Remiz Research Articles

Sequencing and analysis of the complete mitochondrial genome of Remiz consobrinus

The complete mitochondrial genome sequence of Remiz consobrinus was determined using long PCR and conserved primers walking approaches. Based on the results of assembling and annotation, the structure, sequence composition and codon usage of the genome protein-coding genes were analyzed, and the prediction of the secondary structure of 22 tRNA and 2 rRNA, the control region structure, and the phylogeny were also conducted, which provided new information for phylogenetic studies of passerine birds. The entire mitochondrial genome of Remiz consobrinus was 16 737 bp in length, the accession number was KC463856 and the content of A, T, C, and G were 27.8%, 21.5%, 35.4%, and 15.3%, respectively. The genome harbored the same gene order with that of other birds, and contained 13 protein coding genes (PCGs), 22 tRNA, 2 rRNA, and a non-coding control region. There were 77 bp intergenic intervals between 18 pair genes and 30 bp overlaps between 7 pair genes. Except for ND3 gene, which used ATT as the initiation codon, all other PCGs started with the typical ATG codon. Except for COIII and ND4, which used incomplete termination codon T, the other 11 PCGs used standard TAA, TAG, AGA or AGG as termination codons. The tRNAs all formed typical cloverleaf secondary structure, except for tRNASer-AGN, which lost the DHU arm in its structure. A total of 27 base mismatches appeared, with 19 common G-U mismatches. The predicted secondary structure of SrRNA and LrRNA contained 3 domains with 47 helices and 6 domains with 60 helices, respectively. Besides F-box, D-box, C-box, and B-box, Bird similarity-box and CSB1-box were also found in the control region of Remiz consobrinus, as found in other bird species. Our results suggest Remizidae as a separate family. The monophyly of Sylviidae and Remizidae was supported.