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Tribes and genera

Tribe: Alberproseniini (genus Alberprosenia)

The two similar species of Alberprosenia forming this tribe are unusually small Triatominae (adults up to 5 mm in length) with unusually short heads, which have been little studied beyond their original descriptions. They have no known epidemiological significance. The tribal, generic, and species concepts are entirely morphologi- cal,7 although A. goyovargasi has been reared in the laboratory by feeding on human blood42 which supports inclusion in the Triatominae (“Torrealbaia martinezi” previously ascribed to this tribe43 has been shown to be a Harpactorinae24).

Table 6.4 Mitochondrial molecular markers most commonly used in systematics

Markers frequently used in molecular systematics

Markers

Strengths

Weaknesses

mtDNA Mitochondrial DNA; complete genome is 17,015 bp

Evolves faster than nuclear genome; clonally inherited (maternal lineage); useful for studies of closely related taxa that have diverged recently; amplification and sequencing is easier than for nuclear rDNA genes

The high substitution rate can be disadvantageous for resolving divergences of more than 5—10 Mya; saturation is a major cause of homoplasy and erases phylogenetic signal

12S Gene 12S

srRNA = mitochondrial small ribosomal subunit (mt-srRNA); total length 781 bp; region analyzed is usually 339—371 bp

Shows the lowest

evolutionary rate within mtDNA markers; useful up to the level of species within the same genus; can reveal differences at population level

Tends to become saturated at higher taxonomic levels; its use for comparison of species of different genera and tribes does not appear to be recommendable

16S Gene 16S

rRNA = mitochondrial large ribosomal subunit (mtlrRNA); total length 1270 bp; region analyzed are usually fragments of 284 bp and from 501—510 bp

Appears to evolve in parallel with 12S, but is more variable, and so tends to reveal greater differences between species of different tribes

Differences between species of different genera can appear similar to those within the same genus; its usefulness for analyses at genus or higher levels does not appear to be recommendable

COI Cytochrome c oxidase subunit 1; total length 1534 bp; regions analyzed are fragments of 1431 —1447 bp and fragments of 636—661 bp

Evolves slightly faster than NAD1 but slower than Cyt b at low level comparisons; useful for studies of closely related species; used for barcoding of various organisms

Saturation becomes a

problem in comparison of distant species and at higher taxonomic levels.36 Not applicable for identifying some Southern American Triatoma species which may have diverged recently23

NAD1 NADH

dehydrogenase subunit 1; total length 912—933 bp; region analyzed is usually the complete gene

Evolves faster than ITS-2 at low level comparisons; useful for studies of closely related species

Saturation is already

occurring when comparing distant species of the same genus

Cyt B Cytochrome B total length 1132 bp; several different fragments are analyzed, from 313 to 682 bp

This is the fastest evolving mtDNA gene; useful for comparison of subspecies (intrapopulational, interpopulational, between morphs, and between subspecies)

Saturation may become a problem in analysis of distant species and higher taxa

Table 6.4 (Continued)

Markers frequently used in molecular systematics

Markers

Strengths

Weaknesses

NAD4NADH

dehydrogenase subunit 4; total length 1331 bp; region analyzed are usually fragments of 401-631 bp

Useful for studies of closely related species and for population genetics analyses. Similar level of resolution than Cyt b. Is one of the most variable protein-coding genes in insects in general

Low level of variation and not useful information for phylogenetic inferences in T. infestans

NAD5NADH

dehydrogenase subunit 5; total length 1712 bp; region analyzed is complete gen

Is one of the most variable protein-coding genes in insects in general. Useful for population genetic studies

Low level of variation in T. infestans. Little known in other Triatominae. Only a portion of the ND5 gene, should be useful for phylogeographic studies

COII Cytochrome c oxidase subunit 2; total length 679 bp; regions analyzed are fragments of 220- 364 bp and fragments of 576-649 bp

Available for many

Triatomini and Rhodniini genera and species. Provides congruent phylogenies in combined analyses with other mtDNA markers

Saturation can be considered in analysis of distant species and higher taxa

Bp, base pairs; Mya, million years ago. Gene and fragment lengths refer to published studies on Triatominae.

Source: Adapted from Justi SA, Dale C, Galvao C. DNA barcoding does not separate South American Triatoma (Hemiptera: Reduviidae), Chagas disease vectors. Parasit Vectors 2014;7:51923; Bargues MD, Zuriaga MA, Mas-Coma S. Nuclear rDNA pseudogenes in Chagas disease vectors: evolutionary implications of a new 5.8S 1ITS2 paralogous sequence marker in triatomines of North, Central and northern South America. Infect Genet Evol 2014;21:134-5634; Zuriaga MA, Mas-Coma S, Bargues MD. A nuclear ribosomal DNA pseudogene in triatomines opens a new research field of fundamental and applied implications in Chagas disease. Mem Inst Oswaldo Cruz 2015;110:353-6235; Mas-Coma S, Bargues M. Populations, hybrids and the systematic concepts of species and subspecies in Chagas disease triatomine vectors inferred from nuclear ribosomal and mitochondrial DNA. Acta Trop 2009;110:112-3636; Monteiro FA, Peretolchina T, Lazoski C, Harris K, Dotson EM, Abad-Franch F, et al. Phylogeographic pattern and extensive mitochondrial dna divergence disclose a species complex within the Chagas disease vector Triatoma dimidiata. PLoS ONE 2013;8:e7097437; Gomez-Palacio A, Triana O, Jaramillo-O N, Dotson EM, Marcet PL. Eco-geographical differentiation among Colombian populations of the Chagas disease vector Triatoma dimidiata (Hemiptera: Reduviidae). Infect Genet Evol 2013;20:352-6138; Gomez-Palacio A, Triana O. Molecular evidence of demographic expansion of the Chagas disease vector Triatoma dimidiata (Hemiptera, Reduviidae, Triatominae) in Colombia. PLoS Negl Trop Dis 2014;8:e273439; Fernandez CJ, Perez de Rosas AR, Garcia BA. Variation in mitochondrial NADH dehydrogenase subunit 5 and NADH dehydrogenase subunit 4 genes in the Chagas disease vector Triatoma infestans (Hemiptera: Reduviidae). Am J Trop Med Hyg 2013;88:893-9640; Diaz S, Panzera F, Jaramillo-O N, Perez R, Fernandez R, Vallejo G, et al. Genetic, cytogenetic and morphological trends in the evolution of the Rhodnius (Triatominae: Rhodniini) trans-andean group. PLoS ONE 2014;9:e87493.41

 
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