNAs as query sequence. Using our data and the automated hits from ensemble were downloaded in FASTA format and iteriated and validated for potential miRNAs, thus, we report 155 putative miRNAs from anole lizard. We determine the identity values of pre-miRNAs and mature miRNAs besides statistical sequence characteristics. Interestingly, those sequences which had identity less than 50% are also reported as they passed through the validation with high prediction confidence. Further, due to the fact that we used only animal miRNAs, and interestingly we found that two miRNAs (mir-414, mir-1171) from ensemble database had their query sequences from Arabidopsis thaliana and Chlamydomonas reinhardtii, which are very far phylogenetically related. Among 155 miRNAs nearly 52 miRNAs were homolog to chicken, followed by 39 from living fossil, platypus, an intermediate between birds and mammals. Further, we have reported the statistical sequence characteristics of pre and mature miRNA sequences. Most importantly, based on homology analysis of pre-miRNA, mature miRNA, miRNA families and clusters, we propose that miRNAs from anole lizard genome are closer to birds, than mammals. Therefore, our results add a new dimension to the studies related to the evolution of reptiles in general.