Complete Mitochondrial Genome of Three Species of the Genus Microtus (Arvicolinae, Rodentia)

Abstract

The 65 species of the genus Microtus have unusual sex-related genetic features and a high rate of karyotype variation. However, only nine complete mitogenomes for these species are currently available. We describe the complete mitogenome sequences of three Microtus, which vary in length from 16,295 bp to 16,331 bp, contain 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 transfer RNA genes and a control region. The length of the 13 PCGs and the coded proteins is the same in all three species, and the start and stop codons are conserved. The non-coding regions include the L-strand origin of replication, with the same sequence of 35 bp, and the control region, which varies between 896 bp and 930 bp in length. The control region includes three domains (Domains I, II and III) with extended termination-associated sequences (ETAS-1 and ETAS-2) in Domain I. Domain II and Domain III include five (CSB-B, C, D, E and F) and three (CSB-1, CSB-2, and CSB-3) conserved sequence blocks, respectively. Phylogenetic reconstructions using the mitochondrial genomes of all the available Microtus species and one representative species from another genus of the Arvicolinae subfamily reproduced the established phylogenetic relationships for all the Arvicolinae genera that were analyzed.

The Complete Mitochondrial Genome of a Neglected Breed, the Peruvian Creole Cattle (Bos taurus), and Its Phylogenetic Analysis

“…In addition, gene order and structure were similar to previously reported B. taurus mitogenomes [23,24]. The AT and GC contents were 60.07% and 39.93%, respectively, revealing a nucleotide composition bias of the PCC mitogenome towards adenine and thymine, which is commonly observed in other mammals [20,25,26].…”

“…Non-coding regions are known to possess controlling elements for transcription and replication [37] and include intergenic spacers, L-strand origin of replication, and control region [38]. The organization of the origin of replication of the PCC mitogenome is similar to that of other mammal species [26,39,40]. Similar to previous work on other Bos mitogenomes [20,21], the length of the control region of the PCC mitochondrial genomes was 910 bp.…”

“…Indices of codon usage bias show differences in the occurrence of codon usage, indicating genomic evolutionary patterns [27]. Start (ATG) and stop (TAA) codons were the most abundant in the PCC mitogenome, which is in agreement with the mitochondrial genome of other mammals [26,28,29]. Incomplete stop codon presence is commonly found in mitogenomes of other vertebrates [30][31][32], which might be further completed by the posttranscriptional poly-adenylation of the 3 end of the mRNA [33,34].…”

The Complete Mitochondrial Genome of a Neglected Breed, the Peruvian Creole Cattle (<em>Bos taurus</em>), and Its Phylogenetic Analysis

“…In addition, gene order and structure were similar to previously reported B. taurus mitogenomes [35,36]. The AT and GC content was 60.07% and 39.93%, respectively, revealing a nucleotide composition bias of the PCC mitogenome towards adenine and thymine, which is commonly observed in other mammals [32,37,38].…”

Characterisation of the Complete Mitochondrial Genome of Critically Endangered Mustela lutreola (Carnivora: Mustelidae) and Its Phylogenetic and Conservation Implications

“…The overall sequence length of known mustelid mitogenomes, excluding the control region, is nearly identical, as most variations in their size are due to differences in the D-loop and associated promoters sequence length [ 40 , 53 , 61 ]. Analysis of intergenic spacers and overlapping regions in the M. lutreola mitogenome indicated its compactness greater than in Microtus sp., Vulpes vulpes and N. vison , and less than in Lepus yarkandensis and Lutra lutra [ 36 , 57 , 62 , 63 , 64 ]. In general, the European mink mitogenome fits in well with the pattern observed in animals, according to which mtDNA is characterised as a highly genetically economised genome with intronless genes and only short sections of non-coding DNA and intergenic spacers [ 65 , 66 ].…”