Mitochondrial control region and protein coding genes sequence variation among phenotypic forms of brown troutSalmo truttafrom northern Italy

1994 ◽  
Vol 3 (2) ◽  
pp. 161-171 ◽  
Author(s):  
E. GIUFFRA ◽  
L. BERNATCHEZ ◽  
R. GUYOMARD
2013 ◽  
Vol 103 (5) ◽  
pp. 479-487 ◽  
Author(s):  
Efrén Remesal ◽  
Blanca B. Landa ◽  
María del Mar Jiménez-Gasco ◽  
Juan A. Navas-Cortés

Populations of Sclerotium rolfsii, the causal organism of Sclerotium root-rot on a wide range of hosts, can be placed into mycelial compatibility groups (MCGs). In this study, we evaluated three different molecular approaches to unequivocally identify each of 12 previously identified MCGs. These included restriction fragment length polymorphism (RFLP) patterns of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (rDNA) and sequence analysis of two protein-coding genes: translation elongation factor 1α (EF1α) and RNA polymerase II subunit two (RPB2). A collection of 238 single-sclerotial isolates representing 12 MCGs of S. rolfsii were obtained from diseased sugar beet plants from Chile, Italy, Portugal, and Spain. ITS-RFLP analysis using four restriction enzymes (AluI, HpaII, RsaI, and MboI) displayed a low degree of variability among MCGs. Only three different restriction profiles were identified among S. rolfsii isolates, with no correlation to MCG or to geographic origin. Based on nucleotide polymorphisms, the RPB2 gene was more variable among MCGs compared with the EF1α gene. Thus, 10 of 12 MCGs could be characterized utilizing the RPB2 region only, while the EF1α region resolved 7 MCGs. However, the analysis of combined partial sequences of EF1α and RPB2 genes allowed discrimination among each of the 12 MCGs. All isolates belonging to the same MCG showed identical nucleotide sequences that differed by at least in one nucleotide from a different MCG. The consistency of our results to identify the MCG of a given S. rolfsii isolate using the combined sequences of EF1α and RPB2 genes was confirmed using blind trials. Our study demonstrates that sequence variation in the protein-coding genes EF1α and RPB2 may be exploited as a diagnostic tool for MCG typing in S. rolfsii as well as to identify previously undescribed MCGs.


Genome ◽  
2009 ◽  
Vol 52 (12) ◽  
pp. 975-984 ◽  
Author(s):  
Xiaoyu Kong ◽  
Xiaoli Dong ◽  
Yanchun Zhang ◽  
Wei Shi ◽  
Zhongming Wang ◽  
...  

The organization of fish mitochondrial genomes (mitogenomes) is quite conserved, usually with the heavy strand encoding 12 of 13 protein-coding genes and 14 of 22 tRNA genes, and the light strand encoding ND6 and the remaining 8 tRNA genes. Currently, there are only a few reports on gene reorganization of fish mitogenomes, with only two types of rearrangements (shuffling and translocation) observed. No gene inversion has been detected in approximately 420 complete fish mitogenomes available so far. Here we report a novel rearrangement in the mitogenome of Cynoglossus semilaevis (Cynoglossinae, Cynoglossidae, Pleuronectiformes). The genome is 16 371 bp in length and contains 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and 2 main noncoding regions, the putative control region and the light-strand replication origin. A striking finding of this study is that the tRNAGln gene is translocated from the light to the heavy strand (Q inversion). This is accompanied by shuffling of the tRNAIle gene and long-range translocation of the putative control region downstream to a site between ND1 and the tRNAGln gene. The remaining gene order is identical to that of typical fish mitogenomes. Additionally, unique characters of this mitogenome, including a high A+T content and length variations of 8 protein-coding genes, were found through comparison of the mitogenome sequence with those from other flatfishes. All the features detected and their relationships with the rearrangements, as well as a possible rearrangement pathway, are discussed. These data provide interesting information for better understanding the molecular mechanisms of gene reorganization in fish mitogenomes.


Genome ◽  
2004 ◽  
Vol 47 (3) ◽  
pp. 535-545 ◽  
Author(s):  
Sergio L Pereira ◽  
Erwin T Grau ◽  
Anita Wajntal

The control region (CR) plays an important role in replication and transcription in the mitochondrial genome. Its supposedly high rate of DNA substitution makes it a suitable marker for studies of population and closely related species. Three domains can be identified in CR, each having its own characteristics regarding base composition, pattern of variability and rate of DNA substitution. We sequenced the complete CR for 27 cracids, including all 11 genera to characterize its molecular organization, describe patterns of DNA substitution along the gene, and estimate absolute rates of DNA substitution. Our results show that cracid CR organization and patterns of DNA substitution are typical of other birds. Conserved blocks C and B, fused CSB2/3, and a putative segment for bidirectional replication not usually present in birds were identified in cracids. We also suggest a new delimitation for domains to allow better comparisons among CRs at different taxonomic ranking. Our estimates of absolute rates of DNA substitution show that, in general, CR evolves at a rate slower than that of two protein-coding genes (CR, 0.14%–0.3%; ND2, 0.37%–0.47%; and cytochrome b, 0.29%–0.35% per site per million years within genera). Within CR domains, rates within genera ranged from 0.05% to 0.8% per site per million years.Key words: mitochondrial control region, molecular evolution, Cracidae, Aves.


2019 ◽  
Author(s):  
Gang Liu ◽  
Lizhi Zhou ◽  
Guanghong Zhao

The phylogenetic relationships between owls and nightjars are rather complex and controversial. To clarify these relationships, we determined the complete mitochondrial genomes of Glaucidium cuculoides, Otus scops, Glaucidium brodiei, Caprimulgus indicus, and Strix leptogrammica, and estimated phylogenetic trees based on the complete mitochondrial genomes and aligned sequences from closely related species that were obtained in GenBank. The complete mitochondrial genomes were 17392, 17317, 17549, 17536, and 16307 bp in length. All mitochondrial genomes contained 13 protein-coding genes, two rRNAs, 22 tRNAs, and a putative control region. All mitochondrial genomes except for that of Strix leptogrammica contained a pseudo-control region. ATG, GTG, and ATA are generally start codons, whereas TAA is the most frequent stop codon. All tRNAs in the new mtDNAs could be folded into canonical cloverleaf secondary structures except for tRNASer (AGY) and tRNALeu (CUN) , which missing the “DHU” arm. The phylogenetic relationships demonstrated that Strigiformes and Caprimulgiformes are independent orders, and Aegothelidae is a family within Caprimulgiformes. The results also revealed that Accipitriformes is an independent order, and Pandionidae and Sagittariidae are independent families. The results also supported that Apodiformes is polyphyletic, and hummingbirds (family Trochilidae) belong to Apodiformes. Piciformes was most distantly related to all other analyzed orders.


Sign in / Sign up

Export Citation Format

Share Document